Development and Validation of the Self-efficacy Questionnaire in multiple sclerosis patients

OBJECTIVE

Self-efficacy is one of the factors affecting on the quality of life and adjustment to the chronic diseases such as multiple sclerosis. Self-efficacy is the individual's belief that they have the ability to overcome challenges presented to them. The current study aimed to develop and validate of selfefficacy questionnaire in Iranian MS patients.

MATERIALS AND METHODS

This is a methodological study that was performed in three phases. In the first phase, the concept of self-efficacy was defined through qualitative content analysis approach. In the second phase, early items of questionnaire was generated according to findings of the first phase. In the final phase, validation of the developed questionnaire were evaluated using face, content and construct validity as well as reliability.

RESULTS

In exploratory factor analysis, four subscales including: adherence to medication regimens (5 items), social performance control (4 items), symptom management (4 items) and maintain independence and activity (5 items) were extracted by Eigen value above one and factor load above 0.3. Internal consistency and stability of the developed questionnaire confirmed with 0.91 and 0.88 respectively that indicated acceptable reliability.

CONCLUSIONS

The 18-item developed questionnaire is valid and reliable for measurement of self-efficacy of Iranian MS patients.

Development of a method using QuEChERS and LC-MS/MS for analysis of per- and polyfluoroalkyl substances in rice matrix

Detection of per- and polyfluoroalkyl substances (PFAS) in food is crucial for ensuring food safety. Therefore, we combined a quick, easy, cheap, rugged, and safe (QuEChERS) extraction method with liquid chromatography-triple-quadrupole mass spectrometry (LC-MS/MS) to detect 35 PFAS in rice. The solvents (water and acetonitrile) were adjusted to pH 2.4, a mixture of anhydrous MgSO4, NaCl, and NaOAc was used for extraction, and anhydrous MgSO4, a primary/secondary amine, and graphitized carbon black were applied for purification. The limits of detection and recovery were 0.005-0.100 ng·g-1 and 86.5 %-126.4 %, respectively. When this method was used to detect PFAS in packaged instant rice cooked in a microwave or boiled in water, the microwaved sample showed a lower PFAS content. However, both samples had PFAS contents within WHO guidelines and were safe for consumption. This method can be extended to detect PFAS levels in other foods exposed to packaging materials containing PFAS.

Impurity assessment, development and validation of an RP-HPLC method for the determination of eleven potential impurities of eltrombopag precursor

Eltrombopag is an oral non-peptide thrombopoietin receptor (TPO-R) agonist indicated for the treatment of thrombocytopenia in patients with persistent or chronic immune thrombocytopenia (idiopathic thrombocytopenic purpura, ITP) or chronic hepatitis C infection and the treatment of severe aplastic anemia. The purpose of this research was to assess the possible impurities that may carry over to eltrombopag from its precursor Eltro-1 (3'-amino-2'-hydroxy-[1,1'-biphenyl]-3-carboxylic acid) and to develop a specific analytical method for the determination of these impurities. Eltro-1 samples synthesized by two different synthesis routes were investigated during the evaluation and method development studies. Besides the expected process-related impurities (Eltro-1A - Eltro-1J), e.g., starting materials, intermediates, and/or compounds formed from their further reactions, an unknown impurity detected above 0.10% was identified by LC-MS, synthesized and fully characterized by NMR, MS and FTIR (Eltro-1K). Accordingly, an HPLC-RP method for the determination of eleven impurities (Eltro-1A - Eltro-1K) in Eltro-1 was developed and validated according to ICH Q2. The control limits for impurities in Eltro-1 were set at ≤ 0.15% for Eltro-1A - Eltro-1J and ≤ 1.0% for Eltro-1K based on fate, spike-purge and carryover studies and in accordance with the ICH M7 classification for impurities in drug substance. Eltro-1 and eleven impurities at the specification limit were separated from each other and the diluent peaks with sufficient resolution without interference. Separation was performed on a Waters XBridge C18 column (150 × 4.6 mm, 3.5 μm) at 40 °C with a 10 µL injection volume at a detection wavelength of 220 nm and 15 °C sample temperature. The gradient elution is performed at a flow rate of 1.0 mL/min for 40 min with mobile phase A (0.1% orthophosphoric acid in water) and B (acetonitrile) according to the following program: Time (min) / Acetonitrile (%): 0/0, 35/70, 36/0, 40/0. Test and standard solutions were prepared at a concentration of 1.0 mg/mL and 1.0 µg/mL, respectively, using a mixture of mobile phase A and acetonitrile (75/25) as diluent. This is the first specific, selective, sensitive, linear, precise, accurate, and robust HPLC method for the determination of Eltro-1A - Eltro-1K in Eltro-1, which showed no significant degradation under thermal stress, photostability (UV and VIS), and standard accelerated and long-term stability conditions.

Translation and validation of prolonged grief disorder (PG-13) scale in Urdu among bereaved adolescents with intellectual disability

BACKGROUND

The study aimed to translate and validate the Prolonged Grief Disorder (PG-13) scale from English into Urdu language. This involved examining its psychometric properties, evaluating its factor structure and assessing both convergent and discriminant validity. The study was conducted within the cultural context of Pakistan and focused on the assessment of manifestations of grief, including symptoms of prolonged grief, in adolescents with mild-to-moderate intellectual disability (ID). The PG-13 scale was selected for this study due to its demonstrated accuracy in measuring prolonged grieving symptoms in bereaved population.

METHOD

A total of 140 adolescents, aged 10-19 years according to the World Health Organization (WHO) 2018 criteria, were selected from 14 cities in Pakistan. These participants had lost loved ones within the time span of the last 4 years. The WHO (2018) guidelines for translation, adaptation, and validation were followed.

RESULTS

The findings suggest that the translated and validated PG-13 scale has adequate psychometric properties, with Cronbach alpha coefficient of .97. Confirmatory factor analysis supports a single-factor structure for the scale, with factor loadings ranging from .80 to .95.

CONCLUSION

The PG-13 Urdu version is a reliable and validated scale available for assessing grieving symptoms in the Pakistani context.

The development and validation of the One Health Community Assessment

Interdisciplinary collaborations to address human, animal, and environmental health have been emphasized since the inception of the One Health framework. A quantitative survey instrument was developed to measure perceptions of the impacts of pets on One Health. Using the exploratory sequential mixed methods approach, 20 interviews were conducted with individuals from a racially diverse and low-socioeconomic status community in the U.S. to understand their perceptions of One Health. Data from those interviews informed the development of a Likert scale survey measuring individual perceptions of community, human, pet, and environmental health and welfare, as well as the connections between the domains of the One Health triad (human, animal, and environment). The resulting One Health Community Assessment (OHCA) was administered in two urban and two rural underserved U.S. communities longitudinally (2018-2021) through door-to-door data collection as well as phone, email, and text surveys. Validation of the instrument was completed using data collected in the third and fourth years of the study (n = 654). Factor analysis with orthogonal varimax rotation was used to assess the structure and internal consistency of the OHCA. Five subscales explained 42.4% of the variance in our 92-item instrument: community health (Cronbach's α = 0.897), human health (α = 0.842), pet health (α = 0.899), environmental health (α = 0.789), and connections between domains of One Health (α = 0.762). The OHCA represents the first reliable and validated instrument to measure the impacts of pets on One Health.

A specific chiral HPLC method for lifitegrast and determination of enantiomeric impurity in drug substance, ophthalmic product and stressed samples

Lifitegrast is a lymphocyte function-associated antigen-1 (LFA-1) antagonist used to treat the indications and symptoms associated with dry eye disease (DED), one of the most common ocular surface diseases. Lifitegrast has a chiral center, and the S-enantiomer (S-Lif) is responsible for the therapeutic effects, while the R-enantiomer (R-Lif) lacks efficacy in the treatment of DED. Lifitegrast ophthalmic solution containing 5% lifitegrast was approved by the United States Food and Drug Administration (FDA) in July 2016 for the treatment of DED in patients 17 years of age and older. The objective of this study was to develop a chiral HPLC method for the determination of the enantiomeric impurity of lifitegrast in the drug substance and in the ophthalmic product. In addition, we aimed to investigate the effect of stress and stability conditions on the enantiomeric purity of lifitegrast in both drug substance and ophthalmic solution. During the method development studies, four known lifitegrast impurities (Lif. Imp. A-D) and stressed lifitegrast samples were injected to ensure the specificity of the developed method. The enantiomers of lifitegrast are well separated with a resolution of higher than 4.0. They are also well separated from the peaks of the diluent, impurities, and the placebo used to prepare the ophthalmic solution without interference in 20 min. Chiral separation was achieved using a Chiralpak AD-H column (250 × 4.6 mm, 5.0 μm) at 40 °C with a mobile phase consisting of a mixture of n-hexane, 2-propanol, and formic acid (500:500:2, v/v/v) at a flow rate of 1.0 mL/min and a detection wavelength of 260 nm. Methanol was used as the diluent, and the drug substance solution was found to be stable for 48 h at 15 °C. The optimized chiral HPLC method for lifitegrast was validated according to ICH Q2, and the calibration curves showed excellent linearity for R-Lif (0.0369 - 1.816 µg/mL). This is the first stability-indicating, specific / selective, sensitive, linear, precise, accurate, and robust chiral HPLC method for the determination of R-Lif in S-Lif. The amount of enantiomeric impurity R-Lif in S-Lif increased under all stress and photostability test conditions without exceeding the acceptable impurity limit, with the most significant increase observed at elevated temperatures (105 °C) for both the drug substance in powder form and the ophthalmic drug solution.

Development of an effective cleaning technique and ancillary analytical method for estimation of residues of selected kinase inhibitors from stainless steel and glass surfaces by swab sampling

Importance of cleaning validation in the pharmaceutical industry cannot be overstated. It is essential for preventing cross-contamination, ensuring product quality & safety, and upholding regulatory standards. The present study involved development of an effective cleaning method for five selected kinase inhibitors binimetinib (BMT), selumetinib (SMT), brigatinib (BGT), capmatinib (CPT), and baricitinib (BRT). For checking the effectiveness of the developed cleaning technique, a sensitive and specific RP-HPLC based analytical method employing a diode array detector has been established to quantitate drug residue on glass and stainless steel surfaces. A reproducible swab sampling protocol utilizing TX714A Alpha swabs wetted with an extracting solvent has been developed to collect representative samples from both surfaces. Chromatographic separation of selected kinase inhibitors was achieved in gradient mode using an Agilent Zorbax eclipsed C18 column with acetonitrile and 10 mM ammonium formate as the mobile phase. The analytes were chromatographically separated in a 12 min run time. The mean swab recovery for each drug from glass and stainless steel surfaces exceeded 90%. Cleaning with IPA (70%) and acetone (70%) effectively removed residues for all five drugs. A solution comprising 10 mM SDS with 20% IPA demonstrated good efficacy in cleaning residues of BGT, BRT, and CPT, but exhibited lower efficacy for SMT and BMT.

Pyr-GC-Orbitrap-MS method for the target/untargeted analysis of microplastics in air

Pyrolysis-gas chromatography coupled to Orbitrap-mass spectrometry is a novel technique that allows the low level and precise determination of microplastics in environmental samples. In this paper, we develop and assess the target and untargeted performance of Pyr-GC-Orbitrap-MS. The method was optimized for 10 plastic polymers: polymethyl methacrylate, nylon-6,6, polypropylene, nitrile butadiene rubber, polyvinyl chloride, polyethylene terephthalate, acrylonitrile butadiene styrene, polyethylene, polycarbonate, and polystyrene. Standards were home-made using a diamond driller to attain mean sizes within the range of 45-382 µm. A step-by-step optimization of the analytical procedure was carried out. First, accurate mass measurement of each polymer at 60,000 resolution was studied to select the 3 most intense and selective quantification and confirmation ions. Second, internal standard quantification was optimized, and good linearity, repeatability, and reproducibility were obtained. Blank contribution and instrumental detection limit were evaluated for each polymer. Finally, the combined and expanded uncertainty of the Pyr-GC-Orbitrap-MS method was calculated to determine the sources of variation, considering that home-made standards were used. To evaluate method performance, targeted and non-targeted analysis of indoor air samples collected from gyms and department stores were carried out. The Pyr-GC-Orbitrap-MS methodology herein described can be applied for the quantitative assessment of MPs and other substances in different matrices.

DEPArray™ single-cell technology: A validation study for forensic applications

In forensics investigations, it is common to encounter biological mixtures consisting of homogeneous or heterogeneous components from multiple individuals and with different genetic contributions. One promising mixture deconvolution strategy is the DEPArray™ technology, which enables the separation of cell populations before genetic analysis. While technological advances are fundamental, their reliable validation is crucial for successful implementation and use for casework. Thus, this study aimed to 1) systematically validate the DEPArray™ system concerning specificity, sensitivity, repeatability, and contamination occurrences for blood, epithelial, and sperm cells, and 2) evaluate its potential for single-cell analysis in the field of forensic science. Our findings confirmed the effective identification of different cell types and the correct assignment of successfully genotyped single cells to their respective donor(s). Using the NGM Detect™ Amplification Kit, the average profile completeness for diploid cells was approximately 80%, with ∼ 290 RFUs. In contrast, haploid sperm analysis yielded an average completeness of 51% referring to the haploid reference profile, accompanied by mean peak heights of ∼ 176 RFUs. Although certain alleles of heterozygous loci in diploid cells showed strong imbalances, the overall peak balances yielded acceptable values above ≥ 60% with a mean value of 72% ± 0.21, a median of 77%, but with a maximum imbalance of 9% between heterozygous peaks. Locus dropouts were considered stochastic events, exhibiting variations among donors and cell types, with a notable failure incidence observed for TH01. Within the wet-lab experimentation with >500 single cells for the validation, profiling was performed using the consensus approach, where profiles were selected randomly from all data to better mirror real casework results. Nevertheless, complete profiles could be achieved with as few as three diploid cells, while the average success rate increased to 100% when using profiles of 6-10 cells. For sperms, however, a consensus profile with completeness >90% of the autosomal diploid genotype could be attained using ≥15 cells. In addition, the robustness of the consensus approach was evaluated in the absence of the respective reference profile without severe deterioration. Here, increased stutter peaks (≥ 15%) were found as the main artifact in single-cell profiles, while contamination and drop-ins were ascertained as rare events. Lastly, the technique's potential and limitations are discussed, and practical guidance is provided, particularly valuable for cold cases, multiple perpetrator rapes, and analyses of homogeneous mixed evidence.

Application of validated UV spectrophotometric and colorimetric method to quantify minoxidil in the development of trilayer dissolving microneedle: Proof of concept in ex vivo and in vivo studies in rats

Alopecia areata (AA) is an autoimmune-induced hair loss condition, by utilizing MNX, a hair growth-promoting compound. However, minoxidil (MNX) administration's efficacy is hindered by low bioavailability and adverse effects. To enhance its delivery, Trilayer Dissolving Microneedles (TDMN) are introduced, enabling controlled drug release. The study's primary was to establish a validated UV-Vis Spectrophotometer method for Minoxidil analysis in rat skin affected by alopecia areata. This method adheres to International Conference Harmonization (ICH) and FDA guidelines, encompassing accuracy, precision, linearity, quantification limit (QL), and detection limit (DL). The validation method was conducted through two approaches, namely UV region validation using PBS and the colorimetric method in the visible region (Vis). The validated approach is then employed for assessing in vitro release, ex vivo permeation, and in vivo pharmacokinetics. Results indicate superior MNX extraction recovery using methanol compared to acetonitrile. Method C (5mL methanol) is optimal, offering high recovery with minimal solvent usage. Precision assessments demonstrate %RSD values within MNX guidelines (≤15%), affirming accuracy and reproducibility. UV-Vis spectroscopy quantifies MNX integration into TDMN, using PVA-PVP, with concentrations aligning with ICH standards (95% to 105%). In conclusion, TDMN holds promise for enhancing MNX delivery, mitigating bioavailability and side effect challenges. The validated UV-Vis Spectrophotometer method effectively analyzes MNX in skin tissues, providing insights into AA treatment and establishing a robust analytical foundation for future studies.

Validation of the German version of the DSQIID in adults with intellectual disabilities

BACKGROUND

An observer-rated screening questionnaire for dementia for people with intellectual disabilities (ID), DSQIID, was developed in the UK. So far, the German version has not yet been validated in adults with ID.

AIMS/METHODS

We validated a German version of DSQIID (DSQIID-G) among adults with ID attending a German clinic.

PROCEDURES/OUTCOMES

DSQIID-G was completed by the caregivers of 104 adults with ID at baseline (T1), 94 at six months (T2) and 83 at 12 months (T3). A Receiver Operating Curve (ROC) was used to determine the total DSQIID-G cutoff score for the best fit between sensitivity and specificity.

RESULTS

Sixteen of the 104 participants at T1 (15%) received a diagnosis of dementia. At T1, the scores among the non-dementia group ranged from 0 to 33 (mean: 6.7; SD: 7.65), and the dementia group ranged from 3 to 43 (mean: 22.12; SD: 11.6). The intergroup difference was statistically significant (W: 158; p < .001) (AUC:.89). A total score of 9 provided the best fit between sensitivity (.94) and specificity (.72).

CONCLUSIONS AND IMPLICATIONS

DSQIID-G total score can discriminate between dementia and non-dementia cases in adults with ID. A lower cutoff score with a higher sensitivity is desirable for a screening instrument.

Exploration of the psychometric properties of the EPDS-US, a validation study

INTRODUCTION

The purpose of this study was to explore the reliability and construct validity of the EPDS-US.

METHODS

To enhance the perinatal mental health screen, we adapted the Edinburgh Postnatal Depression Screen (EPDS) for application in the United States, and evaluated reliability and construct validity of the EPDS-US in a sample of 100 postpartum individuals. We explored reliability by estimating internal consistency of the scale and evaluating concurrent validity with correlations to the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder Assessment (GAD-7); and construct validity using factor analysis and discriminant validity with correlations to the Perceived Stress Scale (PSS).

RESULTS

We present both a one-factor (Cronbach's alpha of 0.83) and two-factor model consisting of depressive (Cronbach's alpha 0.76) and anxiety symptoms (Cronbach's alpha 0.78) of the EPDS-US. Related to discriminant validity, the EPDS-US and PSS exhibited a moderate correlation of 0.71. For measures of concurrent validity, correlations with the PHQ-9 and GAD-7 were moderate; 0.63 and 0.68, respectively.

CONCLUSION

The EPDS-US was adapted to enhance the perinatal mental health screening experience for populations in the US while maintaining the reliability and validity of the original Edinburgh Postnatal Depression Scale. These findings contribute to the evidence of reliability and validity of the EPDS-US in perinatal populations in the United States; presenting initial evidence supporting construct validity and concurrent validity of this newly adapted 10-item scale.

Testing the accuracy of the DRNNAGE software for age estimation in a modern Greek sample

Estimation of age-at-death from human skeletal remains is fundamental in forensic anthropology as part of the construction of the biological profile of the individual under study. At the same time, skeletal age-at-death estimation in adults is problematic due to the disparity between chronological and biological age, the important inter-individual variability at the rate of skeletal aging, and inherent biases in the available methodologies (e.g., age mimicry). A recent paper proposed a method for skeletal age-at-death estimation based on multiple anatomical traits and machine learning. A software was also created, DRNNAGE, for the easy implementation of this method. The authors of that study supported that their methods have very high repeatability and reproducibility, and the mean absolute error of the age estimation was ~6 years across the entire adult age span, which is particularly high and promising. This paper tests the proposed methodology on a modern documented Greek sample of 219 adult individuals from the Athens Collection, with age-at-death from 19 to 99 years old. The sample was split into males and females as well as into individuals under and over 50 years old. We also divided the sample in 10-year intervals. First, intra- and inter-observer error was estimated in order to assess repeatability and reproducibility of the variables employed for age-at-death estimation. Then, the validity (correct classification performance) of DRNNAGE for each anatomical region individually, as well as all combined, was evaluated on each demographic separately and on the pooled sample. According to the results, some of the variables showed very low repeatability and reproducibility, thus their use should be cautious. The DRNNAGE software showed overall highly accurate age-at-death estimates for individuals older than 50 years, but poor on younger adults, with only exception the cranial sutures, which performed surprisingly well for all age groups. Overall, these results support the importance of cross-validation and the use of population-specific methods in forensic anthropology.

Prospective validation of Sophia observation withdrawal symptoms: A paediatric delirium scale in critically ill children in Denmark

BACKGROUND

Paediatric delirium (PD) is increasingly recognised as a common disorder in critically ill children with a reported prevalence ranging from 9% to 66%. We validated the PD component of the Sophia Observation withdrawal Symptoms-Paediatric Delirium (SOS-PD) scale in a Danish setting to provide increased awareness and reliable identification of this critical condition, thereby paving the way for improved pathways to targeted delirium care.

OBJECTIVE

The objectives of this study were to criterion validate the PD component of the SOS-PD screening tool by comparing blinded psychiatric and nurse assessments and to estimate the prevalence of delirium in critically ill children in a Danish context.

METHODS

A prospective observational study was performed on critically ill children aged between 3 m and 18 y, admitted to an intensive care unit, with a hospital stay of 48 h or more. Assessments took place on a fixed weekday over an 18-month period. To test accuracy and criterion validity, bedside nurses' SOS-PD assessments were compared to the reference standard, a diagnostic assessment performed by a child psychiatrist according to the Diagnostic and Statistical Manual-V criteria by use of the Vanderbilt Assessment of Delirium in Infants and Children.

RESULTS

We included 141 children in the study, 30 (21%) of whom were diagnosed with delirium by the child psychiatrist. The accuracy of the delirium diagnosis was 93.6% (95% confidence interval [CI]: 88.3-97.1) among the nurses' SOS-PD assessments compared to the reference standard. The SOS-PD demonstrated a high sensitivity of 83.3% (95% CI: 65.3-94.4) and a high specificity of 96.4% (95% CI: 91.0-99.0) with five false-negative and four false-positive cases.

CONCLUSION

The PD component of the SOS-PD tool has good accuracy and validity for assessments performed by nurses compared to a child psychiatrist's diagnosis in critically ill children in a Danish setting. We recommend the use of the SOS-PD instrument in clinical practice.

The ad-libitum taste test as measure of momentary alcohol use in the laboratory: an investigation of construct validity and confounding factors

RATIONALE

The ad-libitum taste test is a widely used covert measure of motivation to consume alcohol in the laboratory. However, studies on its construct validity and potential confounding factors are scarce.

OBJECTIVES

This study aimed to evaluate the construct validity of the ad-libitum taste test by examining the association of ad-libitum alcohol consumption with typical alcohol use and craving, and investigating potential moderation by trait anxiety, depressiveness, current mood, and drinking motives.

METHODS

A sample of 264 young male individuals were offered two 0.33 l glasses of beer. Participants were instructed to rate the characteristics of each drink, while the percentage of beverages containing alcohol consumed was assessed. Associations of ad-libitum consumption with typical alcohol use and craving were assessed using non-parametric and piecewise regressions. Moreover, moderator analysis with trait anxiety, depressiveness, current mood, and drinking motives was carried out.

RESULTS

Ad-libitum alcohol consumption was associated with typical alcohol use and alcohol craving. However, these associations decreased at high consumption levels. Associations between ad-libitum consumption, typical alcohol use, and craving were stable across several conditions, except that the association between ad-libitum consumption and craving increased with higher social, conformity, and coping drinking motives.

CONCLUSIONS

The ad-libitum taste test appears to be a valid measure of the motivation to drink alcohol in laboratory studies in young male adults, although this validity might be compromised at high levels of ad-libitum consumption. Consideration of these factors can contribute to further refining the ad-libitum taste test as a valuable tool for assessing motivation to consume alcohol in laboratory studies.

Primary Hyperoxaluria Screening and Monitoring: Quantitative Measurement of Plasma Oxalate by Gas Chromatography-Mass Spectrometry With High Sensitivity

Background

Plasma oxalate measurements can be used for the screening and therapeutic monitoring of primary hyperoxaluria. We developed a gas chromatography-mass spectrometry (GC-MS) assay for plasma oxalate measurements with high sensitivity and suitable testing volumes for pediatric populations.

Methods

Plasma oxalate was extracted, derivatized, and analyzed by GC-MS. We measured the ion at m/z 261.10 to quantify oxalate and the 13C2-oxalate ion (m/z: 263.15) as the internal standard. Method validation included determination of the linear range, limit of blank, limit of detection, lower limit of quantification, precision, recovery, carryover, interference, and dilution effect. The cut-off value between primary and non-primary hyperoxaluria in a pediatric population was analyzed.

Results

The detection limit was 0.78 μmol/L, and the linear range was up to 80.0 μmol/L. The between-day precision was 5.7% at 41.3 μmol/L and 13.1% at 1.6 μmol/L. The carryover was <0.2%. The recovery rate ranged from 90% to 110%. Interference analysis showed that Hb did not interfere with plasma oxalate quantification, whereas intralipids and bilirubin caused false elevation of oxalate concentrations. A cut-off of 13.9 μmol/L showed 63% specificity and 77% sensitivity, whereas a cut-off of 4.15 μmol/L showed 100% specificity and 20% sensitivity. The minimum required sample volume was 250 μL. The detected oxalate concentrations showed interference from instrument conditioning, sample preparation procedures, medications, and various clinical conditions.

Conclusions

GC-MS is a sensitive assay for quantifying plasma oxalate and is suitable for pediatric patients. Plasma oxalate concentrations should be interpreted in a clinical context.

Development and validation of Malaysian one stop crisis center service quality instrument (OSCC-Qual) for domestic violence management

One Stop Crisis Center (OSCC) is a multi-sectorial center aimed to provide medical, social, legal, police and shelter services to survivors of domestic violence, rape, sexual assault, sodomy and child abuse. Although OSCCs have been established for almost three decades in different parts of the world including in Malaysia, there is a lack of a validated instrument to measure the service quality rendered in OSCCs. A validated instrument known as OSCC-Qual was developed using a 5-stage approach where (1) in stage 1, group discussions were conducted among all authors to identify potential items for the instrument; (2) in stage 2, content validation was performed by 13 experts using content validity index and modified kappa; (3) in stage 3, exploratory factor analysis was performed by 141 healthcare staff with experience in managing OSCC cases to validate the items as well as to identify the number of factors in the instrument; (4) in stage 4, confirmatory factor analysis was performed by 110 domestic violence survivors to ascertain the validity of the factors and items retained in stage 3 and (5) in stage 5, forward and backward translation into local Malay and Chinese languages was performed. Results: In stage 1, a total of 42 items were identified. No item was deleted in stage 2. In stage 3, a total of 7 factors (i.e., "information provision", "competency of staff", "professionalism", "supportive environment", "attitude of staff", "multi-sectorial coordination" and "tangibles") were identified. Four items were deleted due to poor factor loading. In stage 4, another 3 items were iteratively removed due to poor factor loading. Discriminant validity was good. Conclusion: With the availability of the 7-factor and 35-item OSCC-Qual instrument, it is hoped that the efficiency of OSCC in achieving its philosophical objectives after three decades of implementation can be unraveled and remedial actions can be taken, if necessary.

Translation and validation of traditional Chinese version of the pediatric eating assessment Tool-10

BACKGROUND

/Purpose: The Pediatric Eating Assessment Tool-10 (Pedi-EAT-10) is a caregiver-administrated subjective questionnaire for evaluating swallowing and feeding disorders among children. This study translated the Pedi-EAT-10 into Traditional Chinese and tested the translated version's reliability and validity.

METHODS

Pedi-EAT-10 was translated into Traditional Chinese by experts and finalized after discussion and testing. A total of 168 participants, consisting of 32 children with dysphagia from a tertiary medical center and 136 healthy controls from its Children Care Center for Employees, were recruited. All participants were assessed by an otolaryngologist and speech-language pathologist. The reliability, validity, and efficacy of the translated Pedi-EAT-10 were analyzed to ensure it could be used to identify pediatric dysphagia and feeding problems.

RESULTS

The Traditional Chinese version of the Pedi-EAT-10 had significant clinical discriminative validity between the dysphagia group and the control group (total score = 9.6 vs. 2.6, P < 0.001), acceptable test-retest reliability (intraclass correlation = 0.63), and excellent internal consistency (Cronbach's α = 0.91 for the entire cohort). The overall performance of the test for distinguishing children with dysphagia from normal controls was acceptable, and the area under the curve was 74.8% (sensitivity = 71.9%; specificity = 69.9%). The optimal cutoff score was ≥3 on the Youdex index.

CONCLUSIONS

The Traditional Chinese version of the Pedi-EAT-10 has fair reliability and validity and can be quickly and easily completed by caregivers. The translated Ped-EAT-10 can be used as a first-line tool for assessing the need for further referral and instrumental examination.

Validation of the RBP-9801 oscillometric blood pressure monitor in the general population according to the association for the Advancement of Medical Instrumentation/European Society of Hypertension/ International Organization for Standardization Universal Standard

The aim of this study was to evaluate the accuracy of the single upper-arm cuff oscillometric blood pressure (BP) monitor RBP-9801 developed for office and home BP measurement in the general population according to the Association for the Advancement of Medical Instrumentation/European Society of Hypertension/International Organization for Standardization (AAMI/ESH/ISO) Universal Standard (ISO 81060-2:2018). Subjects were recruited to fulfil the age, gender, BP and cuff distribution criteria of the AAMI/ESH/ISO Universal Standard in general population using the same arm sequential BP measurement method. A total of 105 subjects were recruited and 85 were analyzed. For validation criterion 1, the mean ± SD of the differences between the test device and reference BP readings was 2.3 ± 6.4/3.1 ± 5.8 mmHg (systolic/diastolic). For criterion 2, the SD of the mean BP differences between the test device and reference BP per subject was 5.24/5.03 mmHg (systolic/diastolic). The conclusion is that the RBP-9801 oscillometric device for office and home BP measurement fulfilled all the requirements of the AAMI/ESH/ISO Universal Standard (ISO 81060-2:2018) in the general population and can be recommended for clinic and self-use at home.

Days alive and out of hospital for adult female and male cardiac surgery patients: a population-based cohort study

BACKGROUND

Research shows women experience higher mortality than men after cardiac surgery but information on sex-differences during postoperative recovery is limited. Days alive and out of hospital (DAH) combines death, readmission and length of stay, and may better quantify sex-differences during recovery. This main objective is to evaluate (i) how DAH at 30-days varies between sex and surgical procedure, (ii) DAH responsiveness to patient and surgical complexity, and (iii) longer-term prognostic value of DAH.

METHODS

We evaluated 111,430 patients (26% female) who underwent one of three types of cardiac surgery (isolated coronary artery bypass [CABG], isolated non-CABG, combination procedures) between 2009 - 2019. Primary outcome was DAH at 30 days (DAH30), secondary outcomes were DAH at 90 days (DAH90) and 180 days (DAH180). Data were stratified by sex and surgical group. Unadjusted and risk-adjusted analyses were conducted to determine the association of DAH with patient-, surgery-, and hospital-level characteristics. Patients were divided into two groups (below and above the 10th percentile) based on the number of days at DAH30. Proportion of patients below the 10th percentile at DAH30 that remained in this group at DAH90 and DAH180 were determined.

RESULTS

DAH30 were lower for women compared to men (22 vs. 23 days), and seen across all surgical groups (isolated CABG 23 vs. 24, isolated non-CABG 22 vs. 23, combined surgeries 19 vs. 21 days). Clinical risk factors including multimorbidity, socioeconomic status and surgical complexity were associated with lower DAH30 values, but women showed lower values of DAH30 compared to men for many factors. Among patients in the lowest 10th percentile at DAH30, 80% of both females and males remained in the lowest 10th percentile at 90 days, while 72% of females and 76% males remained in that percentile at 180 days.

CONCLUSION

DAH is a responsive outcome to differences in patient and surgical risk factors. Further research is needed to identify new care pathways to reduce disparities in outcomes between male and female patients.

A first look at the reliability, validity and responsiveness of L-PF-35 dyspnea domain scores in fibrotic hypersensitivity pneumonitis

BACKGROUND

Dyspnea impairs quality of life (QOL) in patients with fibrotic hypersensitivity pneumonitis (FHP). The Living with Pulmonary Fibrosis questionnaire (L-PF) assesses symptoms, their impacts and PF-related QOL in patients with any form of PF. Its scores have not undergone validation analyses in an FHP cohort.

METHODS

We used data from the Pirfenidone in FHP trial to examine reliability, validity and responsiveness of the L-PF-35 Dyspnea domain score (Dyspnea) and to estimate its meaningful within-patient change (MWPC) threshold for worsening. Lack of suitable anchors precluded conducting analyses for other L-PF-35 scores.

RESULTS

At baseline, Dyspnea's internal consistency (Cronbach's coefficient alpha) was 0.85; there were significant correlations with all four anchors (University of California San Diego Shortness of Breath Questionnaire scores r = 0.81, St. George's Activity domain score r = 0.82, percent predicted forced vital capacity r = 0.37, and percent predicted diffusing capacity of the lung for carbon monoxide r = 0.37). Dyspnea was significantly different between anchor subgroups (e.g., lowest percent predicted forced vital capacity (FVC%) vs. highest, 33.5 ± 18.5 vs. 11.1 ± 9.8, p = 0.01). There were significant correlations between changes in Dyspnea and changes in anchor scores at all trial time points. Longitudinal models further confirmed responsiveness. The MWPC threshold estimate for worsening was 6.6 points (range 5-8).

CONCLUSION

The L-PF-35 Dyspnea domain appears to possess acceptable psychometric properties for assessing dyspnea in patients with FHP. Because instrument validation is never accomplished with one study, additional research is needed to build on the foundation these analyses provide.

TRIAL REGISTRATION

The data for the analyses presented in this manuscript were generated in a trial registered on ClinicalTrials.gov; the identifier was NCT02958917.

Evaluation of particulate organic carbon from MODIS-Aqua in a marine-coastal water body

La Paz Bay (LPB) in Mexico is one of the largest marine-coastal bodies of water in the Gulf of California (GC) and is ecologically important for the feeding, reproduction, and refuge of marine species. Although particulate organic carbon (POC) is an important reservoir of oceanic carbon and an indicator of productivity in the euphotic zone, studies in this region are scarce. This study evaluates the performance of satellite-derived POC in LPB from January 2003 to December 2020. The metrics obtained for COP ( RMSE = 33.8 mg m - 3 ;P bias = 29.6 % yr P = 0.4 con p < 0.05 ), Chla-a ( RMSE = 0.23 mg m - 3 ;P bias = - 4.3 % yr P = 0.94 con p < 0.05 ), and SST ( RMSE = 2 . 3 ∘ C ;P bias = - 2.2 % yr P = 0.92 con p < 0.05 ) establish that although in some cases there was a slight over/underestimation, the satellite estimates consistently represent the variability and average values measured in situ. On the other hand, the spatio-temporal analysis of the POC allowed us to identify two seasons with their respective transition periods and five subregions in which the POC is characterized by having its maximum variability; two of these coincide with the locations of the eddies reported for the winter and summer seasons in the LPB, while the following three are located: one in the coastal zone and in the two areas in which the LPB interacts with the GC. The associations, variability nodes, and multiple linear regression analysis suggest that POC fluctuations in the LPB respond mainly to biological processes and, to some extent, to the seasonality of SST and wind. Finally, our results justify the use of the MODIS-Aqua satellite POC for studies in marine-coastal water bodies with similar characteristics to the LPB and suggest that this water body can be considered a reservoir for the marine region of northwestern Mexico.

Potentials and limitations of a food group-based algorithm to assess dietary nutrient intake of women in rural areas in Tanzania

The aim of this study was to evaluate the accuracy of nutrient intake assessment with the food group-based algorithm "Calculator of Inadequate Micronutrient Intake" (CIMI) in comparison to the established nutrition software NutriSurvey. Using Food Frequency Questionnaires and 24-h dietary recalls of 1010 women from two rural districts in Tanzania, 23 relevant typical Tanzanian food groups were identified and subsequently the dietary protocols assessed via CIMI algorithm were compared by bivariate correlations and Bland-Altman analysis with the results of the NutriSurvey software (reference) and were set in relation to blood biomarkers of 666 participants. CIMI and NutriSurvey calculations regarding macro- and micronutrient intakes were similar. The Bland-Altman analyses and correlation coefficients of energy (0.931), protein (0.898), iron (0.775) and zinc (0.838) confirm the agreement of both calculations. The food group based CIMI algorithm is a practical tool to identify the inadequacy of macro- and micronutrient intake at population level.

Development and validation of the rheumatoid arthritis scale among the system of quality of life instruments for chronic diseases QLICD-RA (V2.0)

Rheumatoid Arthritis is a more serious threatening to people and suitable for QOL measurement. A few specific QOL instruments are available without considering Chinese culture. The present study was aimed to develop and validate the Rheumatoid Arthritis Scale among the System of Quality of Life Instruments for Chronic Diseases (QLICD-RA V2.0). The data collected from 379 patients with RA was used to evaluate the psychometric properties of the scale. The reliability was evaluated by the internal consistency Cronbach's α, test-retest reliability Pearson correlation r and intra-class correlation (ICC). We evaluated the construct validity and criteria-related validity by correlation analysis and structural equation modeling. We compared the differences in scores of QLICD-RA before and after treatment and used the Standard Response Mean (SRM) to assess the responsiveness. The results showed that the internal consistency coefficient Cronbach's α values were greater than 0.70. The correlations r and ICCs were greater than 0.80. The correlation analysis and structural equation modeling confirmed good construct validity and criterion-related validity. The SRM ranges from 0.07 to 0.27 for significant domains/facets. It concluded that QLICD-RA (2.0) is a reliable and valid instrument to measure QOL among patients with RA.

Adaptation and validation study of the Indonesian version of the Global Psychotrauma Screen in an undergraduate student population

BACKGROUND

The high incidence of potentially traumatic events (PTEs) in Indonesia warrants early identification of those with probable trauma-related disorders in order to tailor prevention and intervention for trauma-related symptoms.

OBJECTIVES

This study aims to adapt and validate a novel brief transdiagnostic screener, the Global Psychotrauma Screen (GPS), in Indonesian undergraduate students.

METHODS

An online survey was administered among Indonesian undergraduate students (N = 322). Exploratory factor analysis, reliability analyses, clinical validity analyses, and correlational analyses were performed to evaluate the construct validity, reliability, clinical validity, and convergent-divergent validity of the Indonesian GPS. Hierarchical multiple regression was conducted to assess the relationship between risk factors and trauma-related symptoms. The relationship between four categories of trauma-related symptom severity and social/work functioning was measured using Analysis of Covariance.

RESULTS

Exploratory factor analysis yielded a single-factor solution. The Indonesian GPS demonstrated good internal consistency, test-retest correlation, and absolute agreement, indicating good reliability. The Indonesian GPS also had an acceptable area under the curve, sensitivity, and specificity for a probable diagnosis of Post-Traumatic Stress Disorder (PTSD), Complex-PTSD (CPTSD), depression, and generalized anxiety disorder (GAD). We also established evidence for the convergent and divergent validity of GPS. The GPS risk factors (low psychological resilience, other stressful events, history of mental illness, and low social support) contributed to predicting trauma-related symptoms after controlling for gender, age, employment status, and faculty background. Additionally, in comparison to participants from the mild and low categories of GPS symptoms scores, participants from the severe and moderate category reported impaired lowered social/work functioning.

CONCLUSION

The current findings indicate that the Indonesian GPS is a valid and reliable transdiagnostic trauma screener for Indonesian undergraduate students. This first comprehensive validation of the GPS in Indonesia calls for more research in Lower-middle Income Countries (LMICs) as a way towards prevention and early intervention for trauma-related symptoms.

Validation of actigraphy sleep metrics in children aged 8 to 16 years: considerations for device type, placement and algorithms

BACKGROUND

Actigraphy is often used to measure sleep in pediatric populations, despite little confirmatory evidence of the accuracy of existing sleep/wake algorithms. The aim of this study was to determine the performance of 11 sleep algorithms in relation to overnight polysomnography in children and adolescents.

METHODS

One hundred thirty-seven participants aged 8-16 years wore two Actigraph wGT3X-BT (wrist, waist) and three Axivity AX3 (wrist, back, thigh) accelerometers over 24-h. Gold standard measures of sleep were obtained using polysomnography (PSG; Embletta MPRPG, ST + Proxy and TX Proxy) in the home environment, overnight. Epoch by epoch comparisons of the Sadeh (two algorithms), Cole-Kripke (three algorithms), Tudor-Locke (four algorithms), Count-Scaled (CS), and HDCZA algorithms were undertaken. Mean differences from PSG values were calculated for various sleep outcomes.

RESULTS

Overall, sensitivities were high (mean ± SD: 91.8%, ± 5.6%) and specificities moderate (63.8% ± 13.8%), with the HDCZA algorithm performing the best overall in terms of specificity (87.5% ± 1.3%) and accuracy (86.4% ± 0.9%). Sleep outcome measures were more accurately measured by devices worn at the wrist than the hip, thigh or lower back, with the exception of sleep efficiency where the reverse was true. The CS algorithm provided consistently accurate measures of sleep onset: the mean (95%CI) difference at the wrist with Axivity was 2 min (-6; -14,) and the offset was 10 min (5, -19). Several algorithms provided accurate measures of sleep quantity at the wrist, showing differences with PSG of just 1-18 min a night for sleep period time and 5-22 min for total sleep time. Accuracy was generally higher for sleep efficiency than for frequency of night wakings or wake after sleep onset. The CS algorithm was more accurate at assessing sleep period time, with narrower 95% limits of agreement compared to the HDCZA (CS:-165 to 172 min; HDCZA: -212 to 250 min).

CONCLUSION

Although the performance of existing count-based sleep algorithms varies markedly, wrist-worn devices provide more accurate measures of most sleep measures compared to other sites. Overall, the HDZCA algorithm showed the greatest accuracy, although the most appropriate algorithm depends on the sleep measure of focus.

Understanding the Dynamics of Polymer Extrusion: Simulation of Thermoplastics Processing with Planetary Roller Extruders

Resource efficient processing of polymers is of paramount importance to minimize energy consumption, processing time, and material losses in the polymer industry. This study is concerned with polymer processing in planetary roller extruders. A three-dimensional numerical flow simulation was tailored to understand the polymer flow through the extruder in detail. Using the simulation software ANSYS Polyflow, we quantified both directly measurable process parameters, such as pressure build-up, and more intangible parameters, such as material shear. By varying operational and material parameters in a sensitivity analysis, we showed that the dynamics, material stress and pressure build-up are controlled primarily by the number of spindles and their rotational speed. Notably, this work provides the first successful validation of a 3D simulation of a polymer flow in a planetary roller extruder against actual experimental data. The simulation showed robust agreement between the simulated and experimental values, provided that a critical backpressure length is reached. This computational approach minimizes labor-intensive experimental testing in polymer processing.

The psychometric properties of the Arabic version of the dieting beliefs scale (DBS)

Background

There are relatively few data about the association between locus of control and weight loss in Arabic populations. A tool does exist, the Dieting Belief Scale (DBS), that was designed to measure individuals' beliefs regarding their ability to control their body weight. The aim of this study was to translate this tool into Arabic and to evaluate its psychometric properties.

Methods

The forward translation of the DBS from English to Arabic was completed by two professional bilingual translators, while the back translation from Arabic to English was independently performed by another two different professional bilingual translators. An online survey using the tool was then completed by 245 participants, fully aware of the study's purpose. Psychometric analyses were subsequently conducted to assess the reliability and validity of the Arabic DBS.Internal consistency was examined using Cronbach's α and McDonald's ω coefficients. Test-retest reliability was also assessed. Confirmatory factor analysis was employed to evaluate the fit of a three-factor model, with indices including Comparative Fit Index (CFI), Tucker Lewis Index (TLI), Root Mean Square Error of Approximation (RMSEA), and Standardized Root Mean Square Residual (SRMR). Convergent validity was assessed by examining the correlation between the Arabic DBS and the Eating Attitude Test (EAT-26) previously translated into Arabic, the latter identifying attitudes, feelings and behaviors related to eating.

Results

The Arabic translated DBS scale demonstrated high translation accuracy and content validity estimates. Cronbach's α and McDonald's ω reliability coefficients for the translated scale were approximately 0.91. Test-retest reliability was 0.96. The three-factor model showed an acceptable fit (CFI = 0.93, TLI = 0.92, RMSE = 0.08, SRMR = 0.06). The Arabic version of the DBS was found to have good convergent validity, as evidenced by the significant correlation between the EAT-26 and DBS questionnaires (r = 0.53, p < 0.01).

Conclusion

The Arabic version of the DBS is highly reliable and has sufficient content validity to measure belief about personal ability to control one's weight.

Development of a robust cell-based potency assay for a coxsackievirus A21 oncolytic virotherapy

Oncolytic viruses (OV) are part of a burgeoning field of investigational oncolytic therapy (OT), in which lytic viruses dissolve advanced tumors productively and specifically. One such OT is a Coxsackievirus A21 (CVA21) based OV that is currently under clinical evaluation. A tissue culture infectious dose (TCID50) assay was used for CVA21 potency release and stability testing in early clinical development. The titer measured in this method was an extrapolated value from cytopathic effect (CPE) observed during the serial dilution but doesn't represent direct viral killing of cells. Moreover, the assay was not deemed to be optimal to carry into late phase clinical development due to limitations in assay precision, turn-around time, and sample throughput. To address these points, we developed a plaque assay to measure viral plaque forming units to measure the potency value for drug substance (DS), drug product (DP) and virus seed (master and working) stocks. In this manuscript, we describe the steps taken to develop this plaque assay for the late-stage clinical development, which include the assay qualification, validation, and robustness protocols, and describe statistical methods for data analysis. Moreover, the method was validated for linearity, accuracy, precision, and specificity. Furthermore, the plaque assay quantifies OV infectivity with better precision (32% vs 58%), with higher sample throughput (22 samples/week vs 3 samples/week) and shorter assay turnaround time (4 days vs 7 days) than the TCID50 method. This assay development strategy can provide guidance for the development of robust cell-based potency methods for OVs and other infectious viral products.

Measuring General Health Literacy in Chinese adults: validation of the HLS19-Q12 instrument

BACKGROUND

Health literacy measurement lays a solid foundation to identify associations with health outcomes and monitor population health literacy levels over time. In mainland China, most existing health literacy instruments are either knowledge-based or practice-based, making health literacy results incomparable between China and other countries. This study aimed to examine the reliability and validity of the 12-item Health Literacy Population Survey (HLS19-Q12) in a general population of Chinese adults.

METHODS

A cross-sectional study was conducted to recruit primary carers of students from 11 schools in Zhengzhou, Henan Province, using convenience cluster sampling. Participants completed an online self-administered survey that collected information on key sociodemographics, health literacy (HLS19-Q12 and a comparison tool: Health Literacy Questionnaire (HLQ)), and health-related outcomes. Using the COnsensus-based Standards for the selection of health status Measurement Instruments (COSMIN) checklist as a guideline, we tested internal consistency, test-retest reliability, content validity, structural validity, concurrent predictive validity, and convergent validity of the HLS19-Q12.

RESULTS

Overall, 14,184 participants completed the full survey. The HLS19-Q12 showed excellent internal consistency (Cronbach's α = 0.93), moderate test-retest reliability (intra-class correlation coefficient = 0.54), satisfactory content validity (based on the 12-matrix health literacy model), and strong structural validity (comparative fit index = 0.94, Tucker and Lewis's index of fit = 0.93, root mean square error of approximation = 0.095). Concurrent predictive validity results showed health literacy was associated with both health determinants and health-related outcomes. The HLS19-Q12 had weak to strong correlations (coefficients = 0.24 to 0.42) with the nine scales of the HLQ. Respondents had an average score of 81.6 (± 23.0) when using the HLS19-Q12, with 35.0% and 7.5% having problematic and inadequate levels of health literacy, respectively.

CONCLUSIONS

The HLS19-Q12 is a reliable and valid instrument to measure health literacy in our sample. Further validation is needed with a more nationally representative sample of Chinese adults. The HLS19-Q12 could be used as a comprehensive, skills-based, and easy-to-administer health literacy assessment tool integrated into population surveys and intervention evaluations.

Assessment and correlates of aloneliness among Indonesian adolescents

Introduction

The goals of this study were to: (1) adapt and validate a measure of aloneliness (Solitude and Aloneliness Scale; SolAS) for use among Indonesian adolescents; (2) examine the associations between aloneliness and indices of well-being in this unique developmental and cultural context; and (3) explore possible grade and gender effects.

Methods

Participants were Indonesian adolescents aged 11-18 years (M = 14.13 years, SD = 1.62; 58.51% girls) who completed self-report assessments of the adapted SolAS (newly created Indonesian translation), as well as indices of adjustment (e.g., well-being, basic psychological need satisfaction).

Results

Among the results, the Indonesian version of the SolAS demonstrated good psychometric properties (e.g., factor structure, good internal reliability) and initial evidence of validity (e.g., significant negative correlations with measures of psychological well-being and basic psychological needs satisfaction). Girls reported higher levels of aloneliness than boys, but no significant grade differences emerged.

Conclusions

The SolAS evidenced good psychometric properties and evidence of validity in a sample of Indonesian adolescents, suggesting it is desirable for cross-cultural research.

Enhancing LOD determination in gas chromatography: Validating the Hubaux-Vos method for gas concentration measurement

The limit of detection (LOD) is a crucial measure in analytical methods, representing the smallest amount of a substance that can be distinguished from background noise. In the realm of gas chromatography (GC), however, determining LOD can be quite subjective, leading to significant variability among researchers. In this study, we validate the Hubaux-Vos method, an International Standards Organization(ISO)-approved approach for determining LOD in gas concentration measurements, using a GC equipped with a discharge ionization detector (DID) and a dynamic dilution system. We employ a gas mixture certified reference material (CRM) of CO, CH4, and CO2 at various concentrations to generate calibration curves for each gas. Subsequently, we estimate the LODs for each gas using the Hubaux-Vos method. Surprisingly, our findings indicate a notable difference between the LODs calculated using the Hubaux-Vos method and those confirmed through experiments. This highlights the importance of critically examining the theoretical foundations of LOD determination. We strongly recommend researchers to scrutinize the principles guiding LOD determination. The method proposed in this study offers an effective way to rigorously validate theoretical approaches for estimating LODs in gas concentration measurements using GC.

Validity and reliability of the Turkish version of the transition of primiparas becoming mothers scale

BACKGROUND

The transition to motherhood is an important life event in a woman's life and represents an important developmental process that brings physical, psychological and social changes to gain a new role. However, research on the transition to motherhood in Turkish society is scarce. There is a need for a comprehensive, practical and reliable tool to evaluate the transition to motherhood in primiparous mothers. This study evaluated the reliability and validity of the Turkish version of the Transition of Primiparous Becoming Mothers Scale (TMP-S) to evaluate the transition process of primiparous mothers to motherhood.

METHODS

This methodological research was carried out in obstetrics and gynecology outpatient clinics, pediatric outpatient clinics, and family health centers of a hospital in Türkiye. The sample consisted of primiparous mothers of 0 to 6- month-old babies who visited clinics and family health centers for routine postnatal examinations (n ​​= 305). After evaluating the language equivalence and content validity of the scale, test-retest reliability, internal consistency and construct validity were examined. Factor analysis, Pearson's correlation, retest reliability, and Cronbach's alpha were employed to evaluate structural validity and reliability.

RESULTS

The final TPM-S had two dimensions with 25 items. Exploratory factor analysis revealed a two-factor solution, which accounted for 59.276% of the variance. Confirmatory factor analysis showed that the model fit of the two-factor model also reached a satisfactory model ft after modification. The comparative fit index was 0.894, the Tucker‒Lewis index was 0.882, and the root mean square error of approximation was 0.079. The content validity index of the scale ranged from 0.56 ~ 0.77. The Cronbach's alpha coefficient was 0.93 for the total scale, and the test-retest reliability was 0.96.

CONCLUSIONS

It is a valid and reliable tool for evaluating the transition to motherhood among primiparous mothers of 0 to 6 month-old babies in Türkiye. Turkish researchers and healthcare professionals can routinely apply this measurement tool to primiparous mothers in the first six months after birth to evaluate their transition to motherhood.

The assessment of dietary carotenoid intake of the Cardio-Med FFQ using food records and biomarkers in an Australian cardiology cohort: a pilot validation

Dietary carotenoids are associated with lower risk of CHD. Assessment of dietary carotenoid intake using questionnaires can be susceptible to measurement error. Consequently, there is a need to validate data collected from FFQs which measure carotenoid intake. This study aimed to assess the performance of the Cardio-Med Survey Tool (CMST)-FFQ-version 2 (v2) as a measure of dietary carotenoid intake over 12-months against plasma carotenoids biomarkers and 7-Day Food Records (7DFR) in an Australian cardiology cohort. Dietary carotenoid intakes (β- and α-carotene, lycopene, β-cryptoxanthin and lutein/zeaxanthin) were assessed using the 105-item CMST-FFQ-v2 and compared to intakes measured by 7DFR and plasma carotenoid concentrations. Correlation coefficients were calculated between each dietary method, and validity coefficients (VCs) were calculated between each dietary method and theoretical true intake using the 'methods of triads'. Thirty-nine participants aged 37-77 years with CHD participated in the cross-sectional study. The correlation between FFQ and plasma carotenoids were largest and significant for β-carotene (0.39, p=0.01), total carotenoids (0.37, p=0.02) and β-cryptoxanthin (0.33, p=0.04), with weakest correlations observed for α-carotene (0.21, p=0.21) and lycopene (0.21, p=0.21). The FFQ VCs were moderate (0.3-0.6) or larger for all measured carotenoids. The strongest were observed for total carotenoids (0.61) and β-carotene (0.59), while the weakest were observed for α-carotene (0.33) and lycopene (0.37). In conclusion, the CMST-FFQ-v2 measured dietary carotenoids intakes with moderate confidence for most carotenoids, however, there was less confidence in ability to measure α-carotene and lycopene intake, thus further research is warranted using a larger sample.

Cultural adaptation and validation of the caring behaviors assessment tool into Spanish

BACKGROUND

The aim of the research was to translate, culturally adapt and validate the Caring Behaviors Assessment (CBA) tool in Spain, ensuring its appropriateness in the Spanish cultural context.

METHODS

Three-phase cross-cultural adaptation and validation study. Phase 1 involved the transculturation process, which included translation of the CBA tool from English to Spanish, back-translation, and refinement of the translated tool based on pilot testing and linguistic and cultural adjustments. Phase 2 involved training research assistants to ensure standardized administration of the instrument. Phase 3 involved administering the transculturally-adapted tool to a non-probabilistic sample of 402 adults who had been hospitalized within the previous 6 months. Statistical analyses were conducted to assess the consistency of the item-scale, demographic differences, validity of the tool, and the importance of various caring behaviors within the Spanish cultural context. R statistical software version 4.3.3 and psych package version 2.4.1 were used for statistical analyses.

RESULTS

The overall internal consistency of the CBA tool was high, indicating its reliability for assessing caring behaviors. The subscales within the instrument also demonstrated high internal consistency. Descriptive analysis revealed that Spanish participants prioritized technical and cognitive aspects of care over emotional and existential dimensions.

CONCLUSIONS

The new version of the tool proved to be valid, reliable and culturally situated, which will facilitate the provision of objective and reliable data on patients beliefs about what is essential in terms of care behaviors in Spain.

Development of a validated assessment tool for medical students using simulated patients: an 8-year panel survey

BACKGROUND

The use of simulated patients (SPs) to assess medical students' clinical performance is gaining prominence, underscored by patient safety perspective. However, few reports have investigated the validity of such assessment. Here, we examined the validity and reliability of an assessment tool that serves as a standardized tool for SPs to assess medical students' medical interview.

METHODS

This longitudinal survey was conducted at Keio University School of Medicine in Japan from 2014 to 2021. To establish content validity, the simulated patient assessment tool (SPAT) was developed by several medical education specialists from 2008 to 2013. A cohort of 36 SPs assessed the performance of 831 medical students in clinical practice medical interview sessions from April 2014 to December 2021. The assessment's internal structure was analyzed using descriptive statistics (maximum, minimum, median, mean, and standard deviation) for the SPAT's 13 item total scores. Structural validity was examined with exploratory factor analysis, and internal consistency with Cronbach's alpha coefficients. The mean SPAT total scores across different SPs and scenarios were compared using one way analysis of variance (ANOVA). Convergent validity was determined by correlating SPAT with the post-clinical clerkship obstructive structured clinical examination (post-CC OSCE) total scores using Pearson's correlation coefficient.

RESULTS

Of the 831 assessment sheets, 36 with missing values were excluded, leaving 795 for analysis. Thirty-five SPs, excluding one SP who quit in 2014, completed 795 assessments, for a response rate of 95.6%. Exploratory factor analysis revealed two factors, communication and physician performance. The overall Cronbach's alpha coefficient was 0.929. Significant differences in SPAT total scores were observed across SPs and scenarios via one-way ANOVA. A moderate correlation (r =.212, p <.05) was found between SPAT and post-CC OSCE total scores, indicating convergent validity.

CONCLUSIONS

Evidence for the validity of SPAT was examined. These findings may be useful in the standardization of SP assessment of the scenario-based clinical performance of medical students.

Development and validation of burnout factors questionnaire in the operating room nurses

Nurses may experience burnout more than other professions. Occupational burnout is a serious concern considering the importance of nurses' jobs in patient care. This study was carried out with the aim of designing and validating the questionnaire of burnout factors in the operating room nurses. Mixed method study was done in two qualitative and quantitative phases in 2022 on Iranian operating room nurses. In the first stage, the concept of operating room nurses' burnout was explained using interviews and literature review, and items were generated. In the second stage, the face validity, content and construct validity of the questionnaire was examined with 342 operating room nurses, and also the reliability of the questionnaire was tested using internal consistency (Cronbach's alpha) and stability (test-retest). After conducting the interview and literature review, 65 questions were extracted. Based on face validity, 4 items were modified. After content validity, 40 items remained. In construct validity, after exploratory factor analysis, 34 items with 5 dimensions were extracted. These dimensions included Organizational, Individual, Interpersonal, Occupational Nature and Managerial factors. Cronbach's alpha and intra-class correlation coefficient were equal to 0.937 and 0.946, respectively. The designed tool based on understanding the concept of burnout in operating room nurses has appropriate and acceptable validity and reliability. Therefore, it can be used to measure burnout in operating room nurses.

Construction and Validation of the Belief in Divine Retribution Scale for Pakistani Muslims

The purpose of the study was to construct and validate a Belief in Divine Retribution Scale for the Pakistani Muslim population. The process of construction and validation was completed by following standardized guidelines for scale construction (Boateng et al., 2018). The present study was carried out in four phases. In phase I, the task of item generation was completed through literature review and interviews (inductive and deductive approaches). Phase II aimed at exploration of factor structure. Exploratory factor analysis was carried out on a sample of seven hundred Muslim participants. Data for EFA were collected through a purposive sampling technique, which comprised both men (n = 339) and women (n = 361) with an age range of 18 to 69 years. Results of EFA revealed a two-factor structure with a cumulative variance of 42.59 and with a Cronbach alpha reliability of .83. To confirm the obtained factor structure, Phase III was carried out on a sample of three hundred Muslim participants. The results of CFA confirmed the two-dimensional factor structure with a good model fit to the data. Phase IV provided evidence of convergent and discriminant validity of the scale. Moreover, data for validation were collected from an independent sample (N = 204). Finally, the results of validation revealed that there exists a significant positive correlation of Belief in Divine Retribution Scale with Belief in Just World Scale, which provided evidence of convergent validity. However, there exists a non-significant correlation of Belief in Divine Retribution Scale with Religious Practice Subscale of Short Muslim Practice and Belief Scale, and it provided evidence of discriminant validity. Implications along with limitations and suggestions for future research have also been mentioned.

Reliability and validity of the adapted Finnish version of the early onset scoliosis questionnaire (EOSQ-24)

BACKGROUND

EOSQ-24 is a disease specific patient-reported outcome score used to assess the quality of life in patients with early-onset scoliosis. The aim of this study was to translate and cross-culturally adapt the English version of the EOSQ-24 to Finnish language and to assess the reliability and validity of the translation.

METHODS

Cross-cultural adaptation and cross-cultural validation were performed to the Finnish translation of the EOSQ-24. Patients and/or their caretakers were then recruited to assess the psychometric properties of the translation. We assessed the internal consistency, test-retest reliability, floor and ceiling effects, and discriminative abilities. One-hundred-and-three patients filled the questionnaire.

RESULTS

EOSQ-24 was successfully translated into Finnish. The translation showed excellent internal consistency (Cronbach alpha 0.94), satisfactory item-total correlations ranging from 0.6 to 0.9, and moderate to strong inter item correlations. Test-retest reliability ranged from 0.7 to 0.96 indicating good to excellent agreement. Patients with neuromuscular and syndromic scoliosis reported lower EOSQ-24 scores when compared to patients' idiopathic and congenital scoliosis. There was a significant negative correlation between major curve and EOSQ-24 scores in patients with idiopathic early onset scoliosis.

CONCLUSION

The internal consistency and test-retest reliability of the measure were found to be satisfactory. A marked ceiling effect was observed, indicating a potential source of error.

Climbing anxiety scale (CAS-20): Preliminary development and validation

Anxiety has been the primary focus of emotion research in sport psychology. Most of the existing anxiety measures focus on the competition related anxiety. Little is known about the way in which anxiety affects athletic outcomes in extreme sports. We contribute to the literature on anxiety in extreme sports by: (1) developing and providing a preliminary validation for a novel, theoretically anchored sport climbing inventory, Climbing Anxiety Scale (CAS-20), among an international sample of rock-climbers (N = 153); and (2) providing preliminary evidence on its factorial and criterion-related validity. Our investigation includes two phases. The first phase (6 clinical and sport psychology experts) included the development and expert review of a climbing specific anxiety scale. The second phase (N = 153) offers preliminary evidence pertaining to the measure's reliability, factorial, convergent and criterion related validity. Factorial validity was investigated by deploying a series of confirmatory factorial analyses. Convergent and discriminatory validity were examined by comparing the scale's associations with a general anxiety measure, a sport anxiety measure, as well as climbing self-efficacy. Criterion-related validity was estimated by examining its relationship with rock-climbing performance. We contribute to the general domain of sport and athletic research by developing a sport-specific anxiety measure, investigating whether and how anxiety comes into play in rock-climbing, a high-risk sport. This scale can be used for assessing anxiety in climbing and monitoring the impact of an interventions designed to reduce these symptoms.

An Open-Source R Package for Detection of Adverse Events Under-Reporting in Clinical Trials: Implementation and Validation by the IMPALA (Inter coMPany quALity Analytics) Consortium

Accurate and timely reporting of adverse events (AEs) in clinical trials is crucial to ensuring data integrity and patient safety. However, AE under-reporting remains a challenge, often highlighted in Good Clinical Practice (GCP) audits and inspections. Traditional detection methods, such as on-site investigator audits via manual source data verification (SDV), have limitations. Addressing this, the open-source R package {simaerep} was developed to facilitate rapid, comprehensive, and near-real-time detection of AE under-reporting at each clinical trial site. This package leverages patient-level AE and visit data for its analyses. To validate its efficacy, three member companies from the Inter coMPany quALity Analytics (IMPALA) consortium independently assessed the package. Results showed that {simaerep} consistently and effectively identified AE under-reporting across all three companies, particularly when there were significant differences in AE rates between compliant and non-compliant sites. Furthermore, {simaerep}'s detection rates surpassed heuristic methods, and it identified 50% of all detectable sites as early as 25% into the designated study duration. The open-source package can be embedded into audits to enable fast, holistic, and repeatable quality oversight of clinical trials.

External Validation of the OAC3-PAD Bleeding Score in a Nationwide Population of Patients Undergoing Invasive Treatment for Peripheral Arterial Disease

OBJECTIVE

The OAC3-PAD score was developed to predict bleeding risk in patients with lower extremity peripheral arterial disease (PAD), but its performance in concomitant international cohorts is largely unknown. This study aimed to validate the OAC3-PAD score in an unselected nationwide population of patients undergoing invasive treatment for symptomatic PAD.

METHODS

This was a nationwide cohort study including all patients who underwent a first revascularisation procedure or major amputation for symptomatic PAD in Denmark from 2000 - 2021. The study population was stratified based on OAC3-PAD score, and the one year risk of major bleeding was assessed, accounting for the competing risk of death. The score performance was evaluated using calibration plots, C statistic, Brier score, and the index of prediction accuracy (IPA).

RESULTS

A total of 52 016 patients were included (mean age 71 years, 43.8% female). The one year risk of major bleeding increased with higher OAC3-PAD score, ranging from 1.6% (95% confidence interval [CI] 1.4 - 1.8%) to 2.3% (95% CI 2.0 - 2.5%), 3.5% (95% CI 3.2 - 3.8%), and 5.2% (95% CI 4.8 - 5.6%) for patients with low, low moderate, moderate high, and high score, respectively. Using patients with low risk as reference, the OAC3-PAD score effectively categorised patients, demonstrating statistically significant differences in bleeding risk across strata. However, the score showed modest discriminative performance, with a C statistic of 65% (95% CI 63 - 66%) and a Brier score of 2.6% (95% CI 2.5 - 2.7%). Nevertheless, it performed significantly better than the null model, as indicated by an IPA of 3.1%.

CONCLUSION

Among patients who underwent invasive treatment for symptomatic PAD in routine care, the OAC3-PAD score was associated with greater risk of major bleeding with increasing score level. However, its discriminatory ability was modest, and the clinical utility remains to be determined.

Assessing Adolescent Functioning from Different Perspectives: Extending the Validation of the Adolescent Functioning Scale (AFS)

The study aimed to provide further evidence for the validity of the 33-item Adolescent Functioning Scale (AFS) as a parent- and adolescent-report scale of adolescent adjustment. In separate samples of parents (N = 542; 88% female) and adolescents (N = 303; 60% female), confirmatory factor analyses supported the original 4-factor structure of the AFS. Analyses produced a 28-item parent measure, and a 27-item adolescent measure. Parent and adolescent versions included positive development, oppositional behaviour, antisocial behaviour and emotional problems subscales. Evidence for convergent and construct validity was provided through correlations with existing measures of adolescent functioning and parenting. The AFS demonstrated configural and metric invariance, but not scalar variance. The study provided support for the validity and reliability of the revised AFS for parents and adolescents. The strong psychometric properties, and brief and multi-dimensional nature of the AFS means that it will have utility in research and applied contexts.

Leveraging faculty development to support validation of entrustable professional activities assessment tools in anatomic and clinical pathology training

Entrustable professional activities (EPAs) are observable activities that define the practice of medicine and provide a framework of evaluation that has been incorporated into US medical school curricula in both undergraduate and graduate medical education. This manuscript describes the development of an entrustment scale and formative and summative evaluations for pathology EPAs, outlines a process for faculty development that was employed in a pilot study implementing two Anatomic Pathology and two Clinical Pathology EPAs in volunteer pathology residency programs, and provides initial validation data for the proposed pathology entrustment scales. Prior to implementation, faculty development was necessary to train faculty on the entrustment scale for each given activity. A "train the trainer" model used performance dimension training and frame of reference training to train key faculty at each institution. The session utilized vignettes to practice determination of entrustment ratings and development of feedback for trainees as to strengths and weaknesses in the performance of these activities. Validity of the entrustment scale is discussed using the Messick framework, based on concepts of content, response process, and internal structure. This model of entrustment scales, formative and summative assessments, and faculty development can be utilized for any pathology EPA and provides a roadmap for programs to design and implement EPA assessments into pathology residency training.

Societal Attitudes Towards Autism (SATA): Validation of the Greek Version in the General Population

This study examined the validity of the Greek version of the Societal Attitudes Towards Autism (SATA) scale in a Greek community sample (n = 633) and explored how the demographic variables of the sample modulate knowledge and attitudes regarding people with Autism Spectrum Disorder (ASD). The principal component analysis confirmed the three-dimension model and explained 40.5% of the variance. All Cronbach's alpha values obtained were over 0.70. SATA's subscales were significantly and positively correlated, indicating good internal reliability. Participants presented moderate knowledge about ASD and mediocre positive attitudes towards people with ASD. Gender, age, and educational level significantly affected SATA total scores. Overall, this Greek version of SATA showed acceptable psychometric properties, indicating that can be a reliable scale for use.

[Comparison of different prediction models for the occurrence of nausea and vomiting in the postoperative phase : A systematic qualitative comparison based on prospectively defined quality indicators]

BACKGROUND

Various prognostic prediction models exist for evaluating the risk of nausea and vomiting in the postoperative period (PONV). So far, no systematic comparison of these prognostic scores is available.

METHOD

A systematic literature search was carried out in seven medical databases to find publications on prognostic PONV models. Identified scores were assessed against prospectively defined quality criteria, including generalizability, validation and clinical relevance of the models.

RESULTS

The literature search revealed 62 relevant publications with a total of 81,834 patients which could be assigned to 8 prognostic models. The simplified Apfel score performed best, primarily because it was extensively validated. The Van den Bosch score and Sinclair score tied for second place. The simplified Koivuranta score was in third place.

CONCLUSION

The qualitative analysis highlights the strengths and weaknesses of each prediction system based on predetermined standardized quality criteria.

Development and Validation of Case-Finding Algorithms to Identify Pancreatic Cancer in the Veterans Health Administration

BACKGROUND

Survival in pancreatic ductal adenocarcinoma (PDAC) remains poor due to late diagnosis. Electronic Health Records (EHRs) can be used to study this rare disease, but validated algorithms to identify PDAC in the United States EHRs do not currently exist.

AIMS

To develop and validate an algorithm using Veterans Health Administration (VHA) EHR data for the identification of patients with PDAC.

METHODS

We developed two algorithms to identify patients with PDAC in the VHA from 2002 to 2023. The algorithms required diagnosis of exocrine pancreatic cancer in either ≥ 1 or ≥ 2 of the following domains: (i) the VA national cancer registry, (ii) an inpatient encounter, or (iii) an outpatient encounter in an oncology setting. Among individuals identified with ≥ 1 of the above criteria, a random sample of 100 were reviewed by three gastroenterologists to adjudicate PDAC status. We also adjudicated fifty patients not qualifying for either algorithm. These patients died as inpatients and had alkaline phosphatase values within the interquartile range of patients who met ≥ 2 of the above criteria for PDAC. These expert adjudications allowed us to calculate the positive and negative predictive value of the algorithms.

RESULTS

Of 10.8 million individuals, 25,533 met ≥ 1 criteria (PPV 83.0%, kappa statistic 0.93) and 13,693 individuals met ≥ 2 criteria (PPV 95.2%, kappa statistic 1.00). The NPV for PDAC was 100%.

CONCLUSIONS

An algorithm incorporating readily available EHR data elements to identify patients with PDAC achieved excellent PPV and NPV. This algorithm is likely to enable future epidemiologic studies of PDAC.

Translation and validation of the Vietnamese Epilepsy Self-Management Scale (V-ESMS)

OBJECTIVES

This study aimed to translate and validate the Vietnamese version of the Epilepsy Self-Management Scale (V-ESMS).

METHODS

The translation and cross-cultural adaptation of the original version of the ESMS into Vietnamese followed the Principles of Good Practice for the Translation and Cultural Adaptation Process for Patient-Reported Outcomes Measures guideline with "forward-backward" translation and culturally adapted. The participants were recruited consecutively at neurology clinics at Nguyen Tri Phuong Hospital and University Medical Center, Ho Chi Minh City, from January 2022 to July 2022 and required to complete the V-ESMS. The validity was assessed by exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Cronbach's alpha and intraclass correlation coefficient (ICC) were used to evaluate internal and temporal reliability, respectively.

RESULTS

A total of 200 participants were recruited for analysis. The V-ESMS included 36 items and five domains. The factor loading ranged between 0.313 and 0.927; most items loaded in their hypothesized factors proved in the original scale. Using the CFA, theCMIN/DF, comparative fit index, and root mean square error of approximation were 2.883, 0.80, and 0.097, respectively. The Cronbach's alpha in each domain was 0.79-0.907; the scale was 0.936. The ICC from 0.94 to 0.98 showed excellent test-retest reliability.

CONCLUSION

The 36-item V-ESMS with five domains presented good validity and reliability. This instrument could be used to assess self-management in people with epilepsy in Vietnam.

From data to a validated score-based LR system: A practitioner's guide

Likelihood ratios (LRs) are a useful measure of evidential strength. In forensic casework consisting of a flow of cases with essentially the same question and the same analysis method, it is feasible to construct an 'LR system', that is, an automated procedure that has the observations as input and an LR as output. This paper is aimed at practitioners interested in building their own LR systems. It gives an overview of the different steps needed to get to a validated LR system from data. The paper is accompanied by a notebook that illustrates each step with an example using glass data. The notebook introduces open-source software in Python constructed by NFI (Netherlands Forensic Institute) data scientists and statisticians.

Quantification of low-level human cytomegalovirus and Epstein-Barr virus DNAemia by digital PCR

BACKGROUND

Digital PCR (dPCR) can quantify cell-free viral DNA (DNAemia), a biomarker of active viral infection. To accelerate epidemiologic investigation into low-level viral reactivation in chronic disease, we have evaluated the performance of dPCR to detect cytomegalovirus (CMV) and Epstein-Barr virus (EBV) DNAemia across platforms and blood matrices.

METHODS

The droplet-based (BioRad) dPCR platform performance was compared to chip-based (BioMark), and assay validation followed dMIQE guidelines. CMV and EBV DNA reference materials were spiked into known negative plasma and serum samples. In addition, two independent cohorts of ovarian cancer patients were evaluated for viral DNAemia (n = 65 serum and 79 plasma samples).

RESULTS

The limit of quantification (LOQ) was at or slightly above 100 copies/mL for both instruments: 105-135 copies/mL for droplet-based detection and 100 copies/mL for chip-based detection. DNAemia in serum had a slightly lower LOQ (105-110 copies/mL) compared to plasma (LOQ; 115-135 copies/mL). The variation (CV) coefficients for each assay and machine were less than 5 %. In patient samples, CVs ranged from 4.5 - 7.4 % and were similar for cell-free DNA derived from serum or plasma. There was good correlation between DNAemia measurements in patient samples across dPCR platforms (r > 0.90 for each assay and matrix).

CONCLUSION

dPCR can quantify low-level herpes virus DNAemia with CVs below 8 %. Our results indicate that using serum-derived cell-free DNA and droplet-based dPCR is optimal for quantitating low-level viral DNAemia; however, plasma and chip-based approaches are acceptable alternatives and suitable for epidemiologic investigation.