Expected impact of MRI-targeted biopsy interreader variability among uropathologists on ProScreen prostate cancer screening trial: a pre-trial validation study

PURPOSE

Prostate cancer (PCa) histology, particularly the Gleason score, is an independent prognostic predictor in PCa. Little is known about the inter-reader variability in grading of targeted prostate biopsy based on magnetic resonance imaging (MRI). The aim of this study was to assess inter-reader variability in Gleason grading of MRI-targeted biopsy among uropathologists and its potential impact on a population-based randomized PCa screening trial (ProScreen).

METHODS

From June 2014 to May 2018, 100 men with clinically suspected PCa were retrospectively selected. All men underwent prostate MRI and 86 underwent targeted prostate of the prostate. Six pathologists individually reviewed the pathology slides of the prostate biopsies. The five-tier ISUP (The International Society of Urological Pathology) grade grouping (GG) system was used. Fleiss' weighted kappa (κ) and Model-based kappa for associations were computed to estimate the combined agreement between individual pathologists.

RESULTS

GG reporting of targeted prostate was highly consistent among the trial pathologists. Inter-reader agreement for cancer (GG1-5) vs. benign was excellent (Model-based kappa 0.90, Fleiss' kappa κ = 0.90) and for clinically significant prostate cancer (csPCa) (GG2-5 vs. GG0 vs. GG1), it was good (Model-based kappa 0.70, Fleiss' kappa κ 0.67).

CONCLUSIONS

Inter-reader agreement in grading of MRI-targeted biopsy was good to excellent, while it was fair to moderate for MRI in the same cohort, as previously shown. Importantly, there was wide consensus by pathologists in assigning the contemporary GG on MRI-targeted biopsy suggesting high reproducibility of pathology reporting in the ProScreen trial.

Co-targeting the kappa opioid receptor and dopamine transporter reduces motivation to self-administer cocaine and partially reverses dopamine system dysregulation

Cocaine disrupts dopamine (DA) and kappa opioid receptor (KOR) system activity, with long-term exposure reducing inhibiton of DA uptake by cocaine and increasing KOR system function. Single treatment therapies have not been successful for cocaine use disorder; therefore, this study focuses on a combination therapy targeting the dopamine transporter (DAT) and KOR. Sprague Dawley rats self-administered 5 days of cocaine (1.5 mg/kg/inf, max 40 inf/day, FR1), followed by 14 days on a progressive ratio (PR) schedule (0.19 mg/kg/infusion). Behavioral effects of individual and combined administration of phenmetrazine and nBNI were then examined using PR. Additionally, ex vivo fast scan cyclic voltammetry was then used to assess alterations in DA and KOR system activity in the nucleus accumbens before and after treatments. Chronic administration of phenmetrazine as well as the combination of phenmetrazine and nBNI-but not nBNI alone-significantly reduced PR breakpoints. In addition, the combination of phenmetrazine and nBNI partially reversed cocaine-induced neurodysregulations of the KOR and DA systems, indicating therapeutic benefits of targeting the DA and KOR systems in tandem. These data highlight the potential benefits of the DAT and KOR as dual-cellular targets to reduce motivation to administer cocaine and reverse cocaine-induced alterations of the DA system.

Calvarial multiple myeloma: Raindrop skull

Background

The "Raindrop skull" appearance represents the multiple punched-out and lytic lesions hitting a surface and creating a scattered splash pattern.

Case Description

A 73-year-old female presented with multiple painless lumps over the forehead and head. The patient reported unintentional weight loss, fatigability, loss of appetite, fever, night sweats, and back pain for seven months (B symptoms). The examination revealed multiple, nonmobile, calvarial lesions with defined borders, measuring approximately 1 × 1 cm. Laboratory investigations of serum-free light chains showed a free kappa level of 12.91 mg/L, a lambda level of 4549.28 mg/L, and a free kappa/lambda ratio of 0.00. Radiological imaging of the skull and brain showed a "raindrop skull" appearance and multiple calvarial osteolytic lesions. The patient underwent a right superior iliac crest bone marrow aspirate and trephine biopsy. The laboratory and histopathological sections were compatible with multiple myeloma. A diagnosis of multiple myeloma (free light chain lambda) was rendered.

Conclusion

Calvarial multiple myeloma is rare and requires a high index of suspicion to diagnose. "Raindrop skull" appearance is pathognomonic of calvarial multiple myeloma.

Does coding internal working models of attachment have to be so hard?

The Child Attachment Interview (CAI) has demonstrated promise in youth, yet widespread use is thwarted by the need for interview transcription, face-to-face training, and reliability certification. The present study sought to examine the empirical basis for these barriers. Thirty-five archival CAIs were re-coded by: (1) expert coders (i.e., trained and reliable) without access to transcripts, (2) trained coders who had not completed reliability training, and (3) novice coders who had no formal training. Agreement with consensus classifications was computed with the expectation of moderate agreement. Results supported coding by experts without transcription of the interview. Near-moderate agreement preliminarily supported the use of trained coders who have not attempted reliability certification with appropriate caveats. While moderate agreement was not achieved for novice raters, findings suggest that self-paced training options for the CAI may hold future promise. These contributions erode a number of significant barriers to the current use of the CAI.

IUPHAR themed review: Opioid efficacy, bias, and selectivity

Drugs acting at the opioid receptor family are clinically used to treat chronic and acute pain, though they represent the second line of treatment behind GABA analogs, antidepressants and SSRI's. Within the opioid family mu and kappa opioid receptor are commonly targeted. However, activation of the mu opioid receptor has side effects of constipation, tolerance, dependence, euphoria, and respiratory depression; activation of the kappa opioid receptor leads to dysphoria and sedation. The side effects of mu opioid receptor activation have led to mu receptor drugs being widely abused with great overdose risk. For these reasons, newer safer opioid analgesics are in high demand. For many years a focus within the opioid field was finding drugs that activated the G protein pathway at mu opioid receptor, without activating the β-arrestin pathway, known as biased agonism. Recent advances have shown that this may not be the way forward to develop safer analgesics at mu opioid receptor, though there is still some promise at the kappa opioid receptor. Here we discuss recent novel approaches to develop safer opioid drugs including efficacy vs bias and fine-tuning receptor activation by targeting sub-pockets in the orthosteric site, we explore recent works on the structural basis of bias, and we put forward the suggestion that Gα subtype selectivity may be an exciting new area of interest.

Kappa opioid agonists in the treatment of itch: just scratching the surface?

Chronic pruritus is a debilitating condition affecting 23-44 million Americans. Recently, kappa opioid agonists (KOAs) have emerged as a novel class of potent antipruritic agents. In 2021, the Food and Drug Administration approved difelikefalin (Korsuva) for the treatment of moderate-to-severe pruritus associated with chronic kidney disease in adults undergoing hemodialysis. Difelikefalin is a potent, peripherally restricted KOA that is intravenously available. Although promising, difelikefalin is currently available as an intravenous composition only, limiting the scope of use. Oral formulations of difelikefalin did not meet the primary endpoint criteria in recent phase 2 clinical trials; however, additional clinical studies are ongoing. The future for KOAs in the treatment of pruritus is encouraging. Orally active pathway-biased KOAs, such as triazole 1.1, may serve as viable alternatives with broader applications. Extended-release compositions, such as the TP-2021 ProNeura subdermal implant, may circumvent the pharmacokinetic issues associated with peptide-based KOAs. Lastly, dual-acting kappa opioid receptor agonist/mu opioid receptor antagonists are orally bioavailable and may be useful in the treatment of various forms of chronic itch. In this review, we summarize the results of KOAs in clinical and preclinical trials and discuss future directions of drug development.

Influence of a multifocal intraocular lens centration and eye angles on light distortion and ocular scatter index

PURPOSE

To assess how eye axes and multifocal intraocular lens (MIOL) centration may impact the light distortion index (LDI) and ocular scatter index (OSI).

METHODS

Fifty-eight subjects implanted with the trifocal MIOL Q-Flex M 640PM or Liberty 677MY (Medicontur) were included in this retrospective analysis. The following variables were collected with the Pentacam Wave (Oculus) considering the vertex normal as the coordinates center: chord-mu to the center of the pupil, chord-alpha to the geometrical center of the cornea, and chord-MIOL to the center of the diffractive ring. These measurements were correlated with OSI (HD Analyzer, Visiometrics) and LDI (light distortion analyzer, CEORLab).

RESULTS

Chord-MIOL centroid was 0.12 mm at 62°, chord-mu was 0.09 mm at 174°, and chord-alpha was 0.38 mm at 188°. A relationship was found between OSI and LDI, rho = 0.58, p < 0.0005). No relationships were found between chord-mu or chord-alpha and the LDI or OSI, neither for the total magnitude, nor the decomposition in orthogonal components (p > 0.05). The LDI was significantly correlated with the temporal centration of the MIOL versus the vertex normal (rho = 0.32, p = 0.02).

CONCLUSIONS

As opposed to what has been previously described, the temporal centration of the MIOL was related to a decrease in the LDI. Future studies with extreme values of the included variables are required to establish cut-offs for considering these variables as exclusion criteria in the implantation of a MIOL.

KappaAcc: A program for assessing the adequacy of kappa

Categorical cutpoints used to assess the adequacy of various statistics-like small, medium, and large for correlation coefficients of .10, .30, and .50 (Cohen, Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Lawrence Erlbaum Associates.)-are as useful as they are arbitrary, but not all statistics are suitable candidates for categorical cutpoints. One such is kappa, a statistic that gauges inter-observer agreement corrected for chance (Cohen Educational and Psychological Measurement, 20(1), 37-46, Cohen, Educational and Psychological Measurement 20:37-46, 1960). Depending on circumstances, a specific value of kappa may be judged adequate in one case but not in another. Thus, no one value of kappa can be regarded as universally acceptable and the question for investigators should be, are observers accurate enough, not is kappa big enough. A principled way to assess whether a specific value of kappa is adequate is to estimate observer accuracy-how accurate would simulated observers need to be to have generated a specific value of kappa obtained by actual observers, given specific circumstances. Estimating observer accuracy based on a kappa table the user provides is what KappaAcc, the program described here, does.

Inter- and intra-observer agreement in the assessment of the cervical transformation zone (TZ) by visual inspection with acetic acid (VIA) and its implications for a screen and treat approach: a reliability study

BACKGROUND

In low-resource countries, interpretation of the transformation zone (TZ) using the classification of the International Federation for Cervical Pathology and Colposcopy (IFCPC), adopted by the World Health Organization, is critical for determining if visual inspection with acetic acid (VIA) screening and thermal ablation treatment are possible. We aim to assess inter- and intra-observer agreement in TZ interpretation.

METHODS

We performed a prospective multi-observer reliability study. One hundred cervical digital images of Human papillomavirus positive women (30-49 years) were consecutively selected from a Cameroonian cervical cancer screening trial. Images of the native cervix and after VIA were obtained. The images were evaluated for the TZ type at two time points (rounds one and two) by five VIA experts from four countries (Côte d'Ivoire, Cameroon, Peru, and Zambia) according to the IFCPC classification (TZ1 = ectocervical fully visible; TZ2 = endocervical fully visible; TZ3 = not fully visible). Intra- and inter-observer agreement were measured by Fleiss' kappa.

RESULTS

Overall, 37.0% of images were interpreted as TZ1, 36.4% as TZ2, and 26.6% as TZ3. Global inter-observer reliability indicated fair agreement in both rounds (kappa 0.313 and 0.288). The inter-observer agreement was moderate for TZ1 interpretation (0.460), slight for TZ2 (0.153), and fair for TZ3 (0.329). Intra-observer analysis showed fair agreement for two observers (0.356 and 0.345), moderate agreement for two other (0.562 and 0.549), and one with substantial agreement (0.728).

CONCLUSION

Interpretation of the TZ using the IFCPC classification, adopted by the World Health Organization, is critical for determining if VIA screening and thermal ablation treatment are possible. However, the low inter- and intra-observer agreement suggest that the reliability of the referred classification is limited in the context of VIA. It's integration in treatment recommendations should be used with caution since TZ3 interpretation could lead to an important referral rate for further evaluation. Trial registration Cantonal Ethics Board of Geneva, Switzerland: N°2017-0110. Cameroonian National Ethics Committee for Human Health Research N°2018/07/1083/CE/CNERSH/SP.

Accuracy of determination of free light chains (Kappa and Lambda) in plasma and serum by Swedish laboratories as monitored by external quality assessment

BACKGROUND

Free light chain (FLC) measurements are important in diagnosing monoclonal gammopathies. As FLC are heterogeneous, different reagents and instruments for measuring FLC concentrations may give diverging results that affect assessment of patients with monoclonal gammopathies. Here we investigated agreement between different FLC methods using data from the Swedish external quality assurance (EQA) programme.

METHODS

The two main FLC assays, N Latex FLC (Siemens) and Serum Freelite (The Binding Site), using four nephelometric or turbidimetric instrument platforms, were compared. Results from 27 EQA rounds distributed to 11-16 Swedish hospital laboratories during 2015-2020 were investigated.

RESULTS

The kappa (κ) FLC measurements deviated significantly over time, but when only nephelometry was used, deviation from the mean was lower (median ranges: -5% to 13 %). The CV was significantly higher for the Freelite assay (mean CV = 8.7) than for the N latex assay (mean CV = 5.7) (p < 0.0001). The coefficient of determination between all combinations of reagents and instrument platforms used was generally good (r² = 0.76-0.87), and the correlation slope acceptable (0.81-1.2). For lambda (λ) FLC measurements, no concordance between combinations of instruments and reagents is apparent, deviating between -40 % to + 48 % from the mean. The CV was significantly higher for the combination with nephelometry and the Freelite assay (CV mean = 13.9 %) than nephelometry and the N latex assay (CV mean = 9.9 %) (p <0.001). The coefficient of determination varied between combinations of reagents and instrument platforms (r² = 0.59-0.89) and the slope ranged between 0.48 and 1.5. Significant differences between the two reagents used were sometimes noted.

CONCLUSIONS

Imprecision in λFLC affects the κFLC/λFLC ratio. This may be important in clinical assessment of patients, especially differentiating between monoclonal and polyclonal gammopathies.

Differentiation of SARS-CoV-2 Variants Using RT-qPCRs by Targeting Recurrent Mutation Sites: A Diagnostic Laboratory Experience from Multi-Center Regional Study, August 2020-December 2021, Poland

Rapid identification of SARS-CoV-2 variants is essential for epidemiological surveillance. RT-qPCR-based variant differentiation tests can be used to quickly screen large sets of samples for relevant variants of concern/interest; this study was conducted on specimens collected at 11 centers located in Poland during routine SARS-CoV-2 diagnostics between August 2020 and December 2021. A total of 1096 samples (with CT < 30) were screened for Alpha, Beta, Delta, Kappa and Omicron variants using commercial assays targeting repeat mutation sites. Variants were assigned to 434 (39.6%) specimens; the remaining 662 (60.4%) samples were not classified (no tested mutations detected). Alpha (n = 289; 66.59%), Delta (n = 115; 26.5%), Kappa (n = 30; 6.91%) and Omicron (n = 2; 0.46%) variants were identified and their distribution changed over time. The first Alpha variant appeared in October 2020, and it began to gradually increase its proportion of the virus population by June 2021. In July 2021, it was replaced by the Delta variant, which already dominated by the end of the year. The first Kappa was detected in October 2021, while Omicron was found in December 2021. The screening of samples allowed the determination of epidemiological trends over a time interval reflecting the national COVID-19 waves.

Tau and kappa in interception - how perceptual spatiotemporal interrelations affect movements

Batting and catching are real-life examples of interception. Due to latencies between the processing of sensory input and the corresponding motor response, successful interception requires accurate spatiotemporal prediction. However, spatiotemporal predictions can be subject to bias. For instance, the more spatially distant two sequentially presented objects are, the longer the interval between their presentations is perceived (kappa effect) and vice versa (tau effect). In this study, we deployed these phenomena to test in two sensory modalities whether temporal representations depend asymmetrically on spatial representations, or whether both are symmetrically interrelated. We adapted the tau and kappa paradigms to an interception task by presenting four stimuli (visually or auditorily) one after another on four locations, from left to right, with constant spatial and temporal intervals in between. In two experiments, participants were asked to touch the screen where and when they predicted a fifth stimulus to appear. In Exp. 2, additional predictive gaze measures were examined. Across experiments, auditory but not visual stimuli produced a tau effect for interception, supporting the idea that the relationship between space and time is moderated by the sensory modality. Results did not reveal classical auditory or visual kappa effects and no visual tau effects. Gaze data in Exp. 2 showed that the (spatial) gaze orientation depended on temporal intervals while the timing of fixations was modulated by spatial intervals, thereby indicating tau and kappa effects across modalities. Together, the results suggest that sensory modality plays an important role in spatiotemporal predictions in interception.

SARS-CoV-2 Kappa Variant Shows Pathogenicity in a Syrian Hamster Model

Objectives: The emergence of SARS-CoV-2 lineage B.1.617 variants in India has been associated with a surge in the number of daily infections. We investigated the pathogenic potential of Kappa (B.1.617.1) variant in Syrian golden hamsters. Methods: Two groups of Syrian golden hamsters (18 each) were inoculated intranasally with SARS-CoV-2 isolates, B.1 (D614G) and Kappa variant, respectively. The animals were monitored daily for the clinical signs and body weight. Throat swab, nasal wash, and organ samples (lungs, nasal turbinate, trachea) were collected and screened using SARS-CoV-2-specific RT-qPCR. Histopathologic evaluation of the lung samples was performed. Results: The hamsters infected with the Kappa variant demonstrated increased body weight loss compared to the B.1 lineage isolate. The highest viral RNA load was observed in the nasal turbinate and lung specimens of animals infected with both variants. A significantly higher sgRNA load was observed in the nasal swabs (7 DPI), trachea (3 DPI), and lungs (3 DPI) of hamsters infected with the Kappa variant. Neutralizing antibody response generated in the B.1 lineage-infected hamster sera were comparable against both B.1 and Kappa variant in contrast to Kappa variant-infected hamsters, which showed lower titers against B.1 lineage isolate. Gross and microscopic evaluation of the lung specimens showed severe lung lesions in hamsters infected with Kappa variant compared to B.1. Conclusions: The study demonstrates pathogenicity of Kappa variant in hamsters evident with reduced body weight, high viral RNA load in lungs, and pronounced lung lesions. Both Kappa variant- and B.1-infected hamsters produced neutralizing antibodies against both variants studied.

Prevalence of intestinal parasites in dogs in southern Ontario, Canada, based on fecal samples tested using sucrose double centrifugation and Fecal Dx® tests

In southern Ontario, Canada, there is a lack of information concerning the prevalence of intestinal parasites in dogs. As such, this study aimed to characterize the prevalence of intestinal parasites in dogs visiting off-leash parks in the region using sucrose double centrifugation and Fecal Dx® tests. Additionally, data obtained via the sucrose double centrifugation method were used to evaluate the performance of the Fecal Dx® tests. Fecal samples were collected from 466 dogs aged ≥6 months from May to November 2018 (mean age = 3.7 years). Overall, eleven intestinal parasites were identified using sucrose double centrifugation. Roundworm eggs (Toxocara canis and Baylisascaris procyonis), hookworm eggs (Ancylostoma caninum and Uncinaria stenocephala), and whipworm eggs (Trichuris vulpis) were identified in 1.07% (95% confidence interval [CI] 0.38-2.56%), 5.79% (95% CI 3.85-8.31%), and 5.15% (95% CI 3.33-7.57) of samples, respectively. Using the Fecal Dx® tests, 1.07% (95% CI 0.38-2.56%), 4.29% (95% CI 2.64-6.55%), and 2.15% (95% CI 1.03-3.91) of the samples tested positive for roundworm, hookworm, and whipworm antigen, respectively. To assess the level of agreement between the Fecal Dx® tests and sucrose double centrifugation, three methods were used. Cohen's kappa indicated a fair-to-moderate level of agreement between Fecal Dx® tests and sucrose double centrifugation. In contrast, the prevalence-adjusted bias-adjusted kappa and Gwet's first-order agreement coefficient indicated almost perfect agreement between these tests, ranging from 0.87 to 0.99 among the parasites examined. This study provides valuable information on the prevalence of intestinal parasites in mature dogs in southern Ontario that will help guide parasite control recommendations for dogs in this region.

Interclinician agreement on the recognition of selected respiratory clinical signs in dogs and cats with abnormal breathing patterns

In humans, classification of abnormal breathing patterns (ABP) and recognition of ancillary respiratory signs are difficult, as reflected by poor-to-moderate interclinician agreement. The aims of this study were to assess interclinician agreement for respiratory sign recognition in dogs and cats and evaluate the influence of clinical experience on agreement. Dogs and cats with ABP were recruited from three hospitals. Included animals were evaluated by three clinicians at each hospital before therapeutic intervention. Consensual definitions for each respiratory clinical sign were provided to all clinicians. Interclinician agreement was measured via Fleiss' kappa and intraclass correlation coefficient statistics. Influence of clinical experience on interobserver agreement was studied via mixed-effects logistic regression. One-hundred and fifteen dogs and 49 cats with ABP were recruited. Out of 12 clinical signs evaluated, only stertor (kappa, 0.80), stridor (kappa, 0.64), attenuation of heart/lung sounds (kappa, 0.60), and goose honking (kappa, 0.84) in dogs, and stertor (kappa, 0.65) and open-mouth breathing (kappa, 0.75) in cats, were considered sufficiently reliable among clinicians. Agreement on respiratory rate estimation was good in both species (intraclass correlation coefficient, 0.75). The greater the difference in clinical experience between two clinicians, the lower the odds of agreement between the two clinicians' respiratory physical examination findings. Interclinician agreement was demonstrated to be poor for recognition of most respiratory clinical signs in dogs and cats. Teaching and clinical experience acquisition should be encouraged to improve respiratory clinical sign recognition.

Influence of fellow eye on the diagnosis and classification of central serous chorioretinopathy

PURPOSE

To assess the influence of fellow eye information on diagnosis and classification of central serous chorioretinopathy (CSCR) using multimodal imaging-based classification.

METHODS

This was a retrospective, observational study including patients with CSCR with unilateral or bilateral involvement. Multimodal images of both eyes of each patient were compiled and presented to two masked retina specialists subdivided into three groups: (1) both eye data, (2) right eye data and (3) left eye data. The masked observers graded the CSCR as per the new CSCR classification into simple and complex CSCR in three different scenarios as subdivided above. Interobserver and intraobserver agreement was assessed using Cohen's kappa (95% confidence intervals).

RESULTS

A total of 206 eyes of 103 patients with unilateral or bilateral CSCR were graded. We found a "strong" intraobserver and interobserver agreement when one eye versus both eye data was provided in terms of "simple CSCR" or "complex CSCR" (kappa value = 0.77 and 0.87, p < 0.001, and kappa value = 0.85 and 0.76, p < 0.001, respectively). Forty-three eyes (10.55%) showed discrepancy in classification between observers for individual eyes, whereas only 13 eyes (6.53%) showed discrepancy between observers when both eye data was provided.

CONCLUSION

We conclude that fellow eye information was helpful in solving diagnostic dilemmas and reached 85% consensus in the diagnosis of CSCR between the observers. We found that information of fellow eyes led to a discrepancy only in 6.53% cases with 2.42% cases that had a controversial diagnosis of CSCR. Multimodal imaging-based CSCR classification provides objective approach to diagnose and classify CSCR.

The Conundrum of Kappa and Why Some Musculoskeletal Tests Appear Unreliable Despite High Agreement: A Comparison of Cohen Kappa and Gwet AC to Assess Observer Agreement When Using Nominal and Ordinal Data

In clinical practice, physical therapists often use different kinds of tests and measures in the assessment of their patients. For therapists to have confidence when using their tests and measures, an important attribute is having intratester and intertester reliability. Studies that assess reliability are cases of observer agreement. Many studies have been performed assessing observer agreement in the physical therapy literature. The most commonly used method to assess observer agreement studies that use nominal or ordinal data is the statistical method suggested by Cohen and the corresponding reliability coefficient, Cohen kappa. Recently, Cohen kappa has undergone scrutiny because of what is called kappa paradox, which occurs when observer agreement is high but the resulting kappa value is low. Another paradox also occurs when asymmetries exist between raters on their disagreements, resulting in a higher kappa value. In the physical therapy literature, there are numerous examples of this problem, which can often lead to misunderstanding the meaning of the data. This Perspective examines how and why these problems occur and suggests an alternative method for assessing observer agreement.

[Application of Coefficient for Evaluating Agreement in disordered multi-classification data]

OBJECTIVE

To assess the performance of the Coefficient for Evaluating Agreement (CEA) established based on AC1 coefficient in evaluating the consistency between two raters for disordered multi- classification outcome data in comparison with the Kappa coefficient.

METHODS

The diagnostic test data generated by random sampling and Monte Carlo simulation were used for resampling with different parameter combinations (including sample size, proportion of specified events in the population, accidental evaluation rate and number of categories) to compare the mean square error, variance, and variance of the mean of Kappa, AC1 and CEA. The distribution description of CEA was obtained by random sampling for 1000 times from the population.

RESULTS

The inconsistency of the incidental evaluation rate caused substantial fluctuation of the mean square error of CEA. Compared with the Kappa coefficient, AC1 and CEA was more stable when the population contained extreme proportions of the specified events. For small samples and inconsistent evaluation rates by chance, the variance and the expectation of variance became obviously expanded for Kappa coefficient and showed smaller changes for CEA. CEA showed nearly a normal distribution for a large sample size.

CONCLUSION

Kappa, AC1 and CEA are all the most strongly affected by the accidental evaluation rate, followed then by sample size. For disordered multi-classification outcome data, CEA is more robust against the variations of sample size and accidental evaluation rate.

Antibody-Mediated Neutralization of Authentic SARS-CoV-2 B.1.617 Variants Harboring L452R and T478K/E484Q

The capacity of convalescent and vaccine-elicited sera and monoclonal antibodies (mAb) to neutralize SARS-CoV-2 variants is currently of high relevance to assess the protection against infections. We performed a cell culture-based neutralization assay focusing on authentic SARS-CoV-2 variants B.1.617.1 (Kappa), B.1.617.2 (Delta), B.1.427/B.1.429 (Epsilon), all harboring the spike substitution L452R. We found that authentic SARS-CoV-2 variants harboring L452R had reduced susceptibility to convalescent and vaccine-elicited sera and mAbs. Compared to B.1, Kappa and Delta showed a reduced neutralization by convalescent sera by a factor of 8.00 and 5.33, respectively, which constitutes a 2-fold greater reduction when compared to Epsilon. BNT2b2 and mRNA1273 vaccine-elicited sera were less effective against Kappa, Delta, and Epsilon compared to B.1. No difference was observed between Kappa and Delta towards vaccine-elicited sera, whereas convalescent sera were 1.51-fold less effective against Delta, respectively. Both B.1.617 variants Kappa (+E484Q) and Delta (+T478K) were less susceptible to either casirivimab or imdevimab. In conclusion, in contrast to the parallel circulating Kappa variant, the neutralization efficiency of convalescent and vaccine-elicited sera against Delta was moderately reduced. Delta was resistant to imdevimab, which, however, might be circumvented by combination therapy with casirivimab together.

Antibody-Mediated Neutralization of Authentic SARS-CoV-2 B.1.617 Variants Harboring L452R and T478K/E484Q

The capacity of convalescent and vaccine-elicited sera and monoclonal antibodies (mAb) to neutralize SARS-CoV-2 variants is currently of high relevance to assess the protection against infections. We performed a cell culture-based neutralization assay focusing on authentic SARS-CoV-2 variants B.1.617.1 (Kappa), B.1.617.2 (Delta), B.1.427/B.1.429 (Epsilon), all harboring the spike substitution L452R. We found that authentic SARS-CoV-2 variants harboring L452R had reduced susceptibility to convalescent and vaccine-elicited sera and mAbs. Compared to B.1, Kappa and Delta showed a reduced neutralization by convalescent sera by a factor of 8.00 and 5.33, respectively, which constitutes a 2-fold greater reduction when compared to Epsilon. BNT2b2 and mRNA1273 vaccine-elicited sera were less effective against Kappa, Delta, and Epsilon compared to B.1. No difference was observed between Kappa and Delta towards vaccine-elicited sera, whereas convalescent sera were 1.51-fold less effective against Delta, respectively. Both B.1.617 variants Kappa (+E484Q) and Delta (+T478K) were less susceptible to either casirivimab or imdevimab. In conclusion, in contrast to the parallel circulating Kappa variant, the neutralization efficiency of convalescent and vaccine-elicited sera against Delta was moderately reduced. Delta was resistant to imdevimab, which, however, might be circumvented by combination therapy with casirivimab together.

Interactive effects of (±)-trans-U50488 and its stereoisomers with cannabinoids

The adverse effects of mu opioid agonists have spurred a renewed interest in using kappa opioid receptor (KOR) agonists as analgesics. KOR agonists also have potential for development as diuretics for the treatment of edema and hypertension. Here, we evaluated the discriminative stimulus, antinociceptive, and diuretic effects of the kappa agonist (±)-trans-U-50488 and its stereoisomers (-)-(1S,2S)-U-50488 or (+)-(1R,2R)-U-50488) alone and in combination with the cannabinoid agonist (-)-CP 55,940. To establish (±)-U-50488 as a discriminative stimulus, rats (n = 12) were trained to discriminate intraperitoneal (i.p.) administration of 5.6 mg/kg of (±)-trans-U-50488 from saline under a fixed-ratio 20 (FR-20) schedule of food reinforcement. Then, antinociception was assessed using two procedures: warm water tail withdrawal and von Frey paw withdrawal. Diuretic effects were assessed in separate rats (n = 6/group). Doses of (±)-U-50488 and (-)-U-50488 that served as discriminative stimuli produced significant increases in urine output, but at lower doses than those that produced antinociception. In contrast, (+)-U-50488 alone had no discriminative stimulus or diuretic effects at the doses tested, but did produce antinociception in the von Frey assay. When three cannabinoids and morphine were tested in the (±)-U-50488 discrimination procedure to determine the similarity of these drugs' discriminative stimulus effects to those for (±)-U-50488, the rank order similarity was (-)-CP 55,940 > (-)-trans-THC > (+)-WIN 55,212-2 ≥ morphine. (-)-CP 55,940 alone (0.056 mg/kg) partially substituted for the discriminative stimulus effects of (±)-U-50488 and produced significant diuretic and antinociceptive effects. (-)-CP 55,940 in combination with (±)-U-50488 also produced a two-fold leftward shift in the discriminative stimulus curve for (±)-U-50488, and near-additive antinociception with (±)-U-50488 and (+)-U-50488. Further, the diuretic effect of (-)-CP 55,940 was enhanced by a dose of (+)-U50488, which itself did not alter urine output. These data together indicate that a combination of cannabinoid and kappa opioid agonists can enhance diuresis, but may have limited potential for serving as opioid-sparing pharmacotherapeutics for treatment of pain.

Visual assessment of movement quality: a study on intra- and interrater reliability of a multi-segmental single leg squat test

Background

The Single Leg Squat test (SLS) is a common tool used in clinical examination to set and evaluate rehabilitation goals, but there is not one established SLS test used in the clinic. Based on previous scientific findings on the reliability of the SLS test and with a methodological rigorous setup, the aim of the present study was to investigate the intra- and interrater reliability of a standardised multi-segmental SLS test.

Methods

We performed a study of measurement properties to investigate the intra- and interrater reliability of a standardised multi-segmental SLS test including the assessment of the foot, knee, pelvis, and trunk. Novice and experienced physiotherapists rated 65 video recorded SLS tests from 34 test persons. We followed the Quality Appraisal for Reliability Studies checklist.

Results

Regardless of the raters experience, the interrater reliability varied between “moderate” for the knee variable (ĸ = 0.41, 95% CI 0.10–0.72) and “almost perfect” for the foot (ĸ = 1.00, 95% CI 1.00–1.00). The intrarater reliability varied between “slight” (pelvic variable; ĸ = 0.17, 95% CI -0.22-0.55) to “almost perfect” (foot variable; ĸ = 1.00, 95% CI 1.00–1.00; trunk variable; ĸ = 0.82, 95% CI 0.66–0.97). A generalised kappa coefficient including the values from all raters and segments reached “moderate” interrater reliability (ĸ = 0.52, 95% CI 0.43–0.61), the corresponding value for the intrarater reliability reached “almost perfect” (ĸ = 0.82, 95% CI 0.77–0.86).

Conclusions

The present study shows a “moderate” interrater reliability and an “almost perfect” intrarater reliability for the variable all segments regardless of the raters experience. Thus, we conclude that the proposed standardised multi-segmental SLS test is reliable enough to be used in an active population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13102-021-00289-x.

Effects of kappa opioid receptor agonists on fentanyl vs. food choice in male and female rats: contingent vs. non-contingent administration

RATIONALE

Strategies are needed to decrease the abuse liability of mu opioid receptor (MOR) agonists. One strategy under consideration is to combine MOR agonists with kappa opioid receptor (KOR) agonists.

OBJECTIVES

The effects of KOR agonists (U50488, nalfurafine) on fentanyl-vs.-food choice were compared under conditions where the KOR agonists were added to the intravenously self-administered fentanyl (contingent delivery) or administered as subcutaneous pretreatments (non-contingent delivery) in male and female rats.

METHODS

Rats were trained to respond under a concurrent schedule of fentanyl (0, 0.32-10 μg/kg/infusion) and food reinforcement. In experiment 1, U50488 and nalfurafine were co-administered with fentanyl as fixed-proportion mixtures (contingent administration). In experiment 2, U50488 (1-10 mg/kg) and nalfurafine (3.2-32 μg/kg) were administered as acute pretreatments (non-contingent administration). The selective KOR antagonist, nor-BNI (32 mg/kg), was administered prior to contingent and non-contingent KOR-agonist treatment in experiment 3.

RESULTS

Both U50488 and nalfurafine decreased fentanyl choice when administered contingently, demonstrating that KOR agonists punish opioid choice. However, evidence for punishment corresponded with an elimination of operant responding in the majority of rats. Non-contingent U50488 and nalfurafine administration only decreased the number of choices made during the behavioral session without altering fentanyl choice. Contingent and non-contingent KOR-agonist effects on fentanyl choice were both attenuated by nor-BNI.

CONCLUSIONS

These results illustrate that the effects of KOR agonists on fentanyl reinforcement are dependent upon the contingencies under which they are administered.

Concurrent and discriminant validity of ActiGraph waist and wrist cut-points to measure sedentary behaviour, activity level, and posture in office work

Background

Sedentary Behaviour (SB) gets an increasing attention from ergonomics and public health due to its associated detrimental health effects. A large number of studies record SB with ActiGraph counts-per-minute cut-points, but we still lack valid information about what the cut-points tell us about office work. This study therefore analysed the concurrent and discriminant validity of commonly used cut-points to measure SB, activity level, and posture.

Methods

Thirty office workers completed four office tasks at three workplaces (conventional chair, activity-promoting chair, and standing desk) while wearing two ActiGraphs (waist and wrist). Indirect calorimetry and prescribed posture served as reference criteria. Generalized Estimation Equations analysed workplace and task effects on the activity level and counts-per-minute, and kappa statistics and ROC curves analysed the cut-point validity.

Results

The activity-promoting chair (p < 0.001, ES ≥ 0.66) but not the standing desk (p = 1.0) increased the activity level, and both these workplaces increased the waist (p ≤ 0.003, ES ≥ 0.63) but not the wrist counts-per-minute (p = 0.74) compared to the conventional chair. The concurrent and discriminant validity was higher for activity level (kappa: 0.52–0.56 and 0.38–0.45, respectively) than for SB and posture (kappa ≤0.35 and ≤ 0.19, respectively). Furthermore, the discriminant validity for activity level was higher for task effects (kappa: 0.42–0.48) than for workplace effects (0.13–0.24).

Conclusions

ActiGraph counts-per-minute for waist and wrist placement were – independently of the chosen cut-point – a measure for activity level and not for SB or posture, and the cut-points performed better to detect task effects than workplace effects. Waist cut-points were most valid to measure the activity level in conventional seated office work, but they showed severe limitations for sit-stand desks. None of the placements was valid to detect the increased activity on the activity-promoting chair. Caution should therefore be paid when analysing the effect of workplace interventions on activity level with ActiGraph waist and wrist cut-points.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10387-7.

Electroencephalography Technologist Inter-rater Agreement and Interpretation of Pediatric Critical Care Electroencephalography

OBJECTIVES

Electroencephalography (EEG) technologists commonly screen continuous EEG. Until now, the inter-rater agreement or sensitivity for important EEG findings has been unknown in this group.

METHODS

Twenty-nine EEG technologists and three clinical neurophysiologists interpreted 90 five-minute samples of pediatric critical care EEG. Inter-rater agreement was examined with Cohen's kappa and Fleiss' kappa for EEG findings. A gold-standard consensus agreement was developed for examining sensitivity and specificity for seizures or discontinuity. Kruskal-Wallis tests with Benjamani-Hochberg corrections for multiple comparisons were utilized to examine associations between correct scoring and certification status and years of experience.

RESULTS

Aggregate agreement was moderate for seizures and fair for EEG background continuity among EEG technologists. Individual agreement for seizures and continuity varied from slight to substantial. For individual EEG technologists, sensitivity for seizures ranged from 44 to 93% and sensitivity for continuity ranged from 81 to 100%. Raters with Certified Long Term Monitoring credentials were more likely to identify seizures correctly.

SIGNIFICANCE

This is the first study to evaluate inter-rater agreement and interpretation correctness among EEG technologists interpreting pediatric critical care EEG. EEG technologists demonstrated better aggregate agreement for seizure detection than other EEG findings, yet individual results and internal consistency varied widely. These data provide important insight into the common practice of utilizing EEG technologists for screening critical care EEG.

Measuring clinical uncertainty and equipoise by applying the agreement study methodology to patient management decisions

Background

Clinical uncertainty and equipoise are vague notions that play important roles in contemporary problems of medical care and research, including the design and conduct of pragmatic trials. Our goal was to show how the reliability study methods normally used to assess diagnostic tests can be applied to particular management decisions to measure the degree of uncertainty and equipoise regarding the use of rival management options.

Methods

We first use thrombectomy in acute stroke as an illustrative example of the method we propose. We then review, item by item, how the various design elements of diagnostic reliability studies can be modified in order to measure clinical uncertainty.

Results

The thrombectomy example shows sufficient disagreement and uncertainty to warrant the conduct of additional randomized trials. The general method we propose is that a sufficient number of diverse individual cases sharing a similar clinical problem and covering a wide spectrum of clinical presentations be assembled into a portfolio that is submitted to a variety of clinicians who routinely manage patients with the clinical problem.

Discussion

Clinicians are asked to independently choose one of the predefined management options, which are selected from those that would be compared within a randomized trial that would address the clinical dilemma. Intra-rater agreement can be assessed at a later time with a second evaluation. Various professional judgments concerning individual patients can then be compared and analyzed using kappa statistics or similar methods. Interpretation of results can be facilitated by providing examples or by translating the results into clinically meaningful summary sentences.

Conclusions

Measuring the uncertainty regarding management options for clinical problems may reveal substantial disagreement, provide an empirical foundation for the notion of equipoise, and inform or facilitate the design/conduct of clinical trials to address the clinical dilemma.

Land-Cover Classification Using MaxEnt: Can We Trust in Model Quality Metrics for Estimating Classification Accuracy?

MaxEnt is a popular maximum entropy-based algorithm originally developed for modelling species distribution, but increasingly used for land-cover classification. In this article, we used MaxEnt as a single-class land-cover classification and explored if recommended procedures for generating high-quality species distribution models also apply for generating high-accuracy land-cover classification. We used remote sensing imagery and randomly selected ground-true points for four types of land covers (built, grass, deciduous, evergreen) to generate 1980 classification maps using MaxEnt. We calculated different accuracy discrimination and quality model metrics to determine if these metrics were suitable proxies for estimating the accuracy of land-cover classification outcomes. Correlation analysis between model quality metrics showed consistent patterns for the relationships between metrics, but not for all land-covers. Relationship between model quality metrics and land-cover classification accuracy were land-cover-dependent. While for built cover there was no consistent patterns of correlations for any quality metrics; for grass, evergreen and deciduous, there was a consistent association between quality metrics and classification accuracy. We recommend evaluating the accuracy of land-cover classification results by using proper discrimination accuracy coefficients (e.g., Kappa, Overall Accuracy), and not placing all the confidence in model’s quality metrics as a reliable indicator of land-cover classification results.

Prenatal exposure to valproic acid reduces social responses and alters mRNA levels of opioid receptor and pre-pro-peptide in discrete brain regions of adolescent and adult male rats

Altered social behaviours are a hallmark of several psychiatric and developmental disorders. Clinical and preclinical data have demonstrated that prenatal exposure to valproic acid (VPA), an anti-epileptic and mood stabiliser, is associated with impaired social responses, and thus provides a useful model for the evaluation of neurobiological mechanisms underlying altered social behaviours. The opioid system is widely recognised to regulate and modulate social behaviours, however few studies have examined if the endogenous opioid system is altered in animal models of social impairment. The present study examined social behavioural responses of adolescent and adult male rats prenatally exposed to VPA, and the expression of mRNA encoding opioid receptors and pre-pro-peptides in discrete brain regions. Adolescent and adult rats prenatally exposed to VPA spent less time engaging in social behaviours in the direct social interaction test and exhibited reduced sociability and social novelty preference in the 3-chamber sociability test, compared to saline-treated counterparts. The VPA-exposed adolescent rats exhibited significantly reduced kappa opioid receptor (oprk1) and pre-pro-dynorphin (pdyn) mRNA expression in the cerebral cortex, and reduced oprk1 and nociceptin/orphanin FQ (oprl1) mRNA expression in the hypothalamus. Adult rats prenatally exposed to VPA exhibited decreased mRNA expression of oprk1 and pdyn in hypothalamus, reduced pro-opiomelanocortin(pomc) in the striatum and an increase in delta opioid receptor (oprd1) mRNA in the amygdaloid cortex, when compared to saline-treated counterparts. Mu opioid receptor (oprm1) mRNA expression did not differ between saline and VPA-exposed rats in any region examined. The data demonstrate that impaired social behaviours in adolescent and adult rats prenatally exposed to VPA is accompanied by altered mRNA expression of opioid receptors and pre-pro-peptides in a region specific manner. In particular, both adolescent and adult VPA-exposed rats exhibit reduced oprk1-pdyn mRNA expression in several brain regions, which are associated with deficits in social behavioural responding in the model.

Clinical utility of the Epworth sleepiness scale

PURPOSE

The Epworth sleepiness scale (ESS) is a widely used tool which has been validated as a measure of sleepiness. However, the scores within individual patients referred for clinical sleep services vary considerably which may limit the clinical use of the ESS. We sought to determine the test-retest reliability of the ESS if scores were classified as either normal or sleepy.

METHODS

We measured the ESS in patients presenting to our sleep center at a clinical visit and again when a sleep study was done. Demographic and clinical information was extracted from the electronic medical record.

RESULTS

Average ESS scores were similar on 2 administrations, mean (SD) of 9.8 (5.4) and 10.2 (6.2). Bland-Altman analysis showed upper and lower limits of agreement of 7.5 and - 6.7, respectively. No demographic or clinical variables were identified which contributed to the intra-individual variability. Of the patients who presented with an initial ESS < 11, 80% had a second ESS < 11. Of the patients who presented with an initial ESS ≥ 11, 89% had a second ESS ≥ 11. Cohen's kappa for the two administrations of the ESS was 0.67 (95% CI of 0.51-0.83). Using previously published reports, we calculated Cohen's kappa for polysomnographic determination of the apnea-hypopnea index (AHI) with values ranging from 0.26 to 0.69.

CONCLUSIONS

Individual ESS scores varied considerably within individual patients, but with classification into either normal or sleepy, the test-retest reliability was substantial and in line with other clinical measures including polysomnographic determination of the AHI.

Non-addictive orally-active kappa opioid agonists for the treatment of peripheral pain in rats

Addiction to conventional opioid pain analgesics is a major societal problem that is increasing at an alarming rate. New drugs to combat the effects of opioid abuse are desperately needed. Kappa-opioid agonists are efficacious in peripheral pain models but suffer from centrally-mediated effects. In this article, we discuss our efforts in developing peripheral kappa-based opioid receptor agonists that have the potential analgesic activity of opioids but do not manifest the negative side-effects of opioid use and abuse. Further, derivatives of the tetra-peptide D-Phe-D-Phe-D-Nle-D-Arg-NH2, such as CR665, exhibit high peripheral to central selectivity in analgesic models when administered intravenously (i.v.); however, they are inactive when administered orally. Application of our laboratory's proprietary non-natural amino acid technology to CR665 produced derivatives that exhibit peripheral analgesic activity when dosed orally but do not promote CNS-based effects. Lead compound JT09 activates the kappa-opioid receptor with EC50s in the low nM range, while agonist selectivity for kappa over other peripheral opioid receptors was >33,400 fold. Results indicate that JT09 is approximately as efficacious as morphine in alleviating peripheral pain, while failing to produce undesired CNS-mediated activity. Additionally, JT09 did not promote other CNS-mediated effects associated with morphine (addiction, sedation, dysphoria, tolerance, addiction). Thus, we propose that JT09 has potential for development as a novel analgesic. PERSPECTIVE: This article presents data supporting the analgesic properties of an orally available, peripherally-restricted, kappa-opioid agonist for peripheral pain. A potential out-patient pharmaceutical that acts as efficacious as morphine in alleviating peripheral pain, while failing to produce undesired CNS-mediated effects, could help reduce the current health care burden associated with prescription opioids.

Targeting Peripheral Kappa Opioid Receptors for the Treatment of Chronic Pain: Review Article

Addiction to conventional opioid pain analgesics is a major societal problem that is increasing at an alarming rate. New drugs to combat the effects of opioid abuse are desperately needed. Kappa-opioid agonists are efficacious in peripheral pain models but suffer from centrally-mediated effects. In this review, we discuss our efforts, as well as other's efforts in developing peripheral kappa-based opioid receptor agonists that have the potential analgesic activity of opioids but do not manifest the negative side-effects of opioid use and abuse. Further, derivatives of the tetra peptide D-Phe-D-Phe-D-Nle-D-Arg-NH₂, such as CR665, exhibit high peripheral to central selectivity in analgesic models when administered intravenously (IV); however, they are inactive when administered orally. Application of the JT Pharmaceuticals non-natural amino acid technology to CR665 produced derivatives that exhibit peripheral analgesic activity when dosed orally but do not promote CNS-based effects. Lead compound JT09 activates the kappa-opioid receptor with EC50s in the low nM range, while agonist selectivity for kappa over other peripheral opioid receptors was >33,400 fold. Results indicate that JT09 acts as efficacious as morphine in alleviating peripheral pain, while failing to produce undesired CNS-mediated activity. Additionally, JT09 did not promote other CNS-mediated effects associated with morphine (addiction, sedation, dysphoria, tolerance). Thus, we propose that JT09 has potential for development as a novel analgesic.

A Rare Case of Non-Secretory Multiple Myeloma: A Case Report and Literature Review

Non-secretory myeloma (NSM) is a rare form of myeloma. It is defined as monoclonal plasmocytic proliferation of the bone marrow with the same clinical and radiological manifestations of myeloma. However, plasma cells are unable to secrete immunoglobulin (serum and urinary electrophoresis are negative and free light chain measurement is unquantifiable). This variant of multiple myeloma (MM) usually poses a diagnostic challenge to the biologist and clinician. We report a rare case of non-secretory myeloma in a 76-year-old patient who was diagnosed at the Mohammed V University Hospital Center in Oujda, Morocco.

The Harvard medical practice study trigger system performance in deceased patients

Background

To detect possible threats to quality and safety, multiple systems have been developed. One of them is retrospective chart review. A team of experts scrutinizes medical records, selected by trigger systems, to detect possible adverse events (AEs). The most important AEs and more hints for possible improvement of care appear in deceased patients. Using triggers in a sample of these patients might increase the performance and lower the burden of scrutinizing records without possible preventable AEs. The aim of this study was therefore to determine the performance of the trigger system in a sample of deceased patients and to calculate the specificity and the sensitivity of this trigger system for predicting AEs.

Methods

We performed a study in which the records of deceased patients were screened for triggers by a team of trained nurses. A sample of 100 medical records was randomly selected out of records which had been screened between 2012 and 2015 for the first time, prior to the study in 2016. For the determination of significant differences between the first and second screening, McNemar’s test of symmetry was used. Also, observed agreement, Cohen’s Kappa and prevalence-adjusted and-bias-adjusted-kappa (PABAK) statistics were calculated. This was done for the two trigger rounds on both any trigger present and for every trigger separately.

Results

The observed agreement for any given trigger was 75% with a Kappa and PABAK of 0.5. For the individual triggers, the observed agreement was on average 90%. The corresponding Kappa was on average 0.42 (range: − 0.03-0.78) and the average PABAK was 0.8 (range: 0.44–0.92). Two adverse events were found in cases without triggers previously. The recalculated specificity and sensitivity for the original population were 58 and 92% respectively.

Conclusions

For the reproducibility of triggers it seems that some perform better than others, but on average this is to our opinion suboptimal. The low specificity implies that many records are selected without AEs. This leads to a high false-positive rate making this labour-intensive record review process costly. Therefore, research for better and more expedient systems is required.

Intra and interobserver agreement of narrow band imaging for the detection of head and neck tumors

BACKGROUND

Narrow band imaging (NBI) in combination with white light endoscopy (WLE) has improved the accuracy for the diagnosis and follow-up of head and neck carcinomas by identifying changes in the vascular patterns of the mucosa. However, NBI evaluation is explorer-dependent and may be influenced by the learning curve. The aim of this study is to assess the intra and interobserver agreement of NBI and WLE at the office, under local anaesthesia, by either experienced or non-experienced observers.

METHODS

Eighty-seven images of head and neck lesions were routinely collected under WLE and NBI. A group of three experienced otolaryngologists and three medical students assessed the images after a brief training. No additional patient information was provided. The same protocol was repeated after three weeks. Intra and interobserver agreement were calculated with the kappa index.

RESULTS

NBI intraobserver agreement was substantial (κ = 0.62) and better than with WLE alone, which was moderate (κ = 0.57) in both groups. Interobserver agreement was moderate with WLE (κ = 0.58) and substantial with NBI (κ = 0.63). Both groups improved intraobserver and interobserver agreement with the implementation of NBI.

CONCLUSIONS

Intra and interobserver agreement with NBI for the evaluation of head and neck lesions are substantial, and improve the results of WLE alone in both, professionals and trainees.

Digital epidemiology - Calibrating readers to score dental images remotely

BACKGROUND

There is growing interest to use digital photographs in dental epidemiology. However, the reporting of procedures and metric-based performance outcomes from training to promote data quality prior to actual scoring of digital images has not been optimal.

METHODS

A training study was undertaken to assess training methodology and to select a group of scorers to assess images for dental fluorosis captured during the 2013-2014 National Health and Nutrition Examination Survey (NHANES). Ten examiners and 2 reference examiners assessed dental fluorosis using the Deans Index (DI) and the Thylstrup-Fejerskov (TF) Index. Trainees were evaluated using 128 digital images of upper anterior central incisors at three different periods and with approximately 40 participants during two other periods. Scoring of all digital images was done using a secured, web-based system.

RESULTS

When assessing for nominal fluorosis (apparent vs. non-apparent), the unweighted Kappa for DI ranged from 0.68 to 0.77 and when using an ordinal scale, the linear-weighted kappa for DI ranged from 0.43 to 0.69 during the final evaluation. When assessing for nominal fluorosis using TF, the unweighted Kappa ranged from 0.67 to 0.89 and when using an ordinal scale, the linear-weighted kappa for TF ranged from 0.61 to 0.77 during the final evaluation. No examiner improvement was observed when a clinical assessment feature was added during training to assess dental fluorosis using TF, results using DI was less clear.

CONCLUSION

Providing examiners theoretical material and scoring criteria prior to training may be minimally sufficient to calibrate examiners to score digital photographs. There may be some benefit in providing an in-person training to discuss criteria and review previously scored images. Previous experience as a clinical examiner seems to provide a slight advantage at scoring photographs for DI, but minimizing the number of scorers does improve inter-examiner concordance for both DI and TF.

Predicting Pinus monophylla forest cover in the Baja California Desert by remote sensing

The Californian single-leaf pinyon (Pinus monophylla var. californiarum), a subspecies of the single-leaf pinyon (the world's only one-needled pine), inhabits semi-arid zones of the Mojave Desert (southern Nevada and southeastern California, US) and also of northern Baja California (Mexico). This tree is distributed as a relict subspecies, at elevations of between 1,010 and 1,631 m in the geographically isolated arid Sierra La Asamblea, an area characterized by mean annual precipitation levels of between 184 and 288 mm. The aim of this research was (i) to estimate the distribution of P. monophylla var. californiarum in Sierra La Asamblea by using Sentinel-2 images, and (ii) to test and describe the relationship between the distribution of P. monophylla and five topographic and 18 climate variables. We hypothesized that (i) Sentinel-2 images can be used to predict the P. monophylla distribution in the study site due to the finer resolution (×3) and greater number of bands (×2) relative to Landsat-8 data, which is publically available free of charge and has been demonstrated to be useful for estimating forest cover, and (ii) the topographical variables aspect, ruggedness and slope are particularly important because they represent important microhabitat factors that can determine the sites where conifers can become established and persist. An atmospherically corrected a 12-bit Sentinel-2A MSI image with 10 spectral bands in the visible, near infrared, and short-wave infrared light region was used in combination with the normalized differential vegetation index (NDVI). Supervised classification of this image was carried out using a backpropagation-type artificial neural network algorithm. Stepwise multiple linear binominal logistical regression and Random Forest classification including cross validation were used to model the associations between presence/absence of P. monophylla and the five topographical and 18 climate variables. Using supervised classification of Sentinel-2 satellite images, we estimated that P. monophylla covers 6,653 ± 319 ha in the isolated Sierra La Asamblea. The NDVI was one of the variables that contributed most to the prediction and clearly separated the forest cover (NDVI > 0.35) from the other vegetation cover (NDVI < 0.20). Ruggedness was the most influential environmental predictor variable, indicating that the probability of occurrence of P. monophylla was greater than 50% when the degree of ruggedness terrain ruggedness index was greater than 17.5 m. The probability of occurrence of the species decreased when the mean temperature in the warmest month increased from 23.5 to 25.2 °C. Ruggedness is known to create microclimates and provides shade that minimizes evapotranspiration from pines in desert environments. Identification of the P. monophylla stands in Sierra La Asamblea as the most southern populations represents an opportunity for research on climatic tolerance and community responses to climate variability and change.

Immunological Synapse Predicts Effectiveness of Chimeric Antigen Receptor Cells

Chimeric antigen receptor (CAR)-modified T cell therapy has the potential to improve the overall survival of patients with malignancies by enhancing the effectiveness of CAR T cells. Precisely predicting the effectiveness of various CAR T cells represents one of today’s key unsolved problems in immunotherapy. Here, we predict the effectiveness of CAR-modified cells by evaluating the quality of the CAR-mediated immunological synapse (IS) by quantitation of F-actin, clustering of tumor antigen, polarization of lytic granules (LGs), and distribution of key signaling molecules within the IS. Long-term killing capability, but not secretion of conventional cytokines or standard 4-hr cytotoxicity, correlates positively with the quality of the IS in two different CAR T cells that share identical antigen specificity. Xenograft model data confirm that the quality of the IS in vitro correlates positively with performance of CAR-modified immune cells in vivo. Therefore, we propose that the quality of the IS predicts the effectiveness of CAR-modified immune cells, which provides a novel strategy to guide CAR therapy.

Is a mobile emergency severity index (ESI) triage better than the paper ESI?

This study aims to evaluate the mobile emergency severity index (ESI) tool in terms of validity compared with the original ESI triage. The original ESI and mobile ESI were used with patients at the Department of Emergency Medicine, Ramathibodi Hospital, Thailand. Eligible patients were evaluated by sixth-year medical students/emergency physicians using either the original or mobile ESI. The ESI results for each patient were compared with the standard ESI. Concordance and kappa statistics were calculated for pairs of the evaluators. There were 486 patients enrolled in the study; 235 patients (48.4%) were assessed using the mobile ESI, and 251 patients (51.6%) were in the original ESI group. The baseline characteristics of patients in both groups were mostly comparable except for the ED visit time. The percentages of concordance and kappa statistics in the original ESI group were lower than in the mobile group in all three comparisons (medical students vs gold standard, emergency physicians vs gold standard, and medical students vs emergency physicians). The highest kappa in the original ESI group is 0.69, comparing emergency physicians vs gold standard, while the lowest kappa in the application group is 0.84 comparing the medical students vs gold standard. Both medical students and emergency physicians are more confident with the mobile ESI application triage. In conclusion, the mobile ESI has better inter-rater reliability, and is more user-friendly than the original paper form.

Multiple performance measures are needed to evaluate triage systems in the emergency department

OBJECTIVES

Emergency department triage systems can be considered prediction rules with an ordinal outcome, where different directions of misclassification have different clinical consequences. We evaluated strategies to compare the performance of triage systems and aimed to propose a set of performance measures that should be used in future studies.

STUDY DESIGN AND SETTING

We identified performance measures based on literature review and expert knowledge. Their properties are illustrated in a case study evaluating two triage modifications in a cohort of 14,485 pediatric emergency department visits. Strengths and weaknesses of the performance measures were systematically appraised.

RESULTS

Commonly reported performance measures are measures of statistical association (34/60 studies) and diagnostic accuracy (17/60 studies). The case study illustrates that none of the performance measures fulfills all criteria for triage evaluation. Decision curves are the performance measures with the most attractive features but require dichotomization. In addition, paired diagnostic accuracy measures can be recommended for dichotomized analysis, and the triage-weighted kappa and Nagelkerke's R² for ordinal analyses. Other performance measures provide limited additional information.

CONCLUSION

When comparing modifications of triage systems, decision curves and diagnostic accuracy measures should be used in a dichotomized analysis, and the triage-weighted kappa and Nagelkerke's R² in an ordinal approach.

Selective kappa opioid antagonists for treatment of addiction, are we there yet?

Kappa opioid receptor (KOP) is a G-protein coupled receptor mainly expressed in the cerebral cortex and hypothalamus. It is implicated in nociception, diuresis, emotion, cognition, and immune system functions. KOP agonists possess a strong analgesic effect accompanied by a feeling of dysphoria. On the other hand, antagonists of this receptor were found to block depression, anxiety, and drug-seeking behaviors in animal models. Recently, great interest has been given to the development of selective KOP antagonists as an addiction treatment that does not cause dependence itself or show high relapse rates like the currently used agents. This review provides a comprehensive survey of the KOP antagonists developed for this purpose together with their in vivo studies and clinical trials. In addition, a future perspective and recommendations for the work needed to develop clinically relevant KOP antagonists are presented.

An Evaluation of Interrater Reliability Measures on Binary Tasks Using d-Prime

Many indices of interrater agreement on binary tasks have been proposed to assess reliability, but none has escaped criticism. In a series of Monte Carlo simulations, five such indices were evaluated using d-prime, an unbiased indicator of raters' ability to distinguish between the true presence or absence of the characteristic being judged. Phi and, to a lesser extent, Kappa coefficients performed best across variations in characteristic prevalence, and raters' expertise and bias. Correlations with d-prime for Percentage Agreement, Scott's Pi, and Gwet's AC₁ were markedly lower. In situations where two raters make a series of binary judgments, the findings suggest that researchers should choose Phi or Kappa to assess interrater agreement as the superiority of these indices was least influenced by variations in the decision environment and characteristics of the decision makers.

Endogenous opioid system: a promising target for future smoking cessation medications

BACKGROUND

Nicotine addiction continues to be a health challenge across the world. Despite several approved medications, smokers continue to relapse. Several human and animal studies have evaluated the role of the endogenous opioid system as a potential target for smoking cessation medications.

METHODS

In this review, studies that have elucidated the role of the mu (MORs), delta (DORs), and kappa (KORs) opioid receptors in nicotine reward, nicotine withdrawal, and reinstatement of nicotine seeking will be discussed. Additionally, the review will discuss discrepancies in the literature and therapeutic potential of the endogenous opioid system, and suggest studies to address gaps in knowledge with respect to the role of the opioid receptors in nicotine dependence.

RESULTS

Data available till date suggest that blockade of the MORs and DORs decreased the rewarding effects of nicotine, while activation of the MORs and DORs decreased nicotine withdrawal-induced aversive effects. In contrast, activation of the KORs decreased the rewarding effects of nicotine, while blockade of the KORs decreased nicotine withdrawal-induced aversive effects. Interestingly, blockade of the MORs and KORs attenuated reinstatement of nicotine seeking. In humans, MOR antagonists have shown benefits in select subpopulations of smokers and further investigation is required to realize their full therapeutic potential.

CONCLUSION

Future work must assess the influence of polymorphisms in opioid receptor-linked genes in nicotine dependence, which will help in both identifying individuals vulnerable to nicotine addiction and the development of opioid-based smoking cessation medications. Overall, the endogenous opioid system continues to be a promising target for future smoking cessation medications.

The RAMA Ped Card: Does it work for actual weight estimation in child patients at the emergency department

BACKGROUND

In emergency conditions, the actual weight of infants and young children are essential for treatments. The RAMATHIBODI Pediatric Emergency Drug Card or RAMA Ped Card has also been developed to estimate actual weight of the subjects. This study aimed to validate the RAMA Ped Card in correctly identifying the actual weight of infants and young adults.

METHODS

This study was a prospective study. We enrolled all consecutive patients under 15 years of age who visited the emergency department (ED). All eligible patients' actual weight and height were measured at the screening point of the ED. The weight of each patient was also measured using the unlabeled RAMA Ped Card. The Cohen's kappa values and agreement percentages were calculated.

RESULTS

During the study period, there were 345 eligible patients. The RAMA Ped Card had a 61.16% agreement with the actual weight with a kappa of 0.54 (P<0.01), while the agreement with the actual height had a kappa of 0.90 and 91.59% agreement. Sub-group analysis found kappa scores with good range in two categories: in cases of accidents and in the infant group (kappa of 0.68 and 0.65, respectively).

CONCLUSION

The RAMA Ped Card had a fair correlation with the actual weight in child patients presenting at the ED. Weight estimation in infant patients and children who presented with accidents were more accurate.

Interrater reliability of schizoaffective disorder compared with schizophrenia, bipolar disorder, and unipolar depression - A systematic review and meta-analysis

Schizoaffective disorder is a common diagnosis in clinical practice but its nosological status has been subject to debate ever since it was conceptualized. Although it is key that diagnostic reliability is sufficient, schizoaffective disorder has been reported to have low interrater reliability. Evidence based on systematic review and meta-analysis methods, however, is lacking. Using a highly sensitive literature search in Medline, Embase, and PsycInfo we identified studies measuring the interrater reliability of schizoaffective disorder in comparison to schizophrenia, bipolar disorder, and unipolar disorder. Out of 4126 records screened we included 25 studies reporting on 7912 patients diagnosed by different raters. The interrater reliability of schizoaffective disorder was moderate (meta-analytic estimate of Cohen's kappa 0.57 [95% CI: 0.41-0.73]), and substantially lower than that of its main differential diagnoses (difference in kappa between 0.22 and 0.19). Although there was considerable heterogeneity, analyses revealed that the interrater reliability of schizoaffective disorder was consistently lower in the overwhelming majority of studies. The results remained robust in subgroup and sensitivity analyses (e.g., diagnostic manual used) as well as in meta-regressions (e.g., publication year) and analyses of publication bias. Clinically, the results highlight the particular importance of diagnostic re-evaluation in patients diagnosed with schizoaffective disorder. They also quantify a widely held clinical impression of lower interrater reliability and agree with earlier meta-analysis reporting low test-retest reliability.

Concordance of Demographic Characteristics, Sexual Behaviors, and Relationship Attributes Among Sex Dyads of Black and White Men Who Have Sex with Men

Differences in individual behaviors have failed to explain racial disparities between Black and White men who have sex with men (MSM). However, reporting of behaviors and partner characteristics are assumed to be non-differentially reported by race. From 314 participants, this study used the two-sided data-where sexual partners provide information on each other and their relationship-of 127 dyads of Black and White MSM from Atlanta, GA, to assess the reliability of partner-reported demographic characteristics and the concordance of sexual behaviors and partnership attributes by race. We compared proportions of concordance by race using a modified kappa (K m) to assess chance-corrected agreement. The median difference in age between self- and partner-reports was 0 (0-1) years. Compared to self-reports, 97 % of the partners of Black participants and 96 % of the partners of White participants correctly classified their race. We observed poor agreement on pre-sexual discussion (K m = 0.18) and being in an ongoing relationship (K m = 0.13), with no differences by race (p = 0.11). Although not statistically significant, Black MSM dyads had lower levels of concordance for unprotected anal intercourse in the previous 12 months (68 %) compared to White dyads (90 %), with fair agreement among Black dyads (K m = 0.26). Measures of partner-reported age and race are likely accurate; however, certain self-reported sexual behaviors and partnership attributes may be unreliable and differentially reported by race. Our findings highlight the need to assess the validity of measures used to estimate HIV transmission and inform racial disparities research.

What is a representative voiding pattern in children with lower urinary tract symptoms? Lack of consistent findings in ambulatory and conventional urodynamic tests

BACKGROUND

Conventional urodynamics (CU) is a highly standardized evaluation of lower urinary tract function. However, in pediatric patients there is concern that the reliability of measurements could be influenced by development effects and measurement variability, as well as by the unfamiliar clinical environment. Ambulatory urodynamics (AU) provides an alternative to this - it uses natural filling, is measured over a prolonged period, and is conducted in a child-friendly environment.

OBJECTIVE

The aim of this study was to conduct a comparative analysis of AU and CU to evaluate the consistency in voiding patterns obtained with these two methods of urodynamic testing.

STUDY DESIGN

Urodynamic parameters obtained by AU and CU methods in 50 pediatric patients aged >5 years were retrospectively analyzed. Voiding patterns were categorized into six types: coordinated contraction, detrusor after-contraction, fluctuated contraction, pre-void contraction, relief voiding, and weak or absent contraction. Voiding patterns were used to determine the repeatability within urodynamic tests and to identify consistency between AU and CU tests. Five urodynamic parameters were quantified and compared between AU and CU: voided volume, flow rate, maximum detrusor pressure, and detrusor pressure at peak flow rate. For inter-observer variation analysis, 100 voiding curves were randomly selected and categorized by two independent observers; inter-observer agreement was evaluated using the kappa statistic.

RESULTS

A single pattern of voiding was identified in five patients using AU and 37 using CU. Consistency of a single pattern between AU and CU was identified in three patients, and consistency between a predominant pattern with AU, defined by one type of voiding occurring >50% of one's voids, and a single pattern with CU was identified in 10 patients (summary table). Flow rates were similar between methods; however, higher maximum detrusor pressure and detrusor pressure at peak flow and lower voided volume were recorded with AU.

DISCUSSION

AU resulted in more diverse voiding patterns. Along with the differences in measured urodynamic parameters challenges the application of findings from one method to form a clinical diagnosis. Furthermore, CU may not be as sensitive as AU to the variability in lower urinary tract pathophysiology.

CONCLUSIONS

More diverse voiding patterns were identified in AU compared with CU, with a lack of consistency in identified voiding pattern in both methods. Therefore, the urodynamic findings in children may have to be analyzed in more detail, taking the variations into account.

Proliferative glomerulonephritis with monoclonal immunoglobulin deposition disease: The utility of routine staining with immunoglobulin light chains

Proliferative glomerulonephritis occurring as a consequence of monoclonal glomerular deposits of IgG is uncommon. It is a form of renal involvement in monoclonal gammopathy that mimics immune complex glomerulonephritis. Here, we report the first series of proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) from the Indian subcontinent highlighting use of light chain immunofluorescence (IF) in routine renal biopsy interpretation. We retrieved 6 patients diagnosed as proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) out of 160 biopsies (3.7%) with membranoproliferative patterns over 5 1/2 years (2009-2014), one of whom had recurrence 6 months post-renal transplant. Four (67%) patients presented with rapidly progressive renal failure and two (33%) with nephrotic syndrome. None of these patients had overt multiple myeloma. The predominant histologic pattern was membranoproliferative with all the biopsies showing IgG3 Kappa deposits on IF. The deposits were primarily subendothelial on electron microscopy.

Comment on Alquraini et al.: reliability of Canadian Emergency Department Triage and Acuity Scale (CTAS) in Saudi Arabia

It is very common to examine reliability of triage scales using (weighted) kappa statistics. The point is that weighted kappa has grossly underestimated disagreements by one category and put more emphasis on extreme category disagreements; therefore, low prevalence of critically-ill and non-urgent patients has excluded the effect of extreme categories disagreement from calculated kappa coefficient and also contributed to significant overestimation. As a result, weighted kappa coefficient as an estimate of scale reliability is overestimated by the anchoring effect.

Test-retest reliability of health behavior items in the Community Health Survey in South Korea

OBJECTIVES

Responses to health-related items on the Community Health Survey (CHS) provide evidence that is used to develop community-based health policy. This study aimed to assess the test-retest reliability of selected health behavioral items on the CHS according to item category, response period, and response scale.

METHODS

A sample of 159 men and women 20 to 69 years of age participated in a test-retest with an interval of 14 to 21 days. A total of 28 items relating to smoking, alcohol consumption, diet and weight control, and mental health were selected. We evaluated the test-retest reliability of the items using kappa statistics.

RESULTS

Kappa values ranged from 0.44 to 0.93. Items concerning habits had higher kappa values (mean, 0.7; standard error, 0.05) than items concerning awareness or attitudes (p=0.012). The kappa value of items with two- to four-point scales was 0.63, which was higher than the value of 0.59 for items with scales involving five or more points, although this difference was not statistically significant. Different kappa values were observed for each reference period, but no statistically significant differences were noted.

CONCLUSIONS

The test-retest reliability of the CHS items that we studied was associated with item category. Further study of the relationship between item category and reliability in domains other than health behaviors is required.

Do the tuberculin skin test and the QuantiFERON-TB Gold in-tube test agree in detecting latent tuberculosis among high-risk contacts? A systematic review and meta-analysis

OBJECTIVES:

The QuantiFERON-TB Gold in-tube test (QFT-GIT) and the tuberculin skin test (TST) are used to diagnose latent tuberculosis infection (LTBI). However, conclusive evidence regarding the agreement of these two tests among high risk contacts is lacking. This systematic review and meta-analysis aimed to estimate the agreement between the TST and the QFT-GIT using kappa statistics.

METHODS:

According to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines, scientific databases including PubMed, Scopus, and Ovid were searched using a targeted search strategy to identify relevant studies published as of June 2015. Two researchers reviewed the eligibility of studies and extracted data from them. The pooled kappa estimate was determined using a random effect model. Subgroup analysis, Egger’s test and sensitivity analysis were also performed.

RESULTS:

A total of 6,744 articles were retrieved in the initial search, of which 24 studies had data suitable for meta-analysis. The pooled kappa coefficient and prevalence-adjusted bias-adjusted kappa were 0.40 (95% confidence interval [CI], 0.34 to 0.45) and 0.45 (95% CI, 0.38 to 0.49), respectively. The results of the subgroup analysis found that age group, quality of the study, location, and the TST cutoff point affected heterogeneity for the kappa estimate. No publication bias was found (Begg’s test, p=0.53; Egger’s test, p=0.32).

CONCLUSIONS:

The agreement between the QFT-GIT and the TST in diagnosing LTBI among high-risk contacts was found to range from fair to moderate.