A time-dependent Poisson-Gamma model for recruitment forecasting in multicenter studies

Forecasting recruitments is a key component of the monitoring phase of multicenter studies. One of the most popular techniques in this field is the Poisson-Gamma recruitment model, a Bayesian technique built on a doubly stochastic Poisson process. This approach is based on the modeling of enrollments as a Poisson process where the recruitment rates are assumed to be constant over time and to follow a common Gamma prior distribution. However, the constant-rate assumption is a restrictive limitation that is rarely appropriate for applications in real studies. In this paper, we illustrate a flexible generalization of this methodology which allows the enrollment rates to vary over time by modeling them through B-splines. We show the suitability of this approach for a wide range of recruitment behaviors in a simulation study and by estimating the recruitment progression of the Canadian Co-infection Cohort.

Intravenous Magnesium: Prompt Use for Asthma in Children Treated in the Emergency Department (IMPACT-ED): Protocol for a Multicenter Pilot Randomized Controlled Trial

BACKGROUND

Children managed for asthma in an emergency department (ED) may be less likely to be hospitalized if they receive intravenous magnesium sulfate (IVMg). Asthma guidelines recommend IVMg for severely sick children but note a lack of evidence to support this recommendation. All previous trials of IVMg in children with asthma have been too small to answer whether IVMg is effective and safe. A few major questions remain about IVMg. First, it has not been tested early in the course of ED treatment, when the impact on hospitalization would be greatest. Second, the clinical impact of hypotension, a known adverse effect of IVMg, has not been well characterized in previous research. Third, no trials have compared different IVMg doses or serial serum magnesium (total and ionized) concentrations to optimize dosing, so the most effective dose is unknown. A large, conclusive, randomized, placebo-controlled clinical trial of IVMg might be challenging due to the need to enroll and complete study procedures quickly, a lack of understanding of blood pressure changes after IVMg, and a lack of pharmacologic information to guide the optimal doses of IVMg to be tested. Therefore, a pilot study to inform the above gaps is warranted before conducting a definitive trial.

OBJECTIVE

The objectives of this study are to (1) demonstrate the feasibility of enrolling children with severe acute asthma in the ED in a multicenter, randomized controlled trial of a placebo, low-dose IVMg, or high-dose IVMg; (2) demonstrate the feasibility of timely delivery of study medication, assessment of blood pressure, and evaluation of adverse events in a standardized protocol; and (3) externally validate a previously constructed pharmacokinetic model and develop a combined pharmacokinetic/pharmacodynamic model for IVMg using magnesium (total and ionized) serum concentrations and their correlation with measures of efficacy and safety.

METHODS

This pilot trial tests procedures and gathers information to plan a definitive trial. The pilot trial will enroll as many as 90 children across 3 sites, randomize each child to 1 of 3 study arms, measure blood pressure frequently, and collect 3 blood samples from each participant with corresponding clinical asthma scores.

RESULTS

The project was funded by the National Heart, Lung, and Blood Institute (1 R34HL152047-2) in March 2022. Enrollment began in September 2022, and 43 children have been enrolled as of April 2023. We will submit the results for publication in late 2023.

CONCLUSIONS

The results of this study will guide the planning of a large, definitive, multicenter trial powered to evaluate if IVMg reduces hospitalization. Blood pressure measurements will inform a monitoring plan for the larger trial, and blood samples and asthma scores will be used to validate pharmacologic models to select the optimal dose of IVMg to be evaluated in the definitive trial.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05166811; https://clinicaltrials.gov/ct2/show/NCT05166811.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/48302.

Outcomes of shared institutional review board compared with multiple individual site institutional review board models in a multisite clinical trial

BACKGROUND

Institutional review boards play a crucial role in initiating clinical trials. Although many multicenter clinical trials use an individual institutional review board model, where each institution uses their local institutional review board, it is unknown if a shared (single institutional review board) model would reduce the time required to approve a standard institutional review board protocol.

OBJECTIVE

This study aimed to compare processing times and other processing characteristics between sites using a single institutional review board model and those using their individual site institutional review board model in a multicenter clinical trial.

STUDY DESIGN

This was a retrospective study of sites in an open-label, multicenter randomized control trial from 2014 to 2021. Participating sites in the multicenter Chronic Hypertension and Pregnancy trial were asked to complete a survey collecting data describing their institutional review board approval process.

RESULTS

A total of 45 sites participated in the survey (7 used a shared institutional review board model and 38 used their individual institutional review board model). Most sites (86%) using the shared institutional review board model did not require a full-board institutional review board meeting before protocol approval, compared with 1 site (3%) using the individual institutional review board model (P<.001). Median total approval times (41 vs 56 days; P=.42), numbers of submission rounds (1 vs 2; P=.09), and numbers of institutional review board stipulations (1 vs 4; P=.12) were lower for the group using the shared institutional review board model than those using the individual site institutional review board model; however, these differences were not statistically significant.

CONCLUSION

The findings supported the hypothesis that the shared institutional review board model for multicenter studies may be more efficient in terms of cumulative time and effort required to obtain approval of an institutional review board protocol than the individual institutional review board model. Given that these data have important implications for multicenter clinical trials, future research should evaluate these findings using larger or multiple multicenter trials.

Variability in Ethics Review for Multicenter Protocols in Buenos Aires, Argentina. An Observational Study

It has been reported that significant variability in the ethics review process affects multisite studies. We analyzed 1,305 applications for multicenter studies (409 unique protocols), from 1^st January 2020 to 20^th September 2021. We examined the variability in the times to approval and the first observation and the variation in the level of risk assigned. The median [IQR] variabilities were 42.19 [15.23-82.36] days and 8.00 [3.12-16.68] days, for the times to approval and to the first observation, respectively. There was disagreement in the level of risk assigned by the Research Ethics Committee (REC) in 24.0% of cases. Independent predictors of variability included the number of REC members. In our study, we found substantial variability in the ethics review process among health research protocols. Also, we describe methods to readily measure the delays and the variations in the ethics review process.

Harmonization Strategies in Multicenter MRI-Based Radiomics

Radiomics analysis is a powerful tool aiming to provide diagnostic and prognostic patient information directly from images that are decoded into handcrafted features, comprising descriptors of shape, size and textural patterns. Although radiomics is gaining momentum since it holds great promise for accelerating digital diagnostics, it is susceptible to bias and variation due to numerous inter-patient factors (e.g., patient age and gender) as well as inter-scanner ones (different protocol acquisition depending on the scanner center). A variety of image and feature based harmonization methods has been developed to compensate for these effects; however, to the best of our knowledge, none of these techniques has been established as the most effective in the analysis pipeline so far. To this end, this review provides an overview of the challenges in optimizing radiomics analysis, and a concise summary of the most relevant harmonization techniques, aiming to provide a thorough guide to the radiomics harmonization process.

Consent Builder: an innovative tool for creating research informed consent documents

Objective

To describe process innovations related to research informed consent documents, and development and formative evaluation of Consent Builder, a platform for generating consent documents for multicenter studies.

Materials and Methods

Analysis of Institutional Review Board workflows and documents, followed by process redesign, document redesign, and software development. Locally developed software leverages REDCap and LaTeX. A small-scale usability study was conducted.

Results

Process innovations were combining document types, and conceptualizing 2-part informed consent documents: part 1 standardizing the study description and part 2 with local site verbiage. Consent Builder was implemented in the Trial Innovation Network. User survey scores were acceptable; but areas for improvement were noted. LaTeX coding was the biggest challenge for users.

Discussion

The process changes were generally well accepted. The software implementation uncovered un-accounted for assumptions, and variability in IRB review workflow across centers. Technical modifications may be needed before widespread implementation.

Conclusion

We demonstrated proof-of-concept of an approach to generate research consent documents that are consistent across sites in study description, but which allow for customization of local site verbiage. The Consent Builder tool is an example of an operational innovation, helping meet a need that arose in part due to regulations around use of Single IRB for multicenter trials.

Register, multicenter and genome-wide association studies in hidradenitis suppurativa

The European Hidradenitis Suppurativa Foundation (EHSF) e.V. has taken several initiatives to collaborative studies. They result from the data of the European Registry of Hidradenitis Suppurativa (ERHS) based on the knowledge obtained from the regional Northern countries (HISREG) and Italian (IRHIS) registries and the real-world data generated from claims data from insurance databases. Multicenter studies, such as the Hidradenitis Suppurativa collaborative study of subtypes (HORUS) and the Global Hidradenitis Suppurativa Atlas (GHISA) are planned to provide an ideal complement to the register studies. Most recently, the role of EHSF as a coordinator or key player is being explored in multiple genetic studies, such as a genome-wide association study (GWAS) and the exome sequencing and cellular/molecular profiling project, which will speed up gene and drug discovery in HS.

A Thrombomodulin Promoter Gene Polymorphism, rs2239562, Influences Both Susceptibility to and Outcome of Sepsis

Objective: Disseminated intravascular coagulation plays a key role in the pathophysiology of sepsis. Thrombomodulin is essential in the protein C system of coagulation cascade, and functional polymorphisms influence the human thrombomodulin gene (THBD). Therefore, we conducted a multicenter study to evaluate the influence of such polymorphisms on the pathophysiology of sepsis. Methods: A collaborative case-control study in the intensive care unit (ICU) of each of five tertiary emergency centers. The study included 259 patients (of whom 125 displayed severe sepsis), who were admitted to the ICU of Chiba University Hospital, Chiba, Japan between October 2001 and September 2008 (discovery cohort) and 793 patients (of whom 271 patients displayed severe sepsis), who were admitted to the five ICUs between October 2008 and September 2012 (multicenter validation cohort). To assess the susceptibility to severe sepsis, we further selected 222 critically ill patients from the validation cohort matched for age, gender, morbidity, and severity with the patients with severe sepsis, but without any evidence of sepsis. Results: We examined whether the eight THBD single nucleotide polymorphisms (SNPs) were associated with susceptibility to and/or mortality of sepsis. Higher mortality on severe sepsis in the discovery and combined cohorts was significantly associated with the CC genotype in a THBD promoter SNP (-1920^*C/G; rs2239562) [odds ratio [OR] 2.709 (1.067-6.877), P = 0.033 and OR 1.768 (1.060-2.949), P = 0.028]. Furthermore, rs2239562 SNP was associated with susceptibility to severe sepsis [OR 1.593 (1.086-2.338), P = 0.017]. Conclusions: The data demonstrate that rs2239562, the THBD promoter SNP influences both the outcome and susceptibility to severe sepsis.

Early Predictors of Employment Status One Year Post Injury in Individuals with Traumatic Brain Injury in Europe

Sustaining a traumatic brain injury (TBI) often affects the individual’s ability to work, reducing employment rates post-injury across all severities of TBI. The objective of this multi-country study was to assess the most relevant early predictors of employment status in individuals after TBI at one-year post-injury in European countries. Using a prospective longitudinal non-randomized observational cohort (The Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI) project), data was collected between December 2014–2019 from 63 trauma centers in 18 European countries. The 1015 individuals who took part in this study were potential labor market participants, admitted to a hospital and enrolled within 24 h of injury with a clinical TBI diagnosis and indication for a computed tomography (CT) scan, and followed up at one year. Results from a binomial logistic regression showed that older age, status of part-time employment or unemployment at time of injury, premorbid psychiatric problems, and higher injury severity (as measured with higher Injury severity score (ISS), lower Glasgow Coma Scale (GCS), and longer length of stay (LOS) in hospital) were associated with higher unemployment probability at one-year after injury. The study strengthens evidence for age, employment at time of injury, premorbid psychiatric problems, ISS, GCS, and LOS as important predictors for employment status one-year post-TBI across Europe.

The Longitudinal Associations of Perceived Neighborhood Disorder and Lack of Social Cohesion With Depression Among Adults Aged 50 Years or Older: An Individual-Participant-Data Meta-Analysis From 16 High-Income Countries

Although residential environment might be an important predictor of depression among older adults, systematic reviews point to a lack of longitudinal investigations, and the generalizability of the findings is limited to a few countries. We used longitudinal data collected between 2012 and 2017 in 3 surveys including 15 European countries and the United States and comprising 32,531 adults aged 50 years or older. The risk of depression according to perceived neighborhood disorder and lack of social cohesion was estimated using 2-stage individual-participant-data meta-analysis; country-specific parameters were analyzed by meta-regression. We conducted additional analyses on retired individuals. Neighborhood disorder (odds ratio (OR) = 1.25) and lack of social cohesion (OR = 1.76) were significantly associated with depression in the fully adjusted models. In retirement, the risk of depression was even higher (neighborhood disorder: OR = 1.35; lack of social cohesion: OR = 1.93). Heterogeneity across countries was low and was significantly reduced by the addition of country-level data on income inequality and population density. Perceived neighborhood problems increased the overall risk of depression among adults aged 50 years or older. Policies, especially in countries with stronger links between neighborhood and depression, should focus on improving the physical environment and supporting social ties in communities, which can reduce depression and contribute to healthy aging.

Validity of Privacy-Protecting Analytical Methods That Use Only Aggregate-Level Information to Conduct Multivariable-Adjusted Analysis in Distributed Data Networks

Distributed data networks enable large-scale epidemiologic studies, but protecting privacy while adequately adjusting for a large number of covariates continues to pose methodological challenges. Using 2 empirical examples within a 3-site distributed data network, we tested combinations of 3 aggregate-level data-sharing approaches (risk-set, summary-table, and effect-estimate), 4 confounding adjustment methods (matching, stratification, inverse probability weighting, and matching weighting), and 2 summary scores (propensity score and disease risk score) for binary and time-to-event outcomes. We assessed the performance of combinations of these data-sharing and adjustment methods by comparing their results with results from the corresponding pooled individual-level data analysis (reference analysis). For both types of outcomes, the method combinations examined yielded results identical or comparable to the reference results in most scenarios. Within each data-sharing approach, comparability between aggregate- and individual-level data analysis depended on adjustment method; for example, risk-set data-sharing with matched or stratified analysis of summary scores produced identical results, while weighted analysis showed some discrepancies. Across the adjustment methods examined, risk-set data-sharing generally performed better, while summary-table and effect-estimate data-sharing more often produced discrepancies in settings with rare outcomes and small sample sizes. Valid multivariable-adjusted analysis can be performed in distributed data networks without sharing of individual-level data.

The efficiency of single institutional review board review in National Institute of Child Health and Human Development Cooperative Reproductive Medicine Network-initiated clinical trials

BACKGROUND/AIMS

Timely review of research protocols by institutional review boards leads to more rapid initiation of clinical trials, which is critical to expeditious translation from bench to bedside. This observational study examined the impact of a single institutional review board on time and efforts required to initiate clinical trials by the National Institute of Child Health and Human Development Cooperative Reproductive Medicine Network.

METHODS

Collection of data from the same six main clinical sites for three current clinical trials and two past clinical trials, including time from institutional review board submission to approval, pages submitted, consent form length, number of required attachments, other regulatory requirements, order of review at central or local sites, and language in documents at individual participating sites. Results from two past clinical trials were also included.

RESULTS

While time required for actual institutional review board submission's review and initial approval was reduced with use of a single institutional review board for multicenter trials (from a mean of 66.7-24.0 days), total time was increased (to a mean of 111.2 or 123.3 days). In addition to single institutional review board approval, all institutions required local approval of some components (commonly consent language and use of local language), which varied considerably. The single institutional review board relied on local institutions for adding or removing personnel, conflict of interest review, and auditing of activities.

CONCLUSION

A single institutional review board reduced time for initial review and approval of protocols and informed consents, although time for the entire process was increased, as individual institutions retained oversight of components of required regulatory review. In order to best achieve the National Institute of Health's goals for improved efficiency in initiation and conduct of multisite clinical research, greater coordination with local institutional review boards is key to streamlining and accelerating initiation of multisite clinical research.

Ankle Strength Impairments in Myotonic Dystrophy Type 1: A Five-Year Follow-up

BACKGROUND

In Myotonic Dystrophy type 1 (DM1) patients, ankle muscles are affected early and this impairment is reported to be a good biological marker for longitudinal studies.

OBJECTIVE

To characterize the ankle dorsiflexion (DF) and eversion (EV) maximal isometric muscle strength changes in adult DM1 patients over 5 years using a standardized handheld dynamometer protocol and the Myoankle method, compare the changes measured with both methods and to the standard error of measurement, and verify the relationship between ankle muscle strength and gait performance.

METHODS

The maximal isometric muscle strength of ankle DF and EV in DM1 patients from Quebec and Lyon was assessed at baseline, 18, 36 and 60 months using a handheld dynamometer (HHD) protocol and the MyoAnkle method.

RESULTS

There was a decrease of torque in DF/EV of 36.0% /31.3% and 27.7% /35.5% for the Quebec and Lyon cohorts respectively (p≤0.01), but not in a linear way. In most cases (82.5%), the changes observed were greater than the standard error of measurement. DF torque measures taken by the two methods (HHD and MyoAnkle) were highly correlated (rp = 0.97-0.98, p < 0.001).

CONCLUSION

Muscle strength ankle impairments are clinically meaningful in DM1 and can be accurately monitored using quantitative testing to measure the efficacy of therapeutic trials.

Stakeholders' views on data sharing in multicenter studies

AIM

To understand stakeholders' views on data sharing in multicenter comparative effectiveness research studies and the value of privacy-protecting methods.

MATERIALS & METHODS

Semistructured interviews with five US stakeholder groups.

RESULTS

We completed 11 interviews, involving patients (n = 15), researchers (n = 10), Institutional Review Board and regulatory staff (n = 3), multicenter research governance experts (n = 2) and healthcare system leaders (n = 4). Perceptions of the benefits and value of research were the strongest influences toward data sharing; cost and security risks were primary influences against sharing. Privacy-protecting methods that share summary-level data were acknowledged as being appealing, but there were concerns about increased cost and potential loss of research validity.

CONCLUSION

Stakeholders were open to data sharing in multicenter studies that offer value and minimize security risks.

Improving site selection in clinical studies: a standardised, objective, multistep method and first experience results

INTRODUCTION

A considerable number of clinical studies experience delays, which result in increased duration and costs. In multicentre studies, patient recruitment is among the leading causes of delays. Poor site selection can result in low recruitment and bad data quality. Site selection is therefore crucial for study quality and completion, but currently no specific guidelines are available.

MATERIAL AND METHODS

Selection of sites adequate to participate in a prospective multicentre cohort study was performed through an open call using a newly developed objective multistep approach. The method is based on use of a network, definition of objective criteria and a systematic screening process.

ILLUSTRATIVE EXAMPLE OF THE METHOD AT WORK

Out of 266 interested sites, 24 were shortlisted and finally 12 sites were selected to participate in the study. The steps in the process included an open call through a network, use of selection questionnaires tailored to the study, evaluation of responses using objective criteria and scripted telephone interviews. At each step, the number of candidate sites was quickly reduced leaving only the most promising candidates. Recruitment and quality of data went according to expectations in spite of the contracting problems faced with some sites.

CONCLUSION

The results of our first experience with a standardised and objective method of site selection are encouraging. The site selection method described here can serve as a guideline for other researchers performing multicentre studies.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT02297581.

Clinical epidemiology in the era of big data: new opportunities, familiar challenges

Routinely recorded health data have evolved from mere by-products of health care delivery or billing into a powerful research tool for studying and improving patient care through clinical epidemiologic research. Big data in the context of epidemiologic research means large interlinkable data sets within a single country or networks of multinational databases. Several Nordic, European, and other multinational collaborations are now well established. Advantages of big data for clinical epidemiology include improved precision of estimates, which is especially important for reassuring (“null”) findings; ability to conduct meaningful analyses in subgroup of patients; and rapid detection of safety signals. Big data will also provide new possibilities for research by enabling access to linked information from biobanks, electronic medical records, patient-reported outcome measures, automatic and semiautomatic electronic monitoring devices, and social media. The sheer amount of data, however, does not eliminate and may even amplify systematic error. Therefore, methodologies addressing systematic error, clinical knowledge, and underlying hypotheses are more important than ever to ensure that the signal is discernable behind the noise.

Longer-Term Investigation of the Value of 18F-FDG-PET and Magnetic Resonance Imaging for Predicting the Conversion of Mild Cognitive Impairment to Alzheimer's Disease: A Multicenter Study

BACKGROUND

The value of fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) and magnetic resonance imaging (MRI) for predicting conversion of mild cognitive impairment (MCI) to Alzheimer's disease (AD) in longer-term is unclear.

OBJECTIVE

To evaluate longer-term prediction of MCI to AD conversion using 18F-FDG-PET and MRI in a multicenter study.

METHODS

One-hundred and fourteen patients with MCI were followed for 5 years. They underwent clinical and neuropsychological examinations, 18F-FDG-PET, and MRI at baseline. PET images were visually classified into predefined dementia patterns. PET scores were calculated as a semi quantitative index. For structural MRI, z-scores in medial temporal area were calculated by automated volume-based morphometry (VBM).

RESULTS

Overall, 72% patients with amnestic MCI progressed to AD during the 5-year follow-up. The diagnostic accuracy of PET scores over 5 years was 60% with 53% sensitivity and 84% specificity. Visual interpretation of PET images predicted conversion to AD with an overall 82% diagnostic accuracy, 94% sensitivity, and 53% specificity. The accuracy of VBM analysis presented little fluctuation through 5 years and it was highest (73%) at the 5-year follow-up, with 79% sensitivity and 63% specificity. The best performance (87.9% diagnostic accuracy, 89.8% sensitivity, and 82.4% specificity) was with a combination identified using multivariate logistic regression analysis that included PET visual interpretation, educational level, and neuropsychological tests as predictors.

CONCLUSION

18F-FDG-PET visual assessment showed high performance for predicting conversion to AD from MCI, particularly in combination with neuropsychological tests. PET scores showed high diagnostic specificity. Structural MRI focused on the medial temporal area showed stable predictive value throughout the 5-year course.

Update on the Methodological Quality of Research Published in The American Journal of Sports Medicine: Comparing 2011-2013 to 10 and 20 Years Prior

BACKGROUND

In recent years, the number of articles in The American Journal of Sports Medicine (AJSM) has risen dramatically, with an increasing emphasis on evidence-based medicine in orthopaedics and sports medicine.

HYPOTHESIS

Despite the increase in the number of articles published in AJSM over the past decade, the methodological quality of articles in 2011-2013 has improved relative to those in 2001-2003 and 1991-1993.

STUDY DESIGN

Meta-analysis.

METHODS

All articles published in AJSM during 2011-2013 were reviewed and classified by study design. For each article, the use of pertinent methodologies, such as prospective data collection, randomization, control groups, and blinding, was recorded. The frequency of each article type and the use of evidence-based techniques were compared relative to 1991-1993 and 2001-2003 by use of Pearson χ(2) testing.

RESULTS

The number of research articles published in AJSM more than doubled from 402 in 1991-1993 and 423 in 2001-2003 to 953 in 2011-2013. Case reports decreased from 15.2% to 10.6% to 2.1% of articles published over the study period (P < .001). Cadaveric/human studies and meta-analysis/literature review studies increased from 5.7% to 7.1% to 12.4% (P < .001) and from 0.2% to 0.9% to 2.3% (P = .01), respectively. Randomized, prospective clinical trials increased from 2.7% to 5.9% to 7.4% (P = .007). Fewer studies used retrospective compared with prospective data collection (P < .001). More studies tested an explicit hypothesis (P < .001) and used controls (P < .001), randomization (P < .001), and blinding of those assessing outcomes (P < .001). Multi-investigator trials increased (P < .001), as did the proportion of articles citing a funding source (P < .001).

CONCLUSION

Despite a dramatic increase in the number of published articles, the research published in AJSM shifted toward more prospective, randomized, controlled, and blinded designs during 2011-2013 compared with 2001-2003 and 1991-1993, demonstrating a continued improvement in methodological quality.

Twenty-month follow-up of occlusal caries lesions deemed questionable at baseline: findings from the National Dental Practice-Based Research Network

BACKGROUND

A questionable occlusal caries (QOC) lesion can be defined as an occlusal surface with no radiographic evidence of caries, but caries is suspected because of clinical appearance. In this study, the authors report the results of a 20-month follow-up of these lesions.

METHODS

Fifty-three clinicians from The National Dental Practice-Based Research Network participated in this study, recording lesion characteristics at baseline and lesion status at 20 months.

RESULTS

At baseline, 1,341 QOC lesions were examined; the treatment that was planned for 1,033 of those at baseline was monitoring (oral hygiene instruction, applying or prescribing fluoride or varnish, or both), and the remaining 308 received a sealant (n = 192) or invasive therapy (n = 116). At the 20-month visit, clinicians continued to monitor 927 (90 percent) of the 1,033 monitored lesions. Clinicians decided to seal 61 (6 percent) of the 1,033 lesions (mean follow-up, 19 months) and invasively treat 45 (4 percent) of them (mean follow-up, 15 months). Young patient age (< 18 years) (odds ratio = 3.4; 95 percent confidence interval, 1.7-6.8) and the lesion's being on a molar (odds ratio = 1.8; 95 percent confidence interval, 1.3-2.6) were associated with the clinician's deciding at some point after follow-up to seal the lesion or treat it invasively.

CONCLUSIONS

Almost all (90 percent) QOC lesions for which the treatment planned at baseline was monitoring still were planned to undergo monitoring after 20 months. This finding suggests that noninvasive management is appropriate for these lesions.

PRACTICAL IMPLICATIONS

Previous study results from baseline indicated a high prevalence of QOC lesions (34 percent). Clinicians should consider long-term monitoring when making treatment decisions about these lesions.

Prefrontal cortex white matter tracts in prodromal Huntington disease

Huntington disease (HD) is most widely known for its selective degeneration of striatal neurons but there is also growing evidence for white matter (WM) deterioration. The primary objective of this research was to conduct a large-scale analysis using multisite diffusion-weighted imaging (DWI) tractography data to quantify diffusivity properties along major prefrontal cortex WM tracts in prodromal HD. Fifteen international sites participating in the PREDICT-HD study collected imaging and neuropsychological data on gene-positive HD participants without a clinical diagnosis (i.e., prodromal) and gene-negative control participants. The anatomical prefrontal WM tracts of the corpus callosum (PFCC), anterior thalamic radiations (ATRs), inferior fronto-occipital fasciculi (IFO), and uncinate fasciculi (UNC) were identified using streamline tractography of DWI. Within each of these tracts, tensor scalars for fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity coefficients were calculated. We divided prodromal HD subjects into three CAG-age product (CAP) groups having Low, Medium, or High probabilities of onset indexed by genetic exposure. We observed significant differences in WM properties for each of the four anatomical tracts for the High CAP group in comparison to controls. Additionally, the Medium CAP group presented differences in the ATR and IFO in comparison to controls. Furthermore, WM alterations in the PFCC, ATR, and IFO showed robust associations with neuropsychological measures of executive functioning. These results suggest long-range tracts essential for cross-region information transfer show early vulnerability in HD and may explain cognitive problems often present in the prodromal stage. Hum Brain Mapp 36:3717-3732, 2015. © 2015 Wiley Periodicals, Inc.

Gradient nonlinearity correction to improve apparent diffusion coefficient accuracy and standardization in the american college of radiology imaging network 6698 breast cancer trial

PURPOSE

To evaluate a gradient nonlinearity correction (GNC) program for quantitative apparent diffusion coefficient (ADC) measurements on phantom and human subject diffusion-weighted (DW) magnetic resonance imaging (MRI) scans in a multicenter breast cancer treatment response study

MATERIALS AND METHODS

A GNC program using fifth-order spherical harmonics for gradient modeling was applied retrospectively to qualification phantom and human subject scans. Ice-water phantoms of known diffusion coefficient were scanned at five different study centers with different scanners and receiver coils. Human in vivo data consisted of baseline and early-treatment exams on 54 patients from four sites. ADC maps were generated with and without GNC. Regions of interest were defined to quantify absolute errors and changes with GNC over breast imaging positions.

RESULTS

Phantom ADC errors varied with region of interest (ROI) position and scanner configuration; the mean error by configuration ranged from 1.4% to 19.9%. GNC significantly reduced the overall mean error for all sites from 9.9% to 0.6% (P = 0.016). Spatial dependence of GNC was highest in the right-left (RL) and anterior-posterior (AP) directions. Human subject mean tumor ADC was reduced 0.2 to 12% by GNC at different sites. By regression, every 1-cm change in tumor ROI position between baseline and follow-up visits resulted in an estimated change of 2.4% in the ADC early-treatment response measurement.

CONCLUSION

GNC is effective for removing large, system-dependent errors in quantitative breast DWI. GNC may be important in ensuring reproducibility in multicenter studies and in reducing errors in longitudinal treatment response measures arising from spatial variations in tumor position between visits.

Review of multicenter studies by multiple institutional review boards: characteristics and outcomes for perinatal studies implemented by a multicenter network

OBJECTIVE

The objective of the study was to describe characteristics and outcomes of a review of multisite perinatal studies by individual institutional review boards (IRBs) and identify barriers and opportunities for streamlined IRB review.

STUDY DESIGN

We compared the review of 5 collaborative protocols by individual IRBs at National Perinatal Research Consortium centers from 2007 through 2012. Three randomized trials, 1 observational study, and 1 follow-up study of a trial were selected. IRB logs and communications were reviewed and abstracted by trained team members.

RESULTS

Seven or 8 IRBs reviewed each protocol. Monthly IRB meeting frequency varied from 1 to 6. Full board review was required by all IRBs for the primary trials but not by all for the observational protocols. The overall duration from submission to approval (P = .024) and number of stipulations (P = .007) differed across protocols but not across IRBs. However, times from submission-to-IRB review (P = .011) and IRB review-to-initial letter (P < .007) differed across sites. Both overall submission-to-approval and initial review-to-approval times increased with the increasing number of IRB review stipulations (both values P < .001). Significant delays (>60 days) were few and not consistent across IRBs or protocols. Most stipulations were stylistic or editorial modifications rather than regulatory requests. All protocols were approved without changes, and no more than 1 IRB meeting was needed at each site.

CONCLUSION

Findings confirm unnecessary duplication and variability and some similarities in IRB review processes and outcomes for multisite perinatal studies. This may help guide initiatives to streamline IRB review and reduce research delays and burdens.

Multivendor implementation and comparison of volumetric whole-brain echo-planar MR spectroscopic imaging

PURPOSE

To assess volumetric proton MR spectroscopic imaging (MRSI) of the human brain on multivendor MRI instruments.

METHODS

Echo-planar spectroscopic imaging was developed on instruments from three manufacturers, with matched specifications and acquisition protocols that accounted for differences in sampling performance, radiofrequency (RF) power, and data formats. Intersite reproducibility was evaluated for signal-normalized maps of N-acetylaspartate (NAA), creatine (Cre), and choline using phantom and human subject measurements. Comparative analyses included metrics for spectral quality, spatial coverage, and mean values in atlas-registered brain regions.

RESULTS

Intersite differences for phantom measurements were less than 1.7% for individual metabolites and less than 0.2% for ratio measurements. Spatial uniformity ranged from 79% to 91%. The human studies found differences of mean values in the temporal lobe, but good agreement in other white matter regions, with maximum differences relative to their mean of under 3.2%. For NAA/Cre, the maximum difference was 1.8%. In gray matter, a significant difference was observed for frontal lobe NAA. Primary causes of intersite differences were attributed to shim quality, B0 drift, and accuracy of RF excitation. Correlation coefficients for measurements at each site were over 0.60, indicating good reliability.

CONCLUSION

A volumetric intensity-normalized MRSI acquisition can be implemented in a comparable manner across multivendor MR instruments.

Comprehensive assessment and standardization of solid phase multiplex-bead arrays for the detection of antibodies to HLA

Solid phase multiplex-bead arrays for the detection and characterization of HLA antibodies provide increased sensitivity and specificity compared to conventional lymphocyte-based assays. Assay variability due to inconsistencies in commercial kits and differences in standard operating procedures (SOP) hamper comparison of results between laboratories. The Clinical Trials in Organ Transplantation Antibody Core Laboratories investigated sources of assay variation and determined if reproducibility improved through utilization of SOP, common reagents and normalization algorithms. Ten commercial kits from two manufacturers were assessed in each of seven laboratories using 20 HLA reference sera. Implementation of a standardized (vs. a nonstandardized) operating procedure greatly reduced MFI variation from 62% to 25%. Although laboratory agreements exceeded 90% (R(2) ), small systematic differences were observed suggesting center specific factors still contribute to variation. MFI varied according to manufacturer, kit, bead type and lot. ROC analyses showed excellent consistency in antibody assignments between manufacturers (AUC > 0.9) and suggested optimal cutoffs from 1000 to 1500 MFI. Global normalization further reduced MFI variation to levels near 20%. Standardization and normalization of solid phase HLA antibody tests will enable comparison of data across laboratories for clinical trials and diagnostic testing.

Use of methylphenidate for the management of fatigue in Chinese patients with cancer

REASON FOR THE STUDY: Studies on methylphenidate for cancer-related fatigue showed conflicting results. This prospective study aims to determine whether methylphenidate is useful for relieving fatigue in Chinese patients with cancer. Chinese Version of Brief Fatigue Inventory (BFI-C) was administered on days 1, 8, and 29. Methylphenidate dose on day 1 was 5 mg daily then adjusted after day 8 according to response and side effects tolerance.

MAIN FINDINGS

Only 48% of the 25 recruited patients were on methylphenidate by day 29. Overall, no significant improvement in fatigue level was observed after methylphenidate, though benefits were shown in subgroups with age ≤ 65 and higher baseline BFI-C values.

PRINCIPAL CONCLUSIONS

Methylphenidate may be useful for management of cancer-related fatigue in selected Chinese patients.

Lessons learned during the conduct of clinical studies in the dental PBRN

Effectively addressing challenges of conducting research in nonacademic settings is crucial to its success. A dental practice-based research network called The Dental Practice-Based Research Network (DPBRN) is comprised of practitioner- investigators in two health maintenance organizations, several universities, many U.S. states, and three Scandinavian countries. Our objective in this article is to describe lessons learned from conducting studies in this research context; the studies are conducted by clinicians in community settings who may be doing their first research study. To date, twenty-one studies have been completed or are in implementation. These include a broad range of topic areas, enrollment sizes, and study designs. A total of 1,126 practitioner-investigators have participated in at least one study. After excluding one study because it involved electronic records queries only, these studies included more than 70,000 patient/participant units. Because the DPBRN is committed to being both practitioner- and patient-driven, all studies must be approved by its Executive Committee and a formal study section of academic clinical scientists. As a result of interacting with a diverse range of institutional and regulatory entities, funding agencies, practitioners, clinic staff, patients, academic scientists, and geographic areas, twenty-three key lessons have been learned. Patients' acceptance of these studies has been very high, judging from high participation rates and their completion of data forms. Early studies substantially informed later studies with regard to study design, practicality, forms design, informed consent process, and training and monitoring methods. Although time-intensive and complex, these solutions improved acceptability of practice-based research to patients, practitioners, and university researchers.

Informative value of Patient Reported Outcomes (PRO) in Health Technology Assessment (HTA)

Background

“Patient-Reported Outcome” (PRO) is used as an umbrella term for different concepts for measuring subjectively perceived health status e. g. as treatment effects. Their common characteristic is, that the appraisal of the health status is reported by the patient himself. In order to describe the informative value of PRO in Health Technology Assessment (HTA) first an overview of concepts, classifications and methods of measurement is given. The overview is complemented by an empirical analysis of clinical trials and HTA-reports on rheumatoid arthritis and breast cancer in order to report on type, frequency and consequences of PRO used in these documents.

Methods

For both issues systematic reviews of the literature have been performed. The search for methodological literature covers the publication period from 1990 to 2009, the search for clinical trials of rheumatoid arthritis and breast cancer covers the period 2005 to 2009. Both searches were performed in the medical databases of the German Institute of Medical Documentation and Information (DIMDI). The search for HTA-reports and methodological papers of HTA-agencies was performed in the CRD-Databases (CRD = Centre for Reviews and Dissemination) and by handsearching the websites of INAHTA member agencies (INAHTA = International Network of Agencies for Health Technology Assessment). For all issues specific inclusion and exclusion criteria were defined. The methodological quality of randomized controlled trials (RCT) was assessed by a modified version of the Cochrane Risk of Bias Tool. For the methodological part information extraction from the literature is structured by the report’s chapters, for the empirical part data extraction sheets were constructed. All information is summarized in a qualitative manner.

Results

Concerning the methodological issues the literature search retrieved 158 documents (87 documents related to definition or classification, 125 documents related to operationalisation of PRO). For the empirical analyses 225 RCT (rheumatoid arthritis: 77; breast cancer: 148) and 40 HTA-reports and method papers were found.

The analysis of the methodological literature confirms the role of PRO as an umbrella term for a variety of different concepts. The newest classification system facilitates the description of PRO measures by construct, target population and the method of measurement. Steps of operationalisation involve defining a conceptual framework, instrument development, exploration of measurement properties or, possibly, the modification of existing instruments.

Seven out of 59 RCT analysing the effects of antibody therapy for rheumatoid arthritis define PRO as the primary endpoint, 38 trials utilize composite measures (ACR, DAS) and ten trials report clinical or radiological parameters as the primary endpoint. Six out of 123 chemotherapy trials for breast cancer define PRO as the primary endpoint, while 98 trials report clinical endpoints (survival, tumour response, progression) in their primary analyses. Discrepancies in the number of trials result from inaccurate specifications of endpoints in the publications. This distribution is reflected in the HTA-reports: while almost all reports on rheumatoid arthritis refer to PRO, this is only the case in about half of the reports on breast cancer.

Conclusions

As definition and classification of PRO are concerned, coherent concepts are found in the literature. Their operationalisation and implementation must be guided by scientific principles. The type and frequency of PRO used in clinical trials largely depend on the disease analysed. The HTA-community seems to pursue the utilization of PRO proactively – in case of missing data the need for further research is stated.

Reader variability in the use of diagnostic terms to describe white matter lesions seen on cranial scans of severely premature infants: the ELGAN study

PURPOSE

To evaluate reader variability of white matter lesions seen on cranial sonographic scans of extreme low gestational age neonates (ELGANs).

METHODS

In 1,452 ELGANs, cranial sonographic scans were obtained in the first and second postnatal weeks, and between the third postnatal week and term. All sets of scans were read independently by two sonologists. We reviewed the use of four diagnostic labels: early periventricular leucomalacia, cystic periventricular leucomalacia, periventricular hemorrhagic infarction (PVHI), and other white matter diagnosis, by 16 sonologists at 14 institutions. We evaluated the association of these labels with location and laterality of hyperechoic and hypoechoic lesions, location of intraventricular hemorrhage, and characteristics of ventricular enlargement.

RESULTS

Experienced sonologists differed substantially in their application of the diagnostic labels. Three readers applied early periventricular leucomalacia to more than one fourth of all the scans they read, whereas eight applied this label to ≤5% of scans. Five applied PVHI to ≥10% of scans, while three applied this label to ≤5% of scans. More than one third of scans labeled cystic periventricular leucomalacia had unilateral hypoechoic lesions. White matter abnormalities in PVHI were more extensive than in periventricular leucomalacia and were more anteriorly located. Hypoechoic lesions on late scans tended to be in the same locations, regardless of the diagnostic label applied.

CONCLUSIONS

Experienced sonologists differ considerably in their tendency to apply diagnostic labels for white matter lesions. This is due to lack of universally agreed-upon definitions. We recommend reducing this variability to improve the validity of large multicenter studies.

Assessing immunophenotyping performance: proficiency-validation for adopting improved flow cytometry methods

BACKGROUND

The continuous improvement and evolution of immune cell phenotyping requires periodic upgrading of laboratory methods and technology. Flow cytometry laboratories that are participating in research protocols sponsored by the NIAID are required to perform "switch" studies to validate performance before methods for T-cell subset analysis can be changed.

METHODS

Switch studies were conducted among the four flow cytometry laboratories of the Multicenter AIDS Cohort Study (MACS), comparing a 2-color, lyse-wash method and a newer, 3-color, lyse no-wash method. Two of the laboratories twice failed to satisfy the criteria for acceptable differences from the previous method. Rather than repeating more switch studies, these laboratories were allowed to adopt the 3-color, lyse no-wash method. To evaluate the impact of the switch to the new method at these two sites, their results with the new method were evaluated within the context of all laboratories participating in the NIH-NIAID-Division of AIDS Immunology Quality Assurance (IQA) proficiency-testing program.

RESULTS

Laboratory performance at these two sites substantially improved relative to the IQA standard test results. Variation across the four MACS sites and across replicate samples was also reduced.

CONCLUSIONS

Although switch studies are the conventional method for assessing comparability of laboratory methods, two alternatives to the requirement of repeating failed switch studies should be considered: (1) test the new method and assess performance on the proficiency testing reference panel, and (2) prior to adoption of the new methods, use both the old and the new method on the reference panel samples and demonstrate that performance with the new method is better according to standard statistical procedures. These alternatives may help some laboratories' transition to a new and superior methodology more quickly than if they are required to attempt multiple, serial switch studies.

Impact of institutional review board practice variation on observational health services research

OBJECTIVE

To describe, qualitatively and quantitatively, the impact of a review by multiple institutional review boards (IRBs) on the conduct of a multisite observational health services research study. DATA SOURCE AND SETTING: Primary data collection during 2002, 2003, and 2004 at 43 United States Department of Veterans Affairs (VA) primary care clinics.

DESIGN

Explanatory sequential mixed methods design incorporating qualitative and quantitative elements in sequence. DATA COLLECTION AND ABSTRACTION METHODS: Field notes and documents collected by research staff during a multisite observational health services research study were used in thematic analysis. Themes were quantified descriptively and merged with timeline data.

PRINCIPAL FINDINGS

Approximately 4,680 hours of staff time over a 19-month period were devoted solely to the IRB process. Four categories of phenomena impacting research were observed: (1) Recruitment, retention, and communication issues with local site principal investigators (PIs). Local PIs had no real role but were required by IRBs. Twenty-one percent of sites experienced turnover in local PIs, and local PI issues added significant delay to most sites. (2) Wide variation in standards applied to review and approval of IRB applications. The study was designed to be qualified under U.S. government regulations for expedited review. One site exempted it from review (although it did not qualify for exemption), 10 granted expedited review, 31 required full review, and one rejected it as being too risky to be permitted. Twenty-three required inapplicable sections in the consent form and five required HIPAA (Health Insurance Portability and Accountability Act of 1996) consent from physicians although no health information was asked of them. Twelve sites requested, and two insisted upon, provisions that directly increased the risk to participants. (3) Multiple returns for revision of IRB applications, consent documents, and ancillary forms. Seventy-six percent of sites required at least one resubmission, and 15 percent of sites required three or more (up to six) resubmissions. Only 12 percent of sites required any procedural or substantive revision; most resubmissions were editorial changes to the wording of the consent document. (4) Process failures (long turnaround times, lost paperwork, difficulty in obtaining necessary forms, unavailability of key personnel at IRBs). The process required from 52 to 798 (median 286) days to obtain approval at each site.

CONCLUSIONS

Several features of the IRB system as currently configured impose costly burdens of administrative activity and delay on observational health services research studies, and paradoxically decrease protection of human subjects. Central review with local opt-out, cooperative review, or a system of peer review could reduce costs and improve protection of human subjects.

A multi-center study for birth defect monitoring systems in Korea

The aim of this study was to establish a multi-center birth defects monitoring system to evaluate the prevalence and the serial occurrence of birth defects in Korea. Ten medical centers participated in this program. A trained nurse collected relevant records from delivery units and pediatric clinics in participating hospitals on a monthly basis. We observed 1,537 cases of birth defects among 86,622 deliveries, which included live births and stillbirths. The prevalence of birth defects was 1.8%, and the sex distribution of the birth defect cases was 55.2% male and 41.6% female. The highest proportion of birth defects was in the cardiovascular system (17.5%), followed by birth defects involving in the genitourinary system (15.6%). Chromosomal anomalies were detected 30.0 per 10,000 births. Of these chromosomal anomalies, Down syndrome was most frequently observed. This study led to an establishment of a multi-center active monitoring system for birth defects. To better understand the serial occurrence of birth defects in Korea, it is necessary to increase the number of participating hospitals and to launch on a nation-wide multi-center study.

Thrombolytic therapy for acute myocardial infarction. Lessons to be learned

Trials of thrombolytic therapy have taught us that 1) lysis of hemostatic plugs, not fibrinogenolysis, is the major cause of bleeding complications; 2) as currently reported, patency rates 90 minutes after the onset of therapy are both meaningless and misleading as surrogate end-points for either myocardial salvage or reduced mortality; 3) extensive restoration of myocardial function requires much earlier administration of thrombolytic therapy than is currently the practice; 4) reduced mortality can be demonstrated well after the period in which myocardial salvage can be shown; and 5) drug development based on fibrin specificity is probably an obsolete concept, because therapy with a fibrin-specific agent such as recombinant tissue-type plasminogen activator does not enhance safety and is associated with a high degree of rethrombosis.