Bayesian consensus clustering for multivariate longitudinal data

In clinical and epidemiological studies, there is a growing interest in studying the heterogeneity among patients based on longitudinal characteristics to identify subtypes of the study population. Compared to clustering a single longitudinal marker, simultaneously clustering multiple longitudinal markers allow additional information to be incorporated into the clustering process, which reveals co-existing longitudinal patterns and generates deeper biological insight. In the current study, we propose a Bayesian consensus clustering (BCC) model for multivariate longitudinal data. Instead of arriving at a single overall clustering, the proposed model allows each marker to follow marker-specific local clustering and these local clusterings are aggregated to find a global (consensus) clustering. To estimate the posterior distribution of model parameters, a Gibbs sampling algorithm is proposed. We apply our proposed model to the primary biliary cirrhosis study to identify patient subtypes that may be associated with their prognosis. We also perform simulation studies to compare the clustering performance between the proposed model and existing models under several scenarios. The results demonstrate that the proposed BCC model serves as a useful tool for clustering multivariate longitudinal data.     

The 2018 International Consensus Meeting Minor Criteria for Chronic Hip and Knee Periprosthetic Joint Infection: Validation From a Single Center

BackgroundRecently, a revised definition of the minor criteria scoring system for diagnosing periprosthetic joint infection (PJI) was developed by the second International Consensus Meeting on musculoskeletal infection. The new system combines preoperative and intraoperative findings, reportedly achieving high sensitivity and specificity. We aimed to validate the modified scoring system at a high-volume center.MethodsWe retrospectively reviewed patients who underwent a revision total hip or knee arthroplasty at our institution from May 2015 to August 2018. Serum C-reactive protein, synovial white blood cell count and polymorphonuclear percentage, leukocyte esterase test, alpha-defensin, microbiological and histologic results, and documented existence of sinus tract and intraoperative purulence were available for all patients. Cases with at least 1 major criterion were considered as infected. Using the new minor criteria, a score of ≥6 reflects PJI, while a score <3 can be considered as noninfected. Sensitivity, specificity, mean accuracy (ACC), positive predictive value (PPV), and negative predictive value (NPV) were analyzed.ResultsA total of 345 cases were included. A cutoff score of ≥6 points had the following diagnostic performance: area under the curve (AUC) = 0.90; ACC = 0.88; sensitivity = 0.96; specificity = 0.84; PPV = 0.70; NPV = 0.98. Diagnostic performance was better for the hip (AUC = 0.92; ACC = 0.90; sensitivity = 0.96; specificity = 0.86; PPV = 0.81; NPV = 0.98) than the knee (AUC = 0.89; ACC = 0.85; sensitivity = 0.95; specificity = 0.83; PPV = 0.59; NPV = 0.98).ConclusionThe modified scoring system proposed by the 2018 International Consensus Meeting in diagnosing PJI showed high sensitivity and a good performance, especially as rule-out diagnostic criteria. The cutoff level seems to be different between the hip and knee. Further validation studies considering the acknowledged limitations are recommended.     

Measuring the Quality of Hospital-based Domestic Violence Programs

OBJECTIVE: To obtain consensus among a panel of experts on performance measures useful for evaluating the quality of hospital-based domestic violence (DV) programs. METHODS: The Delphi process of consensus development was used with a panel of 18 experts including DV researchers, program planners, and advocates. Three rounds were conducted over a period of six months, with each round involving the completion of a written questionnaire. Panelists were instructed to concentrate on structure and process measures of DV program performance. Health outcome measures were not considered. During each round, panelists rated (scale of 1-5) their level of agreement with each measure, in terms of the measure's usefulness for evaluating hospital-based DV programs. Data were entered into SPSS on a personal computer and frequency distributions, measures of central tendency, and variance were computed for each measure. Consensus development was defined as a reduction in the item-specific variance from one round to the next. RESULTS: A total of 37 performance measures were agreed upon. These measures fell within nine different domains of DV program activities, including: Policies and Procedures, Hospital Physical Environment, Hospital Cultural Environment, Training of Providers, Screening and Safety Assessment, Documentation, Intervention Services, Evaluation Activities, and Collaboration. CONCLUSIONS: A number of measures have been identified as useful for evaluating hospital-based DV programs. Use of these measures should assist researchers, program planners, and administrators in assessing the quality of hospital-based DV programs.     

Photopatch testing: a consensus methodology for Europe

A group of interested European Contact Dermatologists/Photobiologists met to produce a consensus statement on methodology, test materials and interpretation of photopatch testing. While it is recognized that a range of local variables operate throughout Europe, the underlying purpose of the work is to act as an essential preamble to a Pan European Photopatch Test Study focusing particularly on sunscreen chemicals.     

A framework for systematically improving occupational therapy expert opinions on work capacity

Aim:  To present an evidence-based framework to improve the quality of occupational therapy expert opinions on work capacity for litigation, compensation and insurance purposes.
Methods:  Grounded theory methodology was used to collect and analyse data from a sample of 31 participants, comprising 19 occupational therapists, 6 medical specialists and 6 lawyers. A focused semistructured interview was completed with each participant. In addition, 20 participants verified the key findings.
Results:  The framework is contextualised within a medicolegal system requiring increasing expertise. The framework consists of (i) broad professional development strategies and principles, and (ii) specific strategies and principles for improving opinions through reporting and assessment practices.
Conclusions:  The synthesis of the participants' recommendations provides systematic guidelines for improving occupational therapy expert opinion on work capacity.     

Introducing expert systems to medical students using esta, Expert System Teaching Aid

Medical students are allocated little curriculum time for exposure to expert systems. ESTA, a computer model of an expert system, was developed to make best use of this time. The nature of the students' interaction with ESTA is described, and their reactions to the expert system concepts and the place of expert systems in medicine are presented. A discussion of these reactions draws some conclusions about teaching expert systems in particular, and computers in general, in the basic medical course.     

司法鉴定与医学鉴定在医疗服务合同纠纷中运用的比较分析

司法鉴定机构分属公安机关，检察院，人民法院，司法部门，卫生系统和高等院校；医学鉴定机构将属医学会。通过分析司法鉴定与医学复写在医疗服务合同纠纷中的差异，指出了司法鉴定与医学鉴定上冲突所引发的种种忧虑，受司法鉴定与医学鉴定结论冲突而痛苦的医患双方发出同样的声音；界定医疗服务合同纠纷，须在分析司法鉴定与医学鉴定之异同的基础上，认清司法鉴定与医学鉴定之结论的冲突，因为这不仅影响医疗服务合同诉讼之成败，而且更涉及医疗事业之发展，人类健康之大局，消除司法鉴定与医学鉴定条块分割所产生的冲突之关键在于尽快制定统一的《诉讼证据鉴定法》。