The Role of Multiple Imputation in Noninferiority Trials for Binary Outcomes

We consider the role of multiple imputation (MI) when analyzing noninferiority (NI) clinical trials with missing data. When the endpoint is measured longitudinally, direct-likelihood methods can be used. In this article, the focus is on the situation in which the endpoint is not measured longitudinally but other relevant data are measured at or after baseline prior to planned collection of the primary endpoint data. Simulation results are presented for various scenarios based on the missingness mechanism, the dropout rate, and the size of NI margin. When the endpoint is binary, the ratio of the amount of missing data to the noninferiority margin will affect the operating characteristics of any analysis strategy (whether imputation based or not), an issue that is unique to noninferiority trials. Biased estimates of treatment effect under missingness, not completely at random, may arise when using a misspecified imputation model lacking treatment effect, resulting in substantially inflated Type I error rates in noninferiority trials by making the two groups appear more similar, opposite the usual impact in superiority trials. As in superiority trials, MI will have most benefit when data are missing at random, and the important predictor variables are included in the imputation model.     

Gaining and maintaining recognition as a paediatric postgraduate trainer

Consultants who act as Educational or Clinical Supervisors to postgraduate doctors must now be recognised as trainers by the GMC. This is a formal process conducted at employer level using supporting information against domains formulated by the Academy of Medical Educators. Recognition is recommended to Health Education England and reported to the GMC. This article addresses how paediatricians in the UK can gain recognition as a trainer of foundation doctors and specialty trainees in paediatrics and how to maintain that recognition over the 5-year cycle.     

Reliability of a two‐colour chewing gum test to assess masticatory performance in complete denture wearers

The aim of this study was to test the reliability of a method to measure the masticatory performance of complete denture wearers employing a colour‐mixing ability test and assessment by visual and electronic colourimetric analysis. A sample of 75 subjects was selected from patients who received new conventional complete dentures. Masticatory tests were performed using a two‐colour chewing gum that was masticated for 5, 10, 20, 30 and 50 chewing cycles, performed in a random order. The mixing level of the two colours of the chewed gum was assessed visually by two independent raters based on a 5‐point ordinal scale. The specimens were flattened into a 1‐mm‐width wafer, scanned and saved as a two‐sided digital image. Each pair of images was submitted to an electronic colourimetric analysis to assess the level of colour mixture, measured by the circular variance of hue (VOH ). Overall inter‐ and intra‐rater agreements in visual analysis were 64% and 68%, respectively (almost 99% of scores ranged within ±1 point), whilst overall weighted kappa was >0.80. A proportional increase in the level of mixture occurred with increased number of chewing cycles (P  < .001). Similarly, VOH and the visual analysis were highly correlated (r = ?.89; P  < .001). Bland‐Altman plots revealed excellent agreement and extremely low systematic error between duplicated VOH measures. It was concluded that the two‐colour chewing gum test is a reliable method to assess the masticatory performance in complete denture wearers using both visual and electronic colourimetric analyses.     

The Action Research Program: Experiential Learning in Systems-Based Practice for First-Year Medical Students

Problem: Systems-based practice focuses on the organization, financing, and delivery of medical services. The American Association of Medical Colleges has recommended that systems-based practice be incorporated into medical schools’ curricula. However, experiential learning in systems-based practice, including practical strategies to improve the quality and efficiency of clinical care, is often absent from or inconsistently included in medical education. Intervention: A multidisciplinary clinician and nonclinician faculty team partnered with a cardiology outpatient clinic to design a 9-month clerkship for 1st-year medical students focused on systems-based practice, delivery of clinical care, and strategies to improve the quality and efficiency of clinical operations. The clerkship was called the Action Research Program. In 2013–2014, 8 trainees participated in educational seminars, research activities, and 9-week clinic rotations. A qualitative process and outcome evaluation drew on interviews with students, clinic staff, and supervising physicians, as well as students’ detailed field notes. Context: The Action Research Program was developed and implemented at the University of California, San Francisco, an academic medical center in the United States. All educational activities took place at the university's medical school and at the medical center's cardiology outpatient clinic. Outcome: Students reported and demonstrated increased understanding of how care delivery systems work, improved clinical skills, growing confidence in interactions with patients, and appreciation for patients’ experiences. Clinicians reported increased efficiency at the clinic level and improved performance and job satisfaction among medical assistants as a result of their unprecedented mentoring role with students. Some clinicians felt burdened when students shadowed them and asked questions during interactions with patients. Most student-led improvement projects were not fully implemented. Lessons Learned: The Action Research Program is a small pilot project that demonstrates an innovative pairing of experiential and didactic training in systems-based practice. Lessons learned include the need for dedicated time and faculty support for students’ improvement projects, which were the least successful aspect of the program. We recommend that future projects aiming to combine clinical training and quality improvement projects designate distinct blocks of time for trainees to pursue each of these activities independently. In 2014–2015, the University of California, San Francisco School of Medicine incorporated key features of the Action Research Program into the standard curriculum, with plans to build upon this foundation in future curricular innovations.     

脂蛋白（a）和胱抑素C联合检测在2型糖尿病中的临床应用效果分析

目的：对胱抑素C和脂蛋白（ a）在2型糖尿病临床诊断治疗中的价值进行分析探讨。方法：对我院收治的2型糖尿病患者和体检中心选取的正常组进行胱抑素C和脂蛋白（ a）检验，采用免疫比浊法进行检测，并将2组检验结果进行比较，分析2组检验结果之间的差异，概括两者在2型糖尿病诊断治疗中的价值。结果：观察组的胱抑素C水平和脂蛋白（ a）水平与健康组之间存在明显差异，其胱抑素C和脂蛋白（a）水平均明显高于健康组，p＜0．05，且胱抑素C与脂蛋白（a）之间呈正相关关系。结论：糖尿病患者的胱抑素C和脂蛋白（ a）水平明显高于正常健康人群，是2型糖尿病临床诊断治疗的重要指标，对其进行联合检测能够有效监测糖尿病发展，预防和控制并发症发生。