Our analyses are consistent with the hypothesis that low vitamin D concentration is associated with depression, and highlight the need for randomised controlled trials of vitamin D for the prevention and treatment of depression to determine whether this association is causal.

BackgroundSensitivity analyses play a crucial role in assessing the robustness of the findings or conclusions based on primary analyses of data in clinical trials. They are a critical way to assess the impact, effect or influence of key assumptions or variations—such as different methods of analysis, definitions of outcomes, protocol deviations, missing data, and outliers—on the overall conclusions of a study.The current paper is the second in a series of tutorial-type manuscripts intended to discuss and clarify aspects related to key methodological issues in the design and analysis of clinical trials.DiscussionIn this paper we will provide a detailed exploration of the key aspects of sensitivity analyses including: 1) what sensitivity analyses are, why they are needed, and how often they are used in practice; 2) the different types of sensitivity analyses that one can do, with examples from the literature; 3) some frequently asked questions about sensitivity analyses; and 4) some suggestions on how to report the results of sensitivity analyses in clinical trials.SummaryWhen reporting on a clinical trial, we recommend including planned or posthoc sensitivity analyses, the corresponding rationale and results along with the discussion of the consequences of these analyses on the overall findings of the study.

There is insufficient evidence to support the efficacy of Vit D supplementation in depression symptoms, and more RCTs using depressed patients are warranted.

Introduction:Despite its efficacy and widespread use, methadone maintenance treatment (MMT) continues to be widely stigmatized. Reducing the stigma surrounding MMT will help improve the accessibility, retention, and treatment outcomes in MMT.Methods:Semi-structured interviews were conducted with 18 adults undergoing MMT. Thematic content analysis was used to identify overarching themes.Results:In total, 78% of participants reported having experienced stigma surrounding MMT. Common stereotypes associated with MMT patients included the following: methadone as a way to get high, incompetence, untrustworthiness, lack of willpower, and heroin junkies. Participants reported that stigma resulted in lower self-esteem; relationship conflicts; reluctance to initiate, access, or continue MMT; and distrust toward the health care system. Public awareness campaigns, education of health care workers, family therapy, and community meetings were cited as potential stigma-reduction strategies.Discussion and Conclusion:Stigma is a widespread and serious issue that adversely affects MMT patients’ quality of life and treatment. More efforts are needed to combat MMT-related stigma.