Tests for 2 x 2 Tables in Clinical Trials

Five standard tests are compared: chi-squared, Fisher\u27s exact, Yates’ correction, Fisher’s exact mid-p, and Barnard’s. Yates’ is always inferior to Fisher’s exact. Fisher’s exact is so conservative that one should look for alternatives. For certain sample sizes, Fisher’s mid-p or Barnard’s test maintain the nominal alpha and have superior power

Use of implantable cardioverter-defibrillators for primary prevention in older patients: A systematic literature review and meta-analysis

Background: Randomized clinical trials (RCTs) have demonstrated the efficacy of implantable cardioverter-defibrillators (ICDs) in reducing sudden cardiac death (SCD) in specific patient populations. However, patients ≥ 65 years were under-represented in these trials and the overall benefit of ICDs may be diminished in older patients due to competing risks for death. We evaluate the published data on ICD efficacy at reducing all-cause mortality in patients ≥ 65 years and in patients ≥ 75 years. Methods: We searched MEDLINE to identify RCTs and observational studies of ICDs that provided age-based outcome data for primary prevention of SCD. The primary endpoint was mortality evaluated by a meta-analysis of the RCTs using a random-effects model. Secondary endpoints included operative mortality, long-term complications and quality of life. Results: The enrollment of patients ≥ 65 years in RCTs was limited (range: 33% in DEFINITE to 56% in MUSTT). Combining data from four RCTs (n = 3,562) revealed that primary prevention ICD therapy is efficacious in reducing all-cause mortality in patients ≥ 65 years (HR 0.66; 95% CI 0.50–0.87; test of heterogeneity: X2 = 5.26; p = 0.15). For patients ≥ 75 years, combining data from four RCTs (n = 579) revealed that primary prevention ICD therapy remains efficacious in reducing all-cause mortality (HR 0.73; 95% CI 0.51–0.974; p = 0.03). There appears to be no difference in ICD-related, operative, in-hospital, or long- -term complications among older patients compared to younger patients, although it remains unclear if older patients have a better quality of life with an ICD than younger patients. Conclusions: Although the overall evidence regarding ICD efficacy in patients ≥ 65 years is limited and divergent, and the evidence available for patients ≥ 75 years is even more sparse, our meta-analysis suggests that primary prevention ICDs may be beneficial in older patients. Our findings need to be validated by future studies, particularly ones examining ICD complications and quality of life. (Cardiol J 2011; 18, 5: 503–514

In or out? Methodological considerations for including and excluding findings from a meta-analysis of predictors of antiretroviral adherence in HIV-positive women

This paper is a discussion detailing the decisions concerning whether to include or exclude findings from a meta-analysis of report of quantitative studies of antiretroviral adherence in HIV-positive women

Making Sense of Qualitative and Quantitative Findings in Mixed Research Synthesis Studies

The synthesis of qualitative and quantitative research findings is increasingly promoted, but many of the conceptual and methodological issues it raises have yet to be fully understood and resolved. In this article, we describe how we handled issues encountered in efforts to synthesize the findings in forty-two reports of studies of antiretroviral adherence in HIV-positive women in the course of an ongoing study to develop methods to synthesize qualitative and quantitative research findings in common domains of health-related research. Working with these reports underscored the importance of looking past method claims and ideals and directly at the findings themselves, differentiating between aggregative syntheses in which findings are assimilated and interpretive syntheses in which they are configured, and understanding the judgments involved in designating relationships between findings as confirmatory, divergent, or complementary