EFFECTS OF MINDFULNESS-BASED INTERVENTIONS ON DISRUPTIVE BEHAVIOR: A META-ANALYSIS OF SINGLE-CASE RESEARCH : Effects of Mindfulness-Based Interventions

Recently, the psychological construct mindfulness has received a great deal of attention. The majority of research has focused on clinical studies to evaluate the efficacy of mindfulness-based interventions. This line of research has led to promising data suggesting mindfulness-based interventions are effective for treatment of both psychological and physical symptoms. However, an equally important direction for future research is to investigate questions concerning mechanisms of action underlying mindfulness-based interventions. This theoretical paper proposes a model of mindfulness, in an effort to elucidate potential mechanisms to explain how mindfulness affects positive change. Potential implications and future directions for the empirical study of mechanisms involved in mindfulness are addressed. Copyright (c) 2005 Wiley Periodicals, Inc.

The explanation of heterogeneity plays an important role in meta-analysis. The random effects meta-regression model allows the inclusion of trial-specific covariates which may explain a part of the heterogeneity. We examine the commonly used tests on the parameters in the random effects meta-regression with one covariate and propose some new test statistics based on an improved estimator of the variance of the parameter estimates. The approximation of the distribution of the newly proposed tests is based on some theoretical considerations. Moreover, the newly proposed tests can easily be extended to the case of more than one covariate. In a simulation study, we compare the tests with regard to their actual significance level and we consider the log relative risk as the parameter of interest. Our simulation study reflects the meta-analysis of the efficacy of a vaccine for the prevention of tuberculosis originally discussed in Berkey et al. The simulation study shows that the newly proposed tests are superior to the commonly used test in holding the nominal significance level. Copyright 2003 John Wiley & Sons, Ltd.