Sections include: experiments and generalised causal inference; statistical conclusion validity and internal validity; construct validity and external validity; quasi-experimental designs that either lack a control group or lack pretest observations on the outcome; quasi-experimental designs that use both control groups and pretests; quasi-experiments: interrupted time-series designs; regresssion discontinuity designs; randomised experiments: rationale, designs, and conditions conducive to doing them; practical problems 1: ethics, participation recruitment and random assignment; practical problems 2: treatment implementation and attrition; generalised causal inference: a grounded theory; (...) generalised causal inference: methods for single studies; generalised causal inference: methods for multiple studies; a critical assessment of our assumptions. (shrink)

Mindfulness as a clinical and nonclinical intervention for a variety of symptoms has recently received a substantial amount of interest. Although the application of mindfulness appears straightforward and its effectiveness is well supported, the concept may easily be misunderstood. This misunderstanding may severely limit the benefit of mindfulness-based interventions. It is therefore necessary to understand that the characteristics of mindfulness are based on a set of seemingly paradoxical structures. This article discusses the underlying paradox by disentangling it into five dialectical (...) positions - activity vs. passivity, wanting vs. non-wanting, changing vs. non-changing, non-judging vs. non-reacting, and active acceptance vs. passive acceptance, respectively. Finally, the practical implications for the medical professional as well as potential caveats are discussed. (shrink)