Browsing by Author "Pulkkinen, Tero"

Publication bias is one of the central threats to the validity of scientific research. In research of mindfulness-based interventions publication bias has been examined mostly in meta-analyses with statistical methods that have several limitations. This study examined how meta-analyses and systematic reviews that have examined publication bias have succeeded in their assessments. A rough estimate of publication bias and suggestions for further meta-analyses were made based on the examination. The study was conducted in the form of a literature review. It was found that there are significant limitations in examinations of publication bias, the most central of which being limited sample sizes, strong heterogeneity of studies and suboptimal method choices in meta-analyses and systematic reviews. The conclusions about publication bias also seemed overly optimistic in some cases. These limitations made it difficult to estimate the magnitude of publication bias. Regardless of that, there was evidence for the existence of publication bias, although in general it did not seem to lower the effect sizes of mindfulness-based interventions to zero. In future, publication bias should be assessed with methods less sensitive to the issues raised in this study. In addition, there is a need for pre-registered, good-quality replication studies of mindfulness-based interventions.