Implications of a “null” randomized controlled trial of mindfulness and compassion interventions in healthy adults

Objective: Extensive research suggests that short-term meditation interventions may hold therapeutic promise for a wide range of psychosocial outcomes. In response to calls to subject these interventions to more methodologically rigorous tests, a randomized controlled trial tested the effectiveness of a mindfulness meditation intervention and a compassion meditation intervention against an active control in a sample of demographically diverse, medically and psychiatrically healthy adults. Methods: Two hundred and four participants completed a battery of questionnaires to assess psychological experience, participated in a laboratory stress test to measure their biological stress reactivity, and wore the Electronically Activated Recorder (EAR) to assess daily behaviors before and after an eight-week intervention (mindfulness meditation intervention, compassion meditation intervention, or health education discussion group). Results: Neither meditation intervention reliably impacted participants’ subjective experience, biological stress reactivity, or objectively assessed daily behaviors. Further, post-hoc moderation analyses found that neither baseline distress nor intervention engagement significantly moderated the effects. Conclusion: Results from this trial – which was methodologically rigorous and powered to detect all but small effects – were essentially null. These results are an important data point for the body of research about meditation interventions. Implications of these non-significant effects are discussed in the context of prior studies, and future directions for contemplative intervention research are recommended.