Does mindfulness practice promote psychological functioning or is it the other way around? A daily diary study.

Mindfulness-based interventions are commonly used to reduce psychological symptoms and enhance positive qualities of human functioning. However, the influence of mindfulness practice dosage remains poorly understood, limiting dissemination and implementation efforts. The current study examined the association between practice dosage and several constructs related to psychological functioning (positive and negative affect, state mindfulness) over the course of a standardized mindfulness-based intervention (Mindfulness-Oriented Recovery Enhancement). Twenty-five participants completed daily diary assessments for 12 weeks. Two-part gamma regression models examined the dichotomous (did practice occur?) and continuous (how much practice?) components of practice minutes. Practice time and outcomes showed same-day relationships in the expected directions. Lagged models, however, showed no evidence that current day practice time predicts subsequent day outcomes. In contrast, higher current day negative affect predicted less subsequent day practice time, and higher current day mindfulness predicted more subsequent day practice time. In a post hoc analysis, practice time moderated the link between day-to-day affect, strengthening the link for positive affect and weakening the link for negative affect. Collectively, these findings suggest that the causal direction linking practice time and outcome may flow from outcome to practice time, rather than the reverse-with potential recursive relationships between these factors. Further examination of lagged relationships between practice time and outcome as well as random assignment of participants to varying practice dosages (e.g., in within-person microrandomized trials) may help clarify the influence of this central treatment ingredient within mindfulness-based interventions. (PsycInfo Database Record (c) 2020 APA, all rights reserved).