Not all types of meditation are the same: Mediators of change in mindfulness and compassion meditation interventions

•Comparison of mindfulness (MBSR) and compassion (CCT) programs.•Both programs had a similar effectiveness on distress and well-being.•MBSR was mediated by changes in present-moment awareness mechanisms.•CCT was mediated by changes in prosocial and emotional mechanisms.•Meditation type matters: similar results through different pathways. The general aim of the study was to examine the relative effectiveness and mediators of change in standardized mindfulness and compassion interventions. A sample of 431 participants enrolled in a Mindfulness-Based Stress Reduction program (MBSR = 277) and a Compassion Cultivation Training (CCT = 154). The assessment before and after the program included a set of outcomes and mediators measures. A three-step data analysis plan was followed: ANCOVAs, Reliable Change Index, and mediations (simple and multiple). Both interventions yielded increased mindfulness, decentering, body awareness, and self-compassion. Yet, present-moment awareness improvements (i.e., decentering, and body awareness) were significantly larger in the MBSR than in CCT, whereas socio-emotional changes (i.e., common humanity and empathic concern) were larger in the CCT than in MBSR. The magnitude of effect sizes ranged from medium to large. Furthermore, both mindfulness and compassion interventions yielded similar changes in psychological distress (i.e., stress, anxiety, and depression), maladaptive cognitive processes (i.e., rumination and thought suppression), and well-being. The mediation models showed that although the MBSR program seemingly relies on changes in present-moment awareness mechanisms (i.e., decentering and body awareness) to reduce psychological distress and to improve well-being, the CCT program seemingly achieves the same positive outcomes through changes in socio-emotional mechanisms (i.e., common-humanity and empathy concern). Due to our naturalistic design in real-world community setting, it was infeasible to randomly assign participants to conditions. Our results suggest that mindfulness and compassion programs operate through different pathways to reduce psychological distress and to promote well-being.