Associations between psychological flexibility and mental health problems during the Covid-19 pandemic: a three-level meta-analytic review

Many studies have indicated the negative associations between psychological flexibility (PF) and mental health problems (i.e., depressive, anxiety, and stress symptoms) during the COVID-19 pandemic, however, the associations revealed were inconsistent. This study aimed to summarize the primary literature quantitatively and provide better estimates of these associations. A systematic literature review was performed in six databases (finally yielding twenty-four studies) and three-level meta-analytic models were employed to synthesize effect sizes and to examine potential moderators of the associations between PF and depressive, anxiety, and stress symptoms. Our metaanalyses results revealed a moderate and significant association between PF and depressive (r =  − 0.458, 95% CI [− 0.594; − 0.323], p