The association between social class and the impact of treatment for mental health problems: a systematic review and narrative synthesis

PURPOSE: This systematic review aimed to synthesise all quantitative literature on the association between social class and the effectiveness of interventions for mental health disorders. METHODS: Systematic literature searches (inception-March 2021) were conducted across 7 databases, and all quantitative studies meeting inclusion criteria, examining the impact of social class on access to treatment, or intervention effectiveness, or the impact of treatment on social mobility, were synthesised narratively. RESULTS: Evidence suggests that lower social class may be associated with reduced access to primary and secondary mental health care and increased likelihood of access via crisis services, and patients of lower social class may not benefit from all mental health interventions, with reduced effectiveness. While limited, there was some indication that psychosocial interventions could encourage increased employment rates. CONCLUSION: Social class is associated with the effectiveness of psychological interventions, and should be considered when designing new interventions to prevent barriers to access and improve effectiveness. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00127-022-02378-9.