[Patient Factors in Offender Treatment: Personality, Therapy Motivation and Outcome]

Using a systematic literature review according to the PRISMA criteria, patient factors of offenders were related to forensic outcomes. Searches were conducted in the PsycInfo and PSYNDEX databases; further relevant studies were taken from the bibliographies of studies that met the selection criteria. Only quantitative empirical studies for the period 1990-2021 were included. Findings from 31 studies on patient factors (personality, therapy motivation, therapy expectation, satisfaction with therapy) are reported. Patient factors could not always be consistently associated with outcomes. The clearest correlations were found between the expression of anti- or dissocial personality traits and/or psychopathy and (negative) therapy outcomes. Traits usually associated with antisocial developments (impulsivity, anger, rage, hostility) in some cases also correlated negatively with therapeutically desirable outcomes. Patient motivation for therapy should generally have a positive impact on the likelihood of successful forensic therapies, but not all relevant studies pointed in this direction. No studies were identified on the relationships between therapy expectancy or satisfaction and outcome. Based on general psychotherapy research, we suggest that offender therapy could benefit from broader approaches to studying therapy effectiveness.