AbstractObjectiveTherapist characteristics are known to affect treatment outcome in general and could also influence the use of systematic client feedback (SCF). The current study explores the effect of feedback orientation, regulatory focus, self‐efficacy, attitude towards feedback resources and perceived feedback validity on the use and outcome of SCF in outpatient mental healthcare.MethodThe data of therapists (n = 12) and patients (n = 504) of two outpatient centres offering brief psychological treatment were analysed when SCF, based on the Partners for Change Outcome Management System (PCOMS), was added to treatment as usual. The data of therapists were obtained through a therapist questionnaire composed of relevant characteristics from feedback studies in social and organizational psychology. The effect on the use of SCF was analysed using logistic regression; whereas, the effect on outcome was assessed using a two‐level multilevel analysis. Regular use of SCF and the Outcome Questionnaire (OQ‐45) were used as outcome variables. DSM‐classification, sex and age of each patient were included as covariates.ResultsHigh perceived feedback validity significantly increased the use of SCF. No significant therapist characteristics effects were found on outcome, but high promotion focus was associated with treating more complex patients.ConclusionsThe perceived feedback validity of SCF is likely to have an influence on its use and is probably affected by the changes in the organizational climate.