Introduction: Multisource feedback (MSF) ratings provided by patients and colleagues are often poorly correlated with doctors' self-assessments. Doctors' reactions to feedback depend on its agreement with their own perceptions, but factors influencing self-other agreement in doctors' MSF ratings have received little attention. We aimed to identify the characteristics of doctors and their rater groups that affect self-other agreement in MSF ratings. Methods: We invited 2454 doctors to obtain patient and colleague feedback using the UK General Medical Council's MSF questionnaires and to self-assess on core items from both patient (PQ) and colleague (CQ) questionnaires. Correlations and differences between doctor, patient and colleague mean feedback scores were examined. Regression analyses identified the characteristics of doctors and their rater groups that influenced self-other score agreement. Results: 1065 (43%) doctors returned at least one questionnaire, of whom 773 (73%) provided self and patient PQ scores and 1026 (96%) provided self and colleague CQ scores. Most doctors rated themselves less favourably than they were rated by either their patients or their colleagues. This tendency to underrate performance in comparison to external feedback was influenced by the doctor's place of training, clinical specialty, ethnicity and the profile of his/her patient and colleague rater samples but, in contrast to studies undertaken in nonmedical settings, was unaffected by age or gender. Discussion: Self-other agreement in MSF ratings is influenced by characteristics of both raters and ratees. Managers, appraisers, and others responsible for interpreting and reviewing feedback results with the doctor need to be aware of these influences. (Contains 2 tables and 2 figures.)