Association between continuity of care and treatment outcomes in psychiatric patients in Germany: a prospective cohort study

BACKGROUND: Continuity of care is considered an important treatment aspect of psychiatric disorders, as it often involves long-lasting or recurrent episodes with psychosocial treatment aspects. We investigated in two psychiatric hospitals in Germany whether the positive effects of relational continuity of care on symptom severity, social functioning, and quality of life, which have been demonstrated in different countries, can also be achieved in German psychiatric care. METHODS: Prospective cohort study with a 20-months observation period comparing 158 patients with higher and 165 Patients with lower degree of continuity of care of two psychiatric hospitals. Patients were surveyed at three points in time (10 and 20 months after baseline) using validated questionnaires (CGI Clinical Global Impression rating scales, GAF Global Assessment of Functioning scale, EQ-VAS Euro Quality of Life) and patient clinical record data. Statistical analyses with analyses of variance with repeated measurements of 162 patients for the association between the patient- (EQ-VAS) or observer-rated (CGI, GAF) outcome measures and continuity of care as between-subject factor controlling for age, sex, migration background, main psychiatric diagnosis group, duration of disease, and hospital as independent variables. RESULTS: Higher continuity of care reduced significantly the symptom severity with a medium effect size (p 0.036, eta 0.064) and increased significantly social functioning with a medium effect size (p 0.023, eta 0.076) and quality of life but not significantly and with only a small effect size (p 0.092, eta 0.022). The analyses of variance suggest a time-independent effect of continuity of care. The duration of psychiatric disease, a migration background, and the hospital affected the outcome measures independent of continuity of care. CONCLUSION: Our results support continuity of care as a favorable clinical aspect in psychiatric patient treatment and encourage mental health care services to consider health service delivery structures that increase continuity of care in the psychiatric patient treatment course. In psychiatric health care services research patients’ motives as well as methodological reasons for non-participation remain considerable potential sources for bias. TRIAL REGISTRATION: This prospective cohort study was not registered as a clinical intervention study because no intervention was part of the study, neither on the patient level nor the system level.