Understanding factors that affect treatment adherence may help to prevent non-adherence and increase the quality of care as well as cost-effectiveness.

To measure the level of adherence to clinical guidelines and to examine the correlates of adherence among outpatients with mood, anxiety and somatoform disorders in a routine clinical setting.

We developed quality measures and assessed adherence during up to 3 years of follow-up in a randomly selected sample of 300 outpatients who started routine psychiatric treatment. Patients were treated with pharmacotherapy, psychotherapy or a combination. At baseline, a standardized diagnostic interview (MINI-PLUS), the brief symptom inventory (BSI), general health status (SF-36) and demographics were assessed, as part of the usual intake procedure. Using multivariable regression analysis we identified independent predictors associated with guideline adherence.

Most indicators were highly positive, indicating that most treatment was delivered according to guidelines. The combined treatment group as compared to the two other groups had lower scores on indicators “correct treatment module” and “stepped care” (p < 0.005). Patients receiving psychotherapy scored best on the separate indicators. Only a minority was treated in complete accordance with guidelines. Low-adherence was independently predicted by a low score on the SF-36 vitality-subscale. No significant differences were found within socio-demographic variables, comorbidity and BSI-scores between the adherence groups.

Assessment of guideline adherence is feasible with this cross-diagnostic set of process indicators. Patients with low scores on the vitality-subscale of the SF-36 were at the highest risk to receive low guideline-concordant care.