Diagnosing depression in primary care settings is challenging. Patients are more likely to present with somatic symptoms, and typically with mild depression. Use of assessment scales is variable. In this context, it is uncertain how general practitioners (GPs) determine the severity of depressive illness in clinical practice. The aim of the current paper was to identify which symptoms are used by GPs when diagnosing depression and when determining severity.

A total of 1760 GPs participated in the RADAR Program, an educational program focusing on the diagnosis and management of clinical depression. GPs identified a maximum of four patients whom they diagnosed with depression and answered questions regarding their diagnostic decision-making process for each patient.

Overall, assessment of depression severity was influenced more by somatic symptoms collectively than emotional symptoms. Suicidal thoughts, risk of self-harm, lack of enjoyment and difficulty with activities were amongst the strongest predictors of a diagnosis of severe depression.

The conclusions are threefold: (1) collectively, somatic symptoms are the most important predictors of determining depression severity in primary care; (2) GPs may equate risk of self-harm with suicidal intent; (3) educational initiatives need to focus on key depressive subtypes derived from emotional, somatic and associated symptoms.