Diagnosis and management of depression in 3 countries: results from a clinical vignette factorial experiment.

OBJECTIVE International differences in disease prevalence rates are often reported and thought to reflect different lifestyles, genetics, or cultural differences in care-seeking behavior. However, they may also be produced by differences among health care systems. We sought to investigate variation in the diagnosis and management of a "patient" with exactly the same symptoms indicative of depression in 3 different health care systems (Germany, the United Kingdom, and the United States). METHOD A factorial experiment was conducted between 2001 and 2006 in which 384 randomly selected primary care physicians viewed a video vignette of a patient presenting with symptoms suggestive of depression. Under the supervision of experienced clinicians, professional actors were trained to realistically portray patients who presented with 7 symptoms of depression: sleep disturbance, decreased interest, guilt, diminished energy, impaired concentration, poor appetite, and psychomotor agitation or retardation. RESULTS Most physicians listed depression as one of their diagnoses (89.6%), but German physicians were more likely to diagnose depression in women, while British and American physicians were more likely to diagnose depression in men (P = .0251). American physicians were almost twice as likely to prescribe an antidepressant as British physicians (P = .0241). German physicians were significantly more likely to refer the patient to a mental health professional than British or American physicians (P < .0001). German physicians wanted to see the patient in follow-up sooner than British or American physicians (P < .0001). CONCLUSIONS Primary care physicians in different countries diagnose the exact same symptoms of depression differently depending on the patient's gender. There are also significant differences between countries in the management of a patient with symptoms suggestive of depression. International differences in prevalence rates for depression, and perhaps other diseases, may in part result from differences among health care systems in different countries.