Table 7

Prospective analysis of patient data (1997–2008) with symptom episodes followed by a depressive episode within 3 months: positive and negative predictive values of unexplained and somatic symptoms for depressive disorder

			Positive	Negative
Symptoms	Pretest, %	Post-test, %	predictive value, %	predictive value, %
Somatoform
Tiredness	0.014	0.014	0.014	0.986

Fainting	0.014	0.014	0.014	0.986

Abdominal pain	0.014	0.010	0.010	0.986

Nausea	0.014	0.021	0.021	0.986

Constipation	0.014	0.014	0.014	0.986

Palpitations	0.014	0.012	0.012	0.986

Low back complaint	0.014	0.007	0.007	0.986

Chest symptoms	0.014	0.005	0.005	0.986

Muscle pain	0.014	0.008	0.008	0.986

Headache	0.014	0.011	0.011	0.986

Dizziness	0.014	0.009	0.009	0.986

Disturbances of sleep	0.014	0.026	0.025	0.986

Shortness of breath	0.014	0.015	0.014	0.986

Somatic

Lymph gland enlargement	0.014	0.005	0.005	0.986

Localised abdominal pain	0.014	0.008	0.008	0.986

Diarrhoea	0.014	0.013	0.013	0.986

Red eye	0.014	0.005	0.005	0.986

Swollen ankles	0.014	0.013	0.012	0.986

Shoulder symptoms	0.014	0.009	0.009	0.986

Hand/finger symptoms	0.014	0.006	0.006	0.986

Hip symptoms	0.014	0.005	0.005	0.986

Tingling fingers/toes/feet	0.014	0.000	0.000	0.986

Cough	0.014	0.008	0.008	0.986

Throat symptoms	0.014	0.007	0.007	0.986

Pruritus	0.014	0.007	0.007	0.986

Urinary frequency	0.014	0.013	0.013	0.986

Positive predictive value: the chance that a patient consulting the GP with a symptom has depression (incidence). Negative predictive value: the chance that a patient who does not present the symptom episode does not have depressive disorder.