Prediction of suicide is beyond our present competence, but groups of persons with an increased risk of suicide may be identified. Because suicide is an infrequent event, a heavy preponderance of false-positives (persons not truly suicidal), who share the characteristics of high-risk persons, may overwhelm the detection system. Clinical diagnoses of affective disorder (depressive illness) and alcoholism, found in the majority of suicides, carry implications of greatly increased risk of suicide, especially under certain circumstances.
It is argued that the problem of false-positives, which is relevant to demographic predictors, is irrelevant in these cases because such persons should receive psychiatric treatment in any event. If successful, such treatment should prevent some suicides.