Background: Suicide is the fifth most important cause of death in China, but the reasons for the high rate and unique pattern of characteristics of those who kill themselves are unknown.
Methods: We pretested, and then administered a comprehensive interview to family members and close associates of 519 people who committed suicide and of 536 people who died from other injuries (controls) randomly selected from 23 geographically representative sites in China.
Findings: After adjustment for sex, age, location of residence, and research site, eight significant predictors of suicide remained in the final unconditional logistic regression model. In order of importance they were: high depression symptom score, previous suicide attempt, acute stress at time of death, low quality of life, high chronic stress, severe interpersonal conflict in the 2 days before death, a blood relative with previous suicidal behaviour, and a friend or associate with previous suicidal behaviour. Suicide risk increased substantially with exposure to multiple risk factors: none of the 265 deceased people who were exposed to one or fewer of the eight risk factors died by suicide, but 30% (90/299) with two or three risk factors, 85% (320/377) with four or five risk factors, and 96% (109/114) with six or more risk factors died by suicide.
Interpretation: Despite substantial differences between characteristics of people who commit suicide in China and the west, risk factors for suicide do not differ greatly. Suicide prevention programmes that concentrate on a single risk factor are unlikely to reduce suicide rates substantially; preventive efforts should focus on individuals exposed to multiple risk factors.