Validation of the Poisoning Severity Score (PSS) in suicidal behavior by self-poisoning.

Intentional self-poisoning is the leading method of suicidal behavior leading to medical attention worldwide. The medical severity of self-poisoning events has major treatment, prognostic, and medico-legal implications, yet measures of severity are limited. The Poisoning Severity Score (PSS) is a widely used scale but validation data are limited, particularly in the study of suicidal behavior per se. The sample was a consecutive series of intentional self-poisoning patients aged 13 to 65 treated at a large university medical center (n = 673). PSS scores, with a range 0 (none) to 4 (death), were calculated along with other structured clinical data and analyzed in a series of linear regressions adjusted for age and sex. Higher PSS scores were consistently associated with greater medical morbidity and more intensive acute medical treatments, and nearly all effect sizes were large. Results support the validity of the PSS in hospital-treated self-poisoning patients.