Positive Predictive Value of ICD-10 Codes to Identify Acute Suicidal and Self Harm Behaviors

The accuracy of diagnosis codes to identify suicidal behaviors, including suicide ideation (SI) and self-harm (SH) events, is unknown. The objective of this study was to determine the positive predictive value (PPV) of International Classification of Disease, 10th Revision codes to identify SI/SH events that may be used in studies using administrative and claims data.

We performed a secondary analysis of a cross-sectional study of children 5 to 17 years of age hospitalized at 2 US children's hospitals with a discharge diagnosis of a neuropsychiatric event, including an SI or SH event. A true International Classification of Disease, 10th Revision SI or SH diagnosis was defined as SI or SH present on admission and directly related to hospitalization as compared with physician record review. PPV with 95% confidence intervals (CIs) were calculated overall and stratified by diagnosis order and age (5 to 11 years vs 12 to 17 years).

There were 376 children or adolescents with a discharge diagnosis of an SI or SH event. The median age was 14 years, and the majority of individuals were female (58%), non-Hispanic White (69%), and privately insured (57%). A total of 332 confirmed SI/SH cases were identified with a PPV of 0.88 (95% CI 0.85-0.91). PPVs were similar when stratified by diagnosis order: primary 0.94 (95% 0.88-0.97) versus secondary 0.86 (95% CI 81-90). PPVs were also similar in adolescents (0.89, CI 0.85-0.92) compared with children (0.84, 95% CI 0.74-0.91).

The use of these validated code sets to identify SI or SH events may minimize misclassification in future studies of suicidal and self-harm hospitalizations.