Validation and Psychometric Properties of Suicide Behaviors Questionnaire-Revised (SBQ-R) in Iran

Background: Suicide is increasing in young Iranian population, which necessitates the employing of valid, yet abridged instruments assessing the constellation of suicide-related behaviors. The study aimed at validating Suicide Behavior Questionnaire-Revised (SBQ-R) among Iranian undergraduates.

Methods: A total of 487 undergraduates were surveyed in 2018. Construct validity of SBQ-R was examined via confirmatory factor analysis (CFA), and Spearman's correlation with two single-item indices of suicide acceptability (SA) and lifetime suicidal ideation (LSI) was determined. Logistic regression and Kruskal-Wallis tests were used to examine the cut-off points (≥ 7 and ≥ 8) and categorizations as per item 1.

Results: The mean SBQ-R score was 5.79 ± 3.55. Cut-off points ≥ 7 and ≥ 8 categorized 150 (30.8%) and 123 (25.2%) samples with suicide risk, respectively. Women obtained significantly higher scores on all indices, except items 1 and 4. CFA confirmed the model with sound goodness-of-fit, with factor loadings of 0.70 to 0.83. Composite reliability and average variance extracted were 0.87 and 0.63, respectively. The SBQ-R's correlation with SA and LSI confirmed its concurrent validity. Regression analysis confirmed the ability of both cut-off points to distinguish the participants with high SA and LSI; however, the cut-off point ≥ 8 produced better results regarding high LSI. Based on item 1, normal versus low- and high-risk samples were significantly different in terms of SA, LSI, and adjusted total score of SBQ-R (P < 0.0001).

Conclusion: SBQ-R is an economic and psychometrically sound tool, which can be utilized to identify suicide-related behaviors and risks in young Iranian population.