Toward Understanding of Suicidality in a Spanish Clinical Population: Validation of the European Spanish Version of the Interpersonal Needs Questionnaire

Abstract

Introduction: Suicidal ideation (SI) represents one of the most prominent predictors of suicidal behavior (SB). The Interpersonal Needs Questionnaire (INQ) was developed from the Interpersonal Theory of Suicide (ITS) to assess the 2 core drivers of SI proposed by the theory. Despite the relevance of suicide-related ideations and ITS, there is a lack of psychometric measures validated in clinical Spanish population that adequately evaluate SI components of ITS. Thus, the main aim of the study was to validate INQ-10 in a Spanish clinical sample including the genuine cultural and linguistic characteristics of European Spanish. Methods: 315 participants were included in the analyses; 149 of them consulted mental health services for the presence of suicide-related behaviors. A series of exploratory and confirmatory factor analyses were carried out to identify the factor solution. Bivariate and multivariate analyses were used to analyze psychometric properties. Finally, sensitivity and specificity properties were explored through receiver-operating characteristic analyses which also provided the cut-off values of the questionnaire. Results: An 8-item version demonstrated a good fit to the 2-factor solution. Likewise, this 8-item version showed good psychometric properties. Sensitivity and specificity indices of the version validated as well as the calculated cut-off points were excellent. Conclusions: The current results demonstrate the utility of an 8-item INQ European Spanish version as a valid measure of the current SI in Spanish clinical population. In addition, the validated form reflects the theoretical framework on which it was built.