Objective: Interpersonal theories of suicide suggest that the Interpersonal Needs Questionnaire (INQ) can be used to measure suicidal ideation, but few studies have focused on migrant people, a group with a high prevalence of suicidal ideation. The aim of this study was to validate the psychometric properties of the INQ-15 and its prediction of suicidal ideation among migrant industrial workers in China.
Method: A stratified multi-stage sample of 2023 industrial workers was recruited from 16 factories in Shenzhen, China. There were 1805 nonlocal workers, which we defined as migrant workers with a mean age of 32.50 ± 8.43 years old who were 67.3% male. The structure of the Chinese version of the INQ-15 and its correlation and predictive utility for suicidal ideation were examined through factor analysis, the Item Response Theory, the M2 test, logistic regression, and receiver operating characteristic (ROC) analysis.
Results: Different from studies among various samples in which a two-factor solution is identified, results within this sample indicated three factors: perceived burdensomeness, thwarted belongingness, and social isolation. The model fit statistics of three-factor INQ were 0.075 for RMSEA, 0.945 for CFI, 0.932 for TLI, and 0.067 for SRMR. The model standard estimated factor loadings ranged from 0.366 to 0.869. The summed scores of INQ and perceived burdensomeness predicted suicidal ideation after controlling for sociodemographic characteristics such as age, gender, and income with AUC of 0.733 (95% CI: 0.712/0.754) and 0.786 (95% CI: 0.766/0.804). In the meantime, the comparison of the predictive ability between INQ total scores and PB scores was significant with p < 0.05.
Conclusion: The INQ has good psychometric properties and can be used to assess how migrant workers living in the Shenzhen perceive meeting interpersonal psychological needs and shows good predictive ability of suicidal ideation. Perceived burdensomeness appears to play a role in suicide and may be a point of intervention, yet the notable deviation from previous findings and the relative weakness of two of the other factors warrant further study.
Keywords: Interpersonal Needs Questionnaire; migrant workers; perceived burdensomeness; social isolation; suicidal ideation; thwarted belongingness.