Abstract
The PHQ-9 is a globally recognized and widely used tool for screening depression. Its importance lies in its ability to assess the DSM criteria for depressive disorders, allowing both diagnosis and assessment of the severity of the condition. However, despite its prevalence internationally, no comprehensive studies on its psychometric properties have been carried out in the Dominican Republic. This lack of reliable and valid psychometric instruments to assess depression entails several significant challenges. On the one hand, it limits diagnostic accuracy, which may result in incorrect or incomplete detection of depressive symptoms. In addition, it hinders proper assessment of the symptomatology and severity of the disorder, which could lead to inappropriate treatments. It also restricts the possibilities for research on depression in the specific context of the Dominican Republic, which hinders a complete understanding of the disease in terms of its cultural and social characteristics. To address this gap in the literature, this study set out to examine the psychometric properties of the PHQ-9 in the Dominican population. For this purpose, we relied on the participation of 1437 Dominicans. The results obtained provide favorable evidence on validity and reliability. In terms of internal structure, a unidimensional model was found to explain a significant proportion of the variability in the responses. In addition, confirmatory analyses showed an excellent fit of the proposed model. In terms of reliability, both McDonald's Omega coefficient and Cronbach's Alpha coefficient yielded values above the accepted threshold of 0.70, indicating adequate internal consistency. Likewise, a strong association was verified between the PHQ-9 and GAD-7 scores, providing additional evidence of criterion validity. These results support previous findings and suggest that the PHQ-9 is a reliable and valid tool to assess depression in the Dominican population.