# Psychometric properties of the Spanish version of the Patient Health Questionnaire in Mexican adolescents

## TL;DR

This study evaluated the reliability and validity of the Spanish version of the PHQ-9 depression screening tool in Mexican adolescents.

## Contribution

The study confirms the PHQ-9's psychometric suitability for Mexican adolescents, including measurement invariance by sex.

## Key findings

- Both one-factor and two-factor models of the PHQ-9 showed very good fit in the sample.
- Internal consistency coefficients ranged from 0.779 to 0.896, indicating acceptable reliability.
- The PHQ-9 demonstrated strong measurement invariance by sex and high correlation with the GAD-7.

## Abstract

The present study aimed to contribute to the analysis of the psychometric properties of the Patient Health Questionnaire (PHQ-9) in a sample of adolescents residing in San Luis Potosí (SLP), Mexico.

768 adolescents from SLP, Mexico, participated in the study. Confirmatory factor analysis (CFA) was conducted to test the one and two-factor models, taking into account the ordinal nature of the items in the model estimation method. Internal consistency was evaluated using the Coefficient alpha (α) and Coefficient omega (ω). Invariance measurement by sex was tested. Also, the relationship with the General Anxiety Disorder (GAD-7 scale) was tested.

The CFA analyses indicated that both models, the one-factor model and the two-factor model, had a very good fit. The single factor and the two factors of the models demonstrated acceptable internal consistency (Coefficient alpha ranging from 0.779 to 0.896). Both models demonstrated measurement invariance by sex up to the Strong level. Additionally, a high Pearson correlation was found between the PHQ-9 and GAD-7 total scores (r = 0.812).

It is concluded that the PHQ-9 scale presents good psychometric properties for the Mexican adolescent population.