Psychometric evidence of the Patient Health Questionnaire (PHQ-9) and Generalized Anxiety Scale (GAD-7) in patients with genetic counseling in Oncology

Abstract

Introduction: The symptoms of depression and anxiety in patients receiving Genetic Counseling in Oncology (AGO) are among the most prevalent psychological affectations, so their timely, valid, and reliable identification is a priority. Objective: To determine the psychometric properties of the Patient Health Questionnaire, PHQ-9, and the Generalized Anxiety Scale, GAD-7, in cancer patients carrying germinal pathogenic variants in high susceptibility genes. Method: An instrumental, crosssectional design was used with a non-probabilistic sampling. 163 participants with pathogenic variants in BRCA1/BRCA2, associated with hereditary cancer, between 19 and 79 years (48.2 ± 11.2 years) were included. Statistical analysis: The construct validity of each instrument was tested through an exploratory and confirmatory factor analysis. Results: The GAD-7 obtained α = 0.899 and 62.3% of the explained variance, on the other hand, the PHQ-9 obtained α = 0.896 and 54.8% of the explained variance. Confirmatory factor analysis suggests that the theoretical models of both instruments fit a single factor, with adequate consistency and validity indices. Discussion and conclusion: The PHQ-9 and the GAD-7 are parsimonious, brief, valid and reliable instruments for the detection of symptoms of depression and anxiety in patients receiving AGO, in the Mexican population. Its use is recommended in clinical care (at baseline, and during follow-up), as well as in future research.