Use of PHQ-4 Tool to Assess Anxiety and Depression in Adolescents and Adults in Medically Underserved Santo Domingo, Ecuador

Background : Anxiety and depression are prevalent mental health conditions, yet they often remain underdiagnosed, especially in underserved populations. In Ecuador, mental health disorders are a significant public health concern, with limited access to mental health resources. The Patient Health Questionnaire-4 (PHQ-4) is a widely used, ultra-brief self-reported screening tool for identifying symptoms of anxiety and depression. This study aimed to assess the utility of the PHQ-4 in screening pediatric and adult populations in Santo Domingo, Ecuador, during a medical brigade in August 2020. Methods : The PHQ-4, consisting of two items for depression (PHQ-2) and two items for anxiety (GAD-2), was administered to patients aged 12 and older attending the medical brigade. A total of 380 individuals participated. Screening results were analyzed by age group, sex, and symptom severity, with scores categorized as mild (0-5), moderate (6-8), or severe (9-12). Statistical analysis was performed using IBM SPSS Statistics, including one-way ANOVA, Pearson’s correlation, independent samples t-tests, Pearson’s chi-square, and Fisher’s exact tests Results : The study revealed significant gender differences in anxiety scores, with pediatric females showing a statistically significant higher prevalence of anxiety compared to males (35.8% vs. 12.5%, p < 0.05). While depression scores were higher in females, the difference did not reach statistical significance (33.7% in females vs. 25% in males). Anxiety rates increased with age, while depression rates varied without a significant trend. Notably, the prevalence of anxiety and depression among pediatric patients in this population was higher than the national estimates for Ecuador. Conclusion : The PHQ-4 proved to be an effective screening tool for identifying anxiety and depression in the Santo Domingo population. Significant gender differences in anxiety and depression were observed, with higher rates in females and a noticeable increase in anxiety with age. Given the higher prevalence of mental health disorders in this population, regular use of the PHQ-4 in global medical brigades is recommended to improve the understanding and management of mental health in underserved regions.