Spanish validation of the PHQ-A depression severity questionnaire: Invariance between cisheterosexual and LGBTQ+ adolescents

Introduction Limited evidence exists regarding whether the Patient Health Questionnaire-9 for Adolescents (PHQ-A) functions equivalently across cisheterosexual and LGBTQ+ adolescents.Method A total of 1,004 Spanish adolescents aged 14–17 years completed a gender-neutral Spanish PHQ-A adaptation, the Paykel Suicide Scale and two single-items about happiness and life satisfaction.Results The PHQ-A showed excellent one-factor fit, strong internal consistency, convergent validity, and invariance between cisheterosexual and LGBTQ+ adolescents. Higher depression scores were observed among gender and sexual minority youth.Conclusion The Spanish PHQ-A is a reliable instrument for assessing depressive symptoms and supports meaningful comparisons between cisheterosexual and LGBTQ+ adolescents.