From PHQ-2 to SRS-22: how a depression screening tool relates to SRS scores in patients with adolescent idiopathic scoliosis

Purpose The aim of our study was to determine the relationship between Patient Health Questionnaire (PHQ) scores—a simple, validated depression screening tool—and Scoliosis Research Society (SRS)-22 questionnaire scores in patients with idiopathic scoliosis (IS). Methods IS patients screened for depression with the PHQ-2 who completed the SRS-22 over a 2-year period were reviewed. If PHQ-2 scores were positive (> 3), the more comprehensive PHQ-9 was administered. Median SRS-22 scores between positive and negative PHQ screens were compared. Nonparametric correlation between PHQ and SRS-22 Mental Health (MH) domain was performed. The ability of the MH domain to discriminate between patients with positive versus negative screens and patients with moderate–severe depression risk versus no–mild risk was evaluated with ROC analysis. Results 521 patients were included. Patients with + PHQ-2 screens had significantly lower total and individual domain SRS scores, especially within the MH domain (4.0 vs. 3.2). For those with moderate-severe depression risk, total and individual domain scores were also significantly lower (MH domain, 4.0 vs. 3.0, p < 0.05). A weak, but significant correlation was observed between the PHQ and MH domain scores (rho = 0.32, p < 0.001). A cut-off of ≥ 3.6 on the MH domain demonstrated sensitivity of 0.75 and specificity of 0.86 for identifying patients at no–mild risk for depression. Conclusion Recognizing mental health conditions is critical to successful IS treatment as psychosocial conditions can negatively affect treatment outcomes. IS patients scoring < 3.6 on the SRS-22 MH domain should be considered for depression screening due to an increased risk of moderate–severe depression.