A Comparison of Depressive Symptom Self-Reported Measures in the Texas Youth Depression and Suicide Research Network (TX-YDSRN)

Psychometric evaluation and linking of the PHQ-9, QIDS-C, and VQIDS-C in a real-world population with major depressive disorder

Purpose

Major depressive disorder (MDD) is a leading cause of disability worldwide. An accurate assessment of depressive symptomology is crucial for clinical management and research. This study assessed the convergent validity, reliability, and total scale score interconversion across the 9-item Patient Health Questionnaire (PHQ-9) self-report, the 16-item Quick Inventory of Depressive Symptomatology-clinician report (QIDS-C) (two widely used clinical ratings) and the 5-item Very Brief Quick Inventory of Depressive Symptoms-clinician report (VQIDS-C), which evaluate the core features of MDD.

Patients and Methods

This study leveraged electronic health record (EHR)-derived, de-identified data from the NeuroBlu Database (Version 23R1), a longitudinal behavioural health real-world platform. Classical Test Theory (CTT) and Item Response Theory (IRT) analyses were used to evaluate the reliability, validity of, and conversions between the scales. The Test Information Function (TIF) was calculated for each scale, with greater test information reflecting higher precision and reliability in measuring depressive symptomology. IRT was also used to generate conversion tables so that total scores on each scale could be compared to the other.

Results

The study sample (n = 2,156) had an average age of 36.4 years (standard deviation [SD] = 13.0) and 59.7% were female. The mean depression scores for the PHQ-9, QIDS-C, and VQIDS-C were 12.9 (SD = 6.6), 12.0 (SD = 4.9), and 6.18 (SD = 3.2), respectively. The Cronbach's alpha coefficients for PHQ-9, QIDS-C, and VQIDS-C were 0.9, 0.8, and 0.7, respectively, suggesting acceptable internal consistency. PHQ-9 (TIF = 30.3) demonstrated the best assessment of depressive symptomology, followed by QIDS-C (TIF = 25.8) and VQIDS-C (TIF = 17.7).

Conclusion

Overall, PHQ-9, QIDS-C, and VQIDS-C appear to be reliable and convertible measures of MDD symptomology within a US-based adult population in a real-world clinical setting.

Measurement-Based Care for Depression in Youth: Practical Considerations for Selecting Measures to Assess Depression, Associated Features and Functioning

Identification and management of major depressive disorder (MDD) in children and adolescents remains a significant area of public health need. The process for identifying depression (e.g. screening) and management (e.g. measurement based care [MBC]) is substantially enhanced by utilization of clinical measures and rating scales. Measures can be self- or caregiver reported or clinician rated. They can aid recognition of at-risk individuals for future assessment and assist in clinical diagnosis and management of depression. In addition to assessing symptoms of depression, rating scales can be used to assess important associated features (e.g. anxiety, trauma) and functional outcomes (e.g. quality of life, performance/productivity). In this manuscript, we discuss practical considerations for clinicians and researchers when selecting rating instruments for assessing depression, associated factors, functioning, and treatment outcomes (i.e. adherence and side effects) as part of MBC in youth and provide a summary of rating scales commonly used in research and clinical settings.