Concordance between self- and clinician ratings of depression during inpatient treatment in adolescents: changes over time and probable response shift.

BACKGROUND

Correlations between self-reported and clinician-rated severity of depression are often only moderate, but studies in adults have shown that they increase over time. This study explored whether a similar effect occurs in adolescents and whether initial agreement vs. disagreement between self- and clinician ratings predicts differential outcomes.

METHOD: The analyzed data stem from a randomized controlled trial (DeLight) that explored the effect of bright light therapy as an add-on to treatment as usual in an inpatient sample of adolescents (n = 224). Depression was assessed at four time points (baseline, 4 weeks, 16 weeks, 28 weeks) using the Beck Depression Inventory (BDI-II) as a self-report measure and the Children's Depression Rating Scale - Revised (CDRS-R) as a blinded clinician rating.

RESULTS

The correlation between self- and clinician ratings was only moderate at baseline (r = .40) but increased considerably to a strong correlation at four weeks (r = .72), which was maintained thereafter. The predictive value of initial rater agreement / disagreement for the outcome was small (BDI-II) or non-significant (CDRS-R). Further analyses revealed that the reliability of both instruments increased over time and the factor structure became simpler, with fewer factors and higher factor loadings.

CONCLUSIONS

These findings indicate increasing homogeneity within self- and clinician ratings over time and suggest that some type of response shift occurred, with adolescents appearing to increasingly view their depression as a unified concept. A consideration of response shifts could lead to more accurate assessments of treatment effectiveness.