Validation of Goal Attainment Scaling for Depression: Initial Findings From an Open-label Study in Patients Switching to Vortioxetine

Goal attainment scaling (GAS) for evaluating individualized patient treatment goals and progress was adapted for MDD (GAS-D) in an open-label study in patients switching to vortioxetine (n=122). Subjects established 3 goals at baseline (1 self-defined and 2 “domain-defined”), with evaluation over 12 weeks. Importance/achievability rankings of goals were collected with other endpoints.
Convergent and divergent validity of GAS-D, correlations with measures of depressive symptoms (PHQ-9), illness severity and improvement (CGI-S, CGI-I), quality of life (QOL)/functioning (Q-LES-Q), cognitive performance (DSST), and cognitive symptoms (PDQ-D) were evaluated. A latent factor analysis/structural equation model (SEM) was developed to evaluate relationships between GAS-D, depressive symptoms, cognitive performance, and functional improvement.
At weeks 6 and 12, all 3 goal scores correlated significantly with measures of depressive symptoms (PHQ-9) and illness severity and improvement (CGI-S, CGI-I) (p<0.05). QOL measures demonstrated strong relationships to GAS-D, particularly Work domain and self-defined goal (r=0.382, p<0.001). Cognitive symptoms evaluated by PDQ-D and PDQ-D5 subset were significant at weeks 6 (r=-0.225, p<0.001 and r=-0.201, p<0.05, respectively) and 12 (r=-0.249, p<0.05 and r=-0.251, p<0.05, respectively). Cognitive performance evaluated by DSST was related to self-defined goals at week 12 (r=0.332, p<0.01) and demonstrated statistically significant correlations with DSST change over time (r=0.201, p<0.05). Using latent factor analysis and SEM, GAS-D, specifically the self-defined goal, was persistently related to functionality, regardless of level of improvement in depressive symptoms.
GAS-D demonstrates many features of a valid, sensitive assessment tool. Using a variable-construct approach, GAS-D scores may be an indicator of functional recovery in depression.