Assessing quality in inpatient psychiatry using outcome scales from the interRAI-Mental Health

Objective: This is the second study in a series to validate an outcome measure for inpatient psychiatry using outcome scales from the interRAI Mental Health (MH). To further validate the Composite Index of Inpatient Mental Health Status (CIIMHS) and its cross-cutting symptom domains by evaluating the relationship between the CIIMHS, its Domain Scores, and the Global Assessment of Functioning (GAF) (convergent validity). To evaluate the responsiveness of the interRAI MH scale scores and the CIIMHS and its Domain Scores to treatment effects. To use the CIIMHS to calculate an effect size (ES) for entry into a hospital’s Balanced Scorecard (BSC).
Methods: We collected pre- and post-treatment scores on eight outcome scales from all RAI-MH assessments of hospital inpatients conducted over two fiscal years, along with GAF scores for one fiscal year, at a large mental health specialty hospital. Building on our previous work, which included a Principal Components Analysis (PCA) of the eight scales, yielding four standardized domain scores (psychosis, depression, impairment, and aggression), we combined these into the CIIMHS. To assess convergent validity, we calculated both parametric and nonparametric correlations between these measures and the GAF scores recorded during the same assessments. To evaluate construct validity, we analyzed changes in scale and domain scores from pre- to post-inpatient treatment across the hospital as a whole and separately for its acute care and addiction inpatient programs.
Results: Among all hospital patients and within the acute care program, pre- and post-treatment differences were statistically significant for seven of the eight RAI-MH scale scores, the composite measure, and the four domain scores (construct validity). Correlations between the GAF and the composite measure, as well as GAF and the impairment domain, approached or exceeded 0.60 (convergent validity). Correlations between GAF and other domains were smaller but were statistically significant, especially after treatment. The addiction program showed pre- and post-treatment differences in the scales with pre-treatment elevations, the composite measure, and the depression domain. Pre- and post-treatment outcome scales in the RAI-MH assessment platform demonstrated treatment effects, confirming good construct validity. Relationships with GAF indicated strong convergent validity. We suggest a methodology based on the CIIMHS to calculate a treatment ES for inclusion in the hospital’s BSC.The CIIMHS is a common measure of illness severity.
Conclusions: T1vT2 differences, calculated quarterly, can be entered into hospital BSCs indicating quality of care.