Cross-specialty PROMIS-global health differential item functioning

Area of Science:

• Health Outcomes Measurement
• Psychometrics
• Patient-Reported Outcomes

Background:

• The PROMIS-Global Health (PROMIS-GH) is a key tool for assessing patient well-being.
• Evaluating its performance across different patient demographics and clinical contexts is crucial for reliable application.
• Previous research has not extensively demonstrated the absence of differential item functioning (DIF) for PROMIS-GH in varied populations.

Purpose of the Study:

• To assess the functioning of PROMIS-Global Health (PROMIS-GH) domains (Global Physical Health and Global Mental Health) across clinical settings, patient age, and medical complexity.
• To evaluate differential item functioning (DIF) within the PROMIS-GH to ensure consistent measurement across diverse patient groups.
• To test the hypothesis that PROMIS-GH domains perform similarly across these varied populations.

Main Methods:

• Retrospective analysis of 7,974 PROMIS Global Health measures using the 'Lordif' package in R.
• Investigation of DIF for Global Mental Health (GMH) and Global Physical Health (GPH) across clinical environments (Orthopedic Surgery, Family Medicine, Internal Medicine).
• DIF analysis was conducted across age groups (≤53, >53-66, >66) and Charlson Comorbidity Index (CCI: 0, 1, 2+) using quasi Monte Carlo estimation, with Wald tests and Benjamini & Hochberg procedure for significance.

Main Results:

• No items within the Global Mental Health (GMH) or Global Physical Health (GPH) domains exhibited differential item functioning (DIF).
• This lack of DIF was consistent across all examined age groups, levels of medical complexity (CCI), and clinical settings.
• The PROMIS-GH demonstrated robust performance without item bias in the evaluated populations.

Conclusions:

• The Global Mental Health (GMH) and Global Physical Health (GPH) items within the PROMIS-GH function comparably across diverse treatment settings, age categories, and medical comorbidities.
• The PROMIS-Global Health (PROMIS-GH) shows significant potential for facilitating interdisciplinary patient care.
• Its consistent performance supports its utility in patient optimization prior to surgical intervention.