Objective/Purpose: Depression in older adults with cancer (OACs) is poorly captured by standard patient-reported outcomes (PROs), as traditional DSM criteria may overlook unique symptoms in this population. Using the US Food and Drug Administration Guidance for Industry on PRO development, we reconceptualized depression in OACs and created the Older Adults with Cancer-Depression Scale (OAC-D). This study evaluates the psychometric properties of this novel measure.
Sample/Procedures: Based on a refined conceptual model informed by literature reviews, and qualitative work with patients and experts in geriatric oncology and psychiatry, a 35-item draft PRO was developed. The draft, alongside legacy measures, was administered to OACs > 70 years of age at a comprehensive cancer center and across the US. Exploratory Graph Analysis (EGA) identified relevant items and novel factors. Classical Test Theory was applied to assess internal consistency, validity, and test-retest reliability (7–14 days post-baseline).
Results: The mean age of the 155 participants was 76+4.7, and 48% were female, 93% white, 91% non-Hispanic, and 67% college educated. EGA analysis yielded an 18-item measure with five domains: (1) Interest and Enjoyment, (2) Purpose and Meaning, (3) Loneliness, (4) Social Withdrawal, and (5) Guilt and Regrets. Internal consistency (Cronbach’s alpha = 0.85–0.93) and test-retest reliability (ICC = 0.74–0.80, Social Withdrawal = 0.61) were strong. Convergent validity was supported by correlations with the PHQ-9 (r = 0.81), PROMIS-Anxiety (r = 0.68), and PROMIS-Physical (r = -0.41). Known groups analysis showed higher scores for those with a history of depression (p < 0.001).
Conclusions and Clinical Implications: The OAC-D identifies five unique domains of depression, with only one overlapping with DSM criteria. It demonstrates robust psychometric properties and provides a nuanced alternative to DSM-based measures, addressing the distinctive psychological challenges of cancer and aging.