Development and psychometric validation of a patient-centered Knowledge, Attitude, and Practice (KAP) Questionnaire for Geriatric Cancer Pain Management.

BACKGROUND: This study aimed to develop and psychometrically validate a patient-centered Knowledge-Attitude-Practice (KAP) questionnaire for cancer pain management in Chinese geriatric cancer patients. Existing pain assessment tools were largely developed for younger or mixed-age populations and seldom capture culture-specific psychosocial factors or the patient's own perspective. METHODS: The Knowledge-Attitude-Practice Questionnaire for Geriatric Cancer Pain Management (KAP-CPGQ) was developed across five sequential phases: item generation (literature review and semi-structured key-informant interviews with 6 clinical experts), content validity (a two-round modified Delphi consultation with an independent panel of 12 experts), face validity (cognitive interviewing with 10 geriatric cancer patients), construct validity, and reliability analysis. Construct validity was examined in 440 geriatric cancer patients, randomly partitioned into two independent subsamples (n = 220 each) for exploratory (EFA) and confirmatory factor analysis (CFA). Test-retest reliability was assessed in 30 participants after a 2-week interval. RESULTS: The final instrument retained 28 items across three domains: knowledge (10 items), attitudes (9 items), and practices (9 items), each rated on a 5-point Likert scale. Content validity was supported by an overall content validity ratio (CVR) of 0.90 and a scale-level content validity index (S-CVI/Ave) of 0.91, and all 28 items exceeded the Item Impact Score threshold of 1.5 (range 3.5-4.2). EFA identified a three-factor structure (KMO = 0.94; Bartlett's test p < 0.001) explaining 61.0% of the total variance, with all item loadings >0.50. CFA confirmed good model fit (χ2/df = 1.158; CFI = 0.986; NNFI = 0.984; IFI = 0.986; NFI = 0.903; AGFI = 0.869; RMR = 0.026; RMSEA = 0.027), with standardized factor loadings ranging from 0.66 to 0.83. Reliability was high: overall Cronbach's α = 0.94 (subscales 0.92-0.93), split-half reliability = 0.90 (subscales 0.87-0.89), and 2-week test-retest reliability ranged from 0.89 to 0.91 across the three domains. CONCLUSION: The KAP-CPGQ is a reliable, valid, and culturally adapted instrument measuring knowledge, attitudes, and practices in geriatric cancer pain management. It offers clinicians and researchers a tool to identify patient-level barriers to pain control and to guide targeted educational and behavioral interventions for geriatric cancer patients.