Reliability and validity of the simplified Chinese version of the Functional Assessment of Cancer Therapy-Immune Checkpoint Modulator

Abstract

Purpose: This study aimed to translate and culturally adapt the immune checkpoint modulator (ICM) subscale of the Functional Assessment of Cancer Therapy-Immune Checkpoint Modulator (FACT-ICM) scale and to validate the FACT-ICM scale in Chinese cancer patients receiving immune checkpoint inhibitors (ICIs) treatment.

Methods: In total, 354 cancer patients treated with ICIs were included in our cross-sectional study including 2 phases. Firstly, the ICM subscale was translated and culturally adapted by standardized procedures. Then the FACT-ICM scale was validated, which included item analysis, content validity, floor and ceiling effects, internal consistency reliability, test-retest reliability, construct validity, convergent/divergent validity, and known-group validity.

Results: The content validity indexes at the item and scale level of the ICM subscale were greater than 0.8. No floor and ceiling effects were found. The Cronbach's α and McDonald's omega coefficients of the simplified Chinese version of the FACT-ICM scale were 0.935 and 0.936, and the intraclass correlation coefficient was 0.833 (95% confidence interval: 0.574-0.940). Confirmatory factor analysis confirmed the 5-subscale structure of the simplified Chinese version of the FACT-ICM scale (χ²/df = 2.144, RMSEA = 0.057, SRMR = 0.072, and CFI = 0.848). Convergent and divergent validity further supported the construct validity of the simplified Chinese version of the FACT-ICM scale. The known-group validity of the simplified Chinese version of the FACT-ICM scale was confirmed in patients with different physical statuses.

Conclusions: The simplified Chinese version of the FACT-ICM scale is a valid and reliable instrument and can be used in clinical practice and research on cancer patients receiving ICIs treatment.

Keywords: Functional Assessment of Cancer Therapy-Immune Checkpoint Modulator scale; Immune checkpoint inhibitors; Immunotherapy; Patient-reported outcome measures; Psychometric validation; Quality of Life.