Translation, Cultural Adaptation, and Nationwide Validation of the Chinese Version of the Clear Communication Index (Preprint)

BACKGROUND Clear and comprehensible health information is essential for the public to accurately understand and appropriately apply. The Clear Communication Index (CCI), developed by the U.S. Centers for Disease Control and Prevention (CDC), is a standardized tool for assessing the clarity and actionability of health materials, but no standardized version adapted to the Chinese context has been established. OBJECTIVE This study aims to translate and culturally adapt the CCI into Chinese, validate its psychometric properties, and assess the quality of diabetes health communication materials published by provincial CDCs across mainland China. METHODS Following a standardized cross-cultural process (forward–back translation and expert review), we developed the Chinese version of the CCI (C-CCI) and finalized a 12-item scale across four dimensions (Main Message and Call to Action, Behavioral Recommendations, Numbers, Risk) with yes/no scoring (0-100) . One top-ranked diabetes health education material was sampled from each provincial CDC website in mainland China (30/31 included; 96.8%) on May 18, 2025. Twelve trained raters independently evaluated each article (360 ratings). Structural validity was examined using Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). Content validity was assessed by the Item-level Content Validity Index (I-CVI) and the Scale-level Content Validity Index/Average (S-CVI/Ave). Internal consistency (Cronbach's α), inter-rater agreement (Fleiss ' s Kappa), and convergent/discriminant validity were assessed using Composite Reliability (CR) and Average Variance Extracted (AVE). RESULTS The four-factor structure was supported. Content validity was high, with S-CVI/Ave values of 0.976 for clarity and 1.000 for relevance. Internal consistency was acceptable overall (Cronbach's α= 0.837; subscales = 0.827 - 0.910), with substantial inter-rater agreement (Fleiss's Kappa = 0.624). Convergent validity (CR = 0.897 - 0.914; AVE = 0.645 - 0.831) and discriminant validity were satisfactory. Across 30 provincial CDC websites, the mean C-CCI score was 53.84 ± 29.74, well below the recommended threshold of 90. There were no statistically significant regional differences in overall scores; however, Behavioral Recommendations were higher in western than in eastern (P=.001) and central regions (P=.008). CONCLUSIONS The C-CCI showed evidence of validity and reliability in the Chinese context and was feasible for evaluating health communication materials. Nationwide application to diabetes materials indicates suboptimal overall quality, highlighting the need for clearer main messages and calls to action, improved presentation of numbers and risks, and more actionable behavioral guidance. CLINICALTRIAL This study was approved by the ethics review board of Hangzhou Normal University, China. The review number is 2025063.