Development and validation of an infectious disease control competency scale for public health professionals

Abstract Background Infectious diseases persistently pose global threats, and it is imperative to accelerate the professionalization of public health workforce. This study aimed to develop and validate the infectious disease control competency scale (IDCCS) for public health professionals to fill a theoretical gap and elevate practical capabilities by informing public health professionals’ development goals. Methods The initial item pool was generated through a literature review, and categorized into three dimensions (knowledge, practical skills, and leadership) based on the competency iceberg model and public health leadership framework. A two-round Delphi process was conducted to determine indicators within the scale. A pilot survey was utilized for item analysis and exploratory factor analysis (EFA). A formal survey was employed for confirmatory factor analysis (CFA). The weight value of each indicator was calculated using the analytic hierarchy process. Results An initial scale with three primary items, 14 secondary items, and 81 tertiary items was generated. Twenty experts participated in the two rounds of the Delphi process. Authority coefficients exceeded 0.9 in both rounds. Kendall's W was 0.29 and 0.19, respectively (both P < 0.001). Item analysis presented a Cronbach's Alpha of 0.98, with corrected item-total correlation coefficients ranging from 0.33 to 0.78. EFA demonstrated that cumulative variance explanations for the four primary dimensions (knowledge, practical skills, leadership, and personal quality) were 77.463%, 73.976%, 81.174%, and 68.654%, respectively. CFA indicated that all composite reliability values and average variance extracted surpassed 0.8 and 0.5, respectively. The standardized factor loadings of the items ranged from 0.630 to 0.977. Among the seven model fit indices, each of the four dimensions satisfied at least five criteria. A final three-level scale comprising four primary items, 14 secondary items, and 64 tertiary items was constructed. The weight values for the four primary items were 0.4064, 0.2878, 0.2082, and 0.0981, respectively. Conclusions The IDCCS was established to evaluate the competencies of knowledge, practical skills, leadership, and personal quality for public health professionals in infectious disease control. This scale demonstrates good reliability and validity, and can be used for performance evaluation, recruitment processes, curriculum development, and individual self-assessment.