Development of a vaccine hesitancy scale for childhood immunization in China

Vaccine hesitancy is a primary factor that influences vaccine uptake; however, no specific measurement tool to accurately assess vaccine hesitancy is available in China. This study aimed to develop a general vaccine hesitancy scale for childhood immunization.

We adopted a three-phase process with nine steps to develop and finalize our scale. The scale framework and initial item pool were determined by a literature review. Expert consultation and cognitive interviews with parents were conducted to evaluate content validity. Questionnaire surveys involving parents of children aged <6 years were conducted to select items. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were employed to identify and validate the scale factor structure. The scale's reliability and validity were assessed using multiple indicators.

Of the initial 38 items, 21 were retained after expert consultation and cognitive interviews. In survey 1, the number of scale items decreased to 16 following item analysis and EFA. In survey 2, four items were added and EFA identified four factors. In survey 3, CFA confirmed the four-factor structure and the reliability indicators were satisfactory for the total scale. The level of vaccine hesitancy assessed by our scale was positively associated with vaccination refusal behavior and the Vaccine Hesitancy Scale score. The final scale comprised four dimensions (confidence, complacency, convenience, and calculation) with 17 items.

We developed a validated and reliable measurement to assess vaccine hesitancy among parents of children, which promises to be suitable for wide use in China.