Development of the HeQ

At the beginning of the questionnaire construction a thorough literature review was conducted by the first author, to check if a hesitancy questionnaire had already been published, resulting to papers mainly addressing vaccine hesitancy reporting on tools identifying vaccine hesitant persons (Cella et al., 2020; Shapiro et al., 2018) and one addressing social support seeking (Gontkovsky et al., 2021). Then, a brainstorming session was carried out with the rest of the authors, where the purpose was to discuss the impact of the lockdown measures and recommend as many questions as possible. Finally, in a focused group discussion, an expert panel of five members (two clinical psychologists, one health psychologist and two psychiatrists) evaluated all the questions proposed to be included in the questionnaire, with respect to face validity, content validity, and comprehensiveness. They rated the meaning and linguistic clarity towards instructions, items and response format. A dichotomous response choice (adequate–inadequate) was used by the raters to assess clarity and content. Items that received “inadequate” by three reviewers were excluded (5 items due to lack of linguistic clarity, and 10 items due to content vagueness). Items that received “inadequate” by one or two reviewers were reassessed before final decision of exclusion or inclusion (3 items excluded). Items with similar content were merged (from 16 to 8 items). Items with ambiguous wording were rephrased. Eligible items were selected by full agreement among the panel members. Recommended changes were applied to the final version by the research team. Out of the 40 original questions, 14 were selected and formed the questionnaire to be tested in the pilot study.