Background People increasingly use the Internet to seek health information. However, the overall quality of online health information remains low. This situation is exacerbated by the unprecedented “infodemic”, which has had negative consequences for patients. Therefore, it is important to understand how users make judgements about health information by applying different judgement criteria. Objective The objective of this study is to determine how patients apply different criteria in their judgement of the quality of online health information during the pandemic. In particular, we investigate whether there is consistency between the likelihood of using a particular judgement criterion and its perceived importance among different groups of users. Methods A cross-sectional survey was conducted in one of the leading hospitals in a coastal province of China with a population of forty million. Combined-strategy sampling was used to balance the randomness and the practicality of the recruiting process. A total of 1063 patients were recruited for this study. Chi-square and Kruskal–Wallis analyses were used to analyse the survey data. Results In general, patients make quality judgement of health information more frequently based on whether it is familiar, aesthetic, and with expertise. In comparison, they put more weights on whether health information is secure, trustworthy, and with expertise when determining its quality. Criteria that were considered more important were not always those with a higher likelihood of being used. Patients may not use particular criteria, such as familiarity, identification, and readability, more frequently than others even if they consider them to be more important than other do and vice versa. Surprisingly, patients with a primary school degree put more weight on whether health information is comprehensive than those with higher degrees do in determining its quality. However, they are less likely to use this guideline in practice. Conclusions To the best of our knowledge, this is the first study to investigate the consistency between the likelihood of using certain quality judgement criteria and their perceived importance among patients grouped by different demographic variables and eHealth literacy levels. The findings highlight how to improve online health information services and provide fine-grained customization of information for users.

BACKGROUND People are increasingly using the Internet to seek for health information. However, the overall quality of online health information remains low. The situation is exacerbated by the unprecedented “infodemic”, the flood of rumors and conspiracy theories through various online platforms, which brings about negative consequences to patients. Therefore, it is important to understand how users make these judgments to help them in making better judgments on health information quality, as well as providing customized information services for different groups of users during the pandemic. OBJECTIVE The objective of this study is to find out how patients apply these different criteria in their judgment of online health information quality during the pandemic, in terms of how frequently they apply these criteria and how important they consider them. In particular, we are going to investigate whether there is a consistency between the likelihood to use a particular criterion and its perceived importance in judging the quality of health information among group of users with different demographics (age, gender, educational and income levels) and levels of health literacy. METHODS A cross-sectional survey was conducted in one of the leading hospitals from a coastal province of China with a population of forty million. A combined-strategy sampling (randomization stratification and systematic sampling) was taken to balance the randomness and the practicality of the recruiting process. 1063 patients were recruited in this study. Two kinds of statistical analysis were adopted in this study. For whether a particular criterion was used by the patient, Chi-square analysis was used to compare the group differences in the frequency of criterion use since it was a binary variable. For the perceived importance of each criterion, non-parametric analysis (Kruskal-Wallis) was used to compare the group differences (the normal distribution assumption was not guaranteed). RESULTS It was found that the pattern of the inclination to use certain criteria to judge the quality of online information was not always consistent with the pattern of their perceived importance among patient groups with different ages, genders, educational levels, and eHealth literacy levels. For particular criteria such as familiarity, identification, and readability, patients in one demographic group may not use them more frequently than other groups even they consider these criteria as more important than the other groups do. Moreover, patients in particular groups may use these criteria more frequently even they do not consider them as more important than other groups do. Furthermore, it is surprised to find that patients merely with the primary school degree considered the comprehensiveness criterion as more important than those with the bachelor's degree but less likely to use it in practice, which is counter-intuitive to our commonsense. In the coming sections, the results are interpreted and discussed with both theoretical and practical implications. CONCLUSIONS To the best of our knowledge, it is the first study to investigate the consistency between the pattern of the likelihood to use certain quality judgment criteria and the pattern of their perceived importance among patients grouped by different demographic variables and eHealth literacy levels. The findings share lights on how to improve the online health information services and provide fine-grained customization of information for users, which make the judgment easier and faster.