Background: When people require medical treatment, many risk factors including adverse medical events, economic burdens, and social-psychological consequences may contribute to their hesitation to seek medical help. Therefore, a reliable and valid instrument that can comprehensively assess the risk perception of medical help-seeking behavior among ordinary Chinese adults should be developed. Methods:The basic dimensions of the scale were determined based on literature review and in-depth interviews with patients. Then, an item pool with 32 items and six dimensions was developed. After the item reduction process based on item and factor analyses, a three-factor, 16-item scale was established. From March 2019, this scale was distributed among 639 healthy adults, outpatients, or inpatients in 20 provinces and municipalities in the mainland of China by convenience sampling. Then, the reliability and validity of the scale were examined. Results:The scale consists of three dimensions (treatment risks, burden risks, and stigma risks) and 16 items. The root-mean-square error of approximation, comparative fit index, and Tucker-Lewis index of this model were 0.069, 0.925, and 0.910, respectively. The internal consistency reliability of the scale was 0.893, and the test-retest reliability was 0.784. The criterion-related validity was 0.720 (P<0.01). Conclusions:The risk perception scale of medical help-seeking behavior is a reliable and valid instrument to measure Chinese adults' perception for potential risks in the process of medical treatment.

Background The proliferation of vaccine misinformation on social media has seriously corrupted the public’s confidence in vaccination. Proactively sharing provaccination messages on social media is a cost-effective way to enhance global vaccination rates and resist vaccine misinformation. However, few strategies for encouraging the public to proactively share vaccine-related knowledge on social media have been developed. Objective This research examines the effect of value type (individual vs collective) and message framing (gain vs loss) on influenza vaccination intention (experiment 1) and the willingness to share provaccination messages (experiment 2) among Chinese adults during the COVID-19 pandemic. The primary aim was to evaluate whether messages that emphasized collective value were more effective in increasing the willingness to share than messages that emphasized individual value. Methods We enrolled 450 Chinese adults for experiment 1 (n=250, 55.6%) and experiment 2 (n=200, 44.4%). Participants were randomly assigned to individual-gain, individual-loss, collective-gain, or collective-loss conditions with regard to the message in each experiment using the online survey platform’s randomization function. Experiment 1 also included a control group. The primary outcome was influenza vaccination intention in experiment 1 and the willingness to share provaccination messages in experiment 2. Results The valid sample included 213 adults in experiment 1 (females: n=151, 70.9%; mean age 29 [SD 9] years; at least some college education: n=202, 94.8%; single: n=131, 61.5%) and 171 adults in experiment 2 (females: n=106, 62.0%; mean age 28 [SD 7] years; at least some college education: n=163, 95.3%; single: n=95, 55.6%). Influenza vaccination intention was stronger in the individual-value conditions than in the collective-value conditions (F3,166=4.96, P=.03, η2=0.03). The reverse result was found for the willingness to share provaccination messages (F3,165=6.87, P=.01, η2=0.04). Specifically, participants who received a message emphasizing collective value had a higher intention to share the message than participants who read a message emphasizing individual value (F3,165=6.87, P=.01, η2=0.04), and the perceived responsibility for message sharing played a mediating role (indirect effect=0.23, 95% lower limit confidence interval [LLCI] 0.41, 95% upper limit confidence interval [ULCI] 0.07). In addition, gain framing facilitated influenza vaccination intention more than loss framing (F3,166=5.96, P=.02, η2=0.04). However, experiment 2 did not find that message framing affected message-sharing willingness. Neither experiment found an interaction between value type and message framing. Conclusions Strengthened individual value rather than collective value is more likely to persuade Chinese adults to vaccinate. However, these adults are more likely to share a message that emphasizes collective rather than individual value, and the perceived responsibility for message sharing plays a mediating role.