Health Information Framing, Source Characteristics, and Health Behavior Promotion

Health information can influence how people understand health risks, evaluate available options, and make health-related decisions. This prospective behavioral study will use an online questionnaire and a randomized parallel-group design to evaluate how different characteristics of health information affect health-related decision intention and behavioral responses.

The study consists of two connected components conducted in different participant populations and regions. The first component examines how the source and framing of vaccination-related information influence participants' evaluation, decision intention, trust, and subsequent behavioral choices. The second component examines how differently framed mental health information, source cues, and social norms influence mental health-related decision-making and help-seeking responses.

In each component, eligible participants will provide informed consent and will be randomly assigned through an online survey platform to one of several pre-specified information conditions or a comparison condition. Outcomes will be assessed through self-reported questionnaire measures and behavioral responses recorded by the survey platform, including the decision to view further information or proceed with an available follow-up action.

The study does not administer or evaluate the safety or efficacy of any drug, biological product, vaccine, or medical device. All study procedures will be conducted using a secure online platform in accordance with the approved study protocol and applicable ethical requirements.

Not reported in this registry record.

Not reported in this registry record.

Behavioral: AI-sourced gain-framed message (Component 1)

Not reported in this registry record.

Behavioral: AI-sourced loss-framed message (Component 1)

Not reported in this registry record.

Behavioral: AI-sourced normative message (Component 1)

Not reported in this registry record.

Behavioral: AI-sourced structured message (Component 1)

Not reported in this registry record.

Behavioral: AI-sourced expert-authority message (Component 1)

Not reported in this registry record.

Behavioral: Official gain-framed message (Component 1)

Not reported in this registry record.

Behavioral: Official loss-framed message (Component 1)

Not reported in this registry record.

Behavioral: Official normative message (Component 1)

Not reported in this registry record.

Behavioral: Official structured message (Component 1)

Not reported in this registry record.

Behavioral: Official expert-authority message (Component 1)

Not reported in this registry record.

Behavioral: Gain-framed peer message (Component 2)

Not reported in this registry record.

Behavioral: Gain-framed expert message (Component 2)

Not reported in this registry record.

Behavioral: Loss-framed peer message (Component 2)

Not reported in this registry record.

Behavioral: Loss-framed expert message (Component 2)

Not reported in this registry record.

Behavioral: Social-norm message (Component 2)

Not reported in this registry record.

Participants view an AI-sourced message emphasizing the benefits of vaccination.

Participants view an AI-sourced message emphasizing the risks of not being vaccinated.

Participants view an AI-sourced message emphasizing social or public-health approval of vaccination.

Participants view an AI-sourced message explaining vaccination and booking procedures in a structured format.

Participants view an AI-sourced message attributed to professional or expert authority.

Participants view an official message emphasizing the benefits of vaccination.

Participants view an official message emphasizing the risks of not being vaccinated.

Participants view an official message emphasizing social or public-health approval of vaccination.

Participants view an official message explaining vaccination and booking procedures in a structured format.

Participants view an official message attributed to professional or expert authority.

Participants view a gain-framed message emphasizing the benefits of mental health help-seeking, with peer social cues.

Participants view a gain-framed message emphasizing the benefits of mental health help-seeking, attributed to an expert source.

Participants view a loss-framed message emphasizing the risks of not seeking mental health support, with peer social cues.

Participants view a loss-framed message emphasizing the risks of not seeking mental health support, attributed to an expert source.

Participants view a message presenting help-seeking as a common and socially approved behavior.

Time frame: Immediately after exposure to the assigned health information condition (post-exposure questionnaire).

In the Hunan population, assessed immediately after exposure with one 5-point item: "I am willing to receive the HPV vaccine in the future." Responses range from

1 (strongly disagree) to 5 (strongly agree). Higher scores indicate stronger intention to receive the HPV vaccine.

Time frame: Immediately after exposure to the assigned health information condition (post-exposure questionnaire).

In Tongzhou students and primary caregivers, assessed using three 7-point items asking how likely the participant would be to seek help from a psychologist, a psychiatrist, and another doctor if experiencing persistent emotional distress or thoughts of self-harm. Scores range from 1 (definitely would not) to 7 (definitely would). The mean of the three items will be calculated; higher scores indicate stronger professional help-seeking intention.

Time frame: During the same online session immediately after exposure to the assigned health information condition.

In the Hunan population, a binary behavioral outcome recorded by the online questionnaire platform after exposure. A positive response is defined as either selecting direct booking at the first decision point or agreeing to provide contact information for HPV vaccination booking at the end of the booking pathway. Viewing information without proceeding to booking or providing contact information is not counted as a positive response.

Time frame: Immediately after exposure to the assigned health information condition.

In the Hunan population, assessed with five HPV-adapted Vaccine Trust Gauge items covering vaccine safety, protection against serious illness, relative health risk, benefits versus risks, and effectiveness. Responses will be scored in the direction of greater trust using the prespecified VTG scoring and missing response rules. The item mean will be rescaled to 0-100; higher scores indicate greater trust.

Time frame: Immediately after exposure to the assigned health information condition.

In the Hunan population, assessed with five Vaccine Trust Gauge-adapted items measuring trust in HPV vaccine recommendations from schools or official institutions, doctors or nurses, family or friends, classmates or peers, and social media. Responses will be scored using the same prespecified VTG rules. The item mean will be rescaled to 0-100; higher scores indicate greater trust.

Time frame: Immediately after exposure to the assigned health information condition.

In the Hunan population, assessed using seven HPV-adapted 7C vaccination- readiness items covering calculation, collective responsibility, confidence in the system, confidence in vaccine safety, social conformity, convenience or constraints, and complacency. Items will be reverse scored where required and averaged so that higher scores indicate greater vaccination readiness.

Time frame: Immediately after exposure to the assigned health information condition.

In the Hunan population, assessed using the mean of three 5-point Health Belief Model items representing perceived susceptibility to HPV infection. Items will be reverse scored as specified in the analysis plan so that higher scores indicate greater perceived susceptibility.

Time frame: Immediately after exposure to the assigned health information condition.

In the Hunan population, assessed using one reverse-scored 5-point Health Belief Model item concerning whether the health effects of HPV infection are not serious. The score will be transformed so that higher scores indicate greater perceived severity.

Time frame: Immediately after exposure to the assigned health information condition.

In the Hunan population, assessed using the mean of six 5-point Health Belief Model items concerning perceived drawbacks, cost, insufficient information, uncertain long-term side effects, sexual stigma, and sensitivity of the topic. Higher scores indicate greater perceived barriers to HPV vaccination.

Time frame: Immediately after exposure to the assigned health information condition.

In the Hunan population, assessed using the mean of two 5-point Health Belief Model items concerning exposure to media reports promoting HPV vaccination and the influence of a doctor's recommendation. Higher scores indicate stronger cues to action.

Time frame: Immediately after exposure to the assigned school-based health message.

In Tongzhou students and primary caregivers, assessed using the Help-Seeking dimension of the Universal Mental Health Literacy Scale for Adolescents (UMHL-A). Five applicable items are used in students and four in caregivers. Items are scored on a 5-point scale, averaged, and rescaled to 0-100. Higher scores indicate more favorable help-seeking attitudes.

Time frame: Immediately after exposure to the assigned school-based health message.

In Tongzhou students and primary caregivers, assessed using the three-item Stigma dimension of the Universal Mental Health Literacy Scale for Adolescents (UMHL-A). Items are scored on a 5-point scale, averaged, and rescaled to 0-100 in the direction of less stigmatizing and more favorable attitudes.

Time frame: Immediately after exposure to the assigned health information condition.

In the Hunan population, assessed using two post-exposure 5-point items asking whether the participant is willing to use an AI chatbot to obtain further HPV vaccination information and whether generative AI would be used as one source of HPV vaccination information. Both items will be coded in the direction of greater intention and averaged.

Time frame: Immediately after exposure to the assigned health information condition.

In Hunan and Tongzhou participants, assessed using the three-item Benevolence dimension of the Human-Generative AI Trust Scale, adapted to HPV vaccination or mental health information. The items assess whether generative AI acts in the participant's best interest, is willing to understand the participant's needs and preferences, and will help to the best of its ability. Items use a 5-point response scale and are averaged; higher scores indicate greater benevolence-based trust.

Time frame: Immediately after exposure to the assigned health information condition.

In Hunan and Tongzhou participants, assessed using the three-item Competence dimension of the Human-Generative AI Trust Scale. The items assess whether generative AI can effectively support the participant in understanding health information, performs well in providing health information support, and has the expected functions for that role. Items use a 5-point response scale and are averaged; higher scores indicate greater competence-based trust.

Time frame: Immediately after exposure to the assigned health information condition.

In Hunan and Tongzhou participants, assessed using the three-item Reciprocity or Dependency dimension of the Human-Generative AI Trust Scale. The items assess whether participants believe they can rely on generative AI, whether it can continue to support health decisions, and whether they refer to health information provided by generative AI. Items use a 5-point response scale and are averaged; higher scores indicate greater reciprocity-based trust.

Time frame: Immediately after exposure to the assigned school-based health message.

In Tongzhou students and primary caregivers, assessed immediately after exposure using the 10-item Connor-Davidson Resilience Scale (CD-RISC-10). Each item is scored from 0 (not true at all) to 4 (true nearly all the time). The 10 item scores are summed to a total score ranging from 0 to 40; higher scores indicate greater psychological resilience. If the online platform stores responses as 1-5, scores will be recoded to 0-4 before summation.

Research on Health Information Framework, Information Sources and Promotion of Health Behaviors