Cancer Literacy as an Essential Factor for Lifestyle Behavior Changes: An Observational and Interventional Study

The CLARO study aims to examine the most effective way to design information materials that can strengthen optimistic beliefs about cancer prevention and improve cancer literacy indirectly. Around 5,800 participants from the Stuttgart region in Germany will be contacted by postal mail and invited to take part in an online survey using the LimeSurvey®-System. Four different types of information materials, tested in a pilot study (2x2-design: text or animation-based / narrative or non-narrative), will be included in the survey. Participants will be randomly assigned to one of the four interventions or to a control group that will not receive any intervention (the control group will have access to all information materials after having completed the whole questionnaire). As an incentive, participants will receive 10€ via bank transfer upon completing the survey.

The online survey can be accessed through a unique link or QR code and is compatible with various electronic devices such as PCs, tablets, and smartphones. Reminders will be sent after one month and two months. Participants can also request a paper questionnaire if needed. We will make an effort to contact more people from districts with lower socioeconomic status. Furthermore, the study cover letter will disclose that all study participants will receive ten euros if they provide their bank details after completion of the study questionnaires. Participants will be redirected via a link to another LimeSurvey for this purpose.

The online questionnaire will be divided into two parts. The first part, which will assess sociodemographic information, questions on cancer literacy, and more, will take about 10 minutes. Subsequently, participants will be randomly assigned to one of the four intervention groups or to a control group. Reading or viewing the information materials will take about 5 minutes. In the second part of the questionnaire, participants will evaluate the information materials, assess intentions for health behaviors, and have access to further information materials (approximately 5 minutes). The control group will have access to all information materials after having completed the whole questionnaire.

The primary aims of the observational part of the study are, first, to assess levels of cancer literacy in a representative German population, including all four cancer literacy domains (i.e., access, understand, appraise, apply). Second, this study part aims to identify sociodemographic groups (e.g., defined by age, sex, sociodemographic background, educational level) showing significantly lower levels of cancer literacy. As a secondary aim, the observational part of the study determines levels of cancer prevention behaviors in Germany (i.e., smoking status, diet, alcohol consumption, and physical activity).

The primary aim of the interventional part of the study is to assess the effects of different health communication strategies (i.e., text or animation in non-narrative or narrative style) on the primary outcome of cancer prevention beliefs. The secondary aim is to examine health communication strategies in their effect on secondary outcomes, i.e., intention for cancer prevention behaviors.

Eligibility Criteria:
Inclusion Criteria:

* Between 18 and 70 years old
* Being able to speak and understand german

Exclusion Criteria:

* Not being able and willing to provide informed consent and complete questionnaires