Background and objectives A donor health questionnaire (DHQ) aims to ensure the safety of donors and recipients of transfusions or transplantations with blood components, plasma-derived medicinal products, tissues, haematopoietic stem cells and medically assisted reproduction (in short substances of human origin; SoHO). Currently, many different DHQs exist across countries and SoHO. TRANSPOSE (TRANSfusion and transplantation PrOtection and SElection of donors) developed and validated a standardized DHQ to use across countries and SoHO. We tested whether participants understand the questions and provide honest answers.

Methods For the validation of the standardized DHQ, two demographically representative online surveys were conducted in Germany (N = 3329) and Austria (N = 3432). We surveyed whether participants understood each DHQ question and would answer the questions truthfully. We used experimental settings to test whether there is a difference between mode of administration (print vs. online), the order of the questions (subject vs. chronological order), and the positioning of the general state of health question (beginning vs. end) in the DHQ. Using regression models, we tested the DHQ's impact on participant mood after completion and on socially desirable response behaviour.

Results Participants understood the DHQ questions well and would answer them honestly. Nevertheless, the data show different levels of understanding and honesty when responding. Administration mode was the only characteristic that had a significant influence on mood, with the online version resulting in a more favourable mood in comparison to the printed version.

Conclusion The DHQ was well understood and had a low dishonest tendency. Our findings can serve as an impulse for further research on DHQ criteria across other SoHO and countries.