In order to explore whether and how Jewish teachings influence the attitudes of strictly-orthodox Jews to clinical trials, 10 strictly-orthodox Jews were purposively selected and interviewed, using a semi-structured schedule. Relevant literature was searched for similar studies and for publications covering relevant Jewish teachings. Thematic analysis was used to analyse transcribed interviews and explore relationships between attitudes and Jewish teachings identified in the review. Participants’ attitudes were influenced in a variety of ways: by Jewish teachings on the over-riding importance of (...) preserving life—the need to avoid risks affecting life and health, while taking risks to preserve life—and the religious obligation to help others, as well as by previous experience. Attitudes mirrored those in the general population, enabling many participants to reach conclusions that did not differ materially from those of the general population or research ethics committees. (shrink)