Background: There is growing evidence that the quality of informed consent in clinical research is often sub-optimal. Aims: To explore the conformity of patient recruitment with recommended informed consent procedures among patients who were invited to participate in a clinical study at a general teaching hospital, and to examine the association between consent procedures and the patients' decision to participate. Design and Methods: All inpatients discharged during a 1-month period were invited to complete a mailed survey in which they reported whether they were invited to participate in a study and whether 13 recommended elements of informed consent actually occurred. Results: Among 1303 respondents, 265 (20.3%) reported that they had been invited to participate in a study, and 191 (72.1%) accepted. While the majority of potential participants were fully informed about practical issues related to the study (e.g. what their participation would consist in), <50% were informed of possible risks or benefits, and only 20% about the origin of the study funds. Only 60% reported satisfactory answers to items assessing the overall information process (e.g. explanations were easy to understand). Older and sicker patients reported lower levels of conformity with informed consent procedures, as did patients who refused to participate in a study. Conclusions: Our results confirm that informed consent procedures fail to meet standards for many patients. In particular, consent information should be adapted to the needs of older and sicker patients. Improving the quality of informed consent may increase patients' participation in clinical researc
