Editor—The distinction between giving a general summary of trial results to study participants and providing them with their own trial results is not made clear in the paper by Dixon-Woods et al or the accompanying editorial.1,2 Investigators may provide patients with a summary of the trial results, but even if they do not they should be aware that study participants may access these results elsewhere. The provision of personalised trial results, and in particular treatment allocation (unblinding), is quite a different matter and much debated.3,4 This is the more likely of the two to result in emotional consequences for the participants.
In a large scale study of cardiovascular disease prevention in older patients conducted over five years,5 we pledged at the outset to provide all study participants with a lay summary of the general study results on the same day that the results were to be published, which was done. Unblinding of participants was considered a completely separate and potentially more problematic exercise.4 In designing our unblinding strategy we acknowledged the right of patients to know their treatment allocations and personal results in the study, and their equal right not to know.
At the end of the study in Scotland we sent all appropriate participants in the study (n = 2067) a brief questionnaire asking if they wished to be unblinded and if so whether this should be done by telephone or a face to face visit with our study nurses. Altogether 1492 questionnaires were returned, of which 850 requested face to face unblinding, 541 requested a telephone unblinding, and the remainder asked for no unblinding. Many more subjects in our study (67%) requested details about their participation than that reported in the ORACLE study (20%).1 This may be explained by differences in the demographics of our patient population, our longer follow-up period and important differences in the background disease being studied. Whatever the reason, we should be cautious in generalising these findings.
Any evaluations on the clinical trial methods for providing participants with trial results should acknowledge the important distinction noted above.
Competing interests: None declared.
References
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