Inaccessible novel questionnaires in published medical research: hidden methods, hidden costs.

Although critical analysis of survey research is limited when reviewers and readers cannot view a study's questionnaire, access to novel questionnaires used in published research has not been systematically examined. The authors identified publications reporting the results of novel questionnaires in three medical journals (JAMA, The New England Journal of Medicine, and The Lancet) in January 2000-May 2003 and searched portable document format (PDF) versions of the studies for the complete questionnaire or a Uniform Resource Locator (URL) providing access to the questionnaire. When the questionnaire was not provided in the publication or a published URL, the authors requested it from the corresponding author in writing up to three times over a 6-week period. Of 93 publications with novel questionnaires, four printed the questionnaire in the article and three provided online access. Corresponding authors failed to provide questionnaires for 37 of 81 (46%) studies. Novel questionnaires used in published research are frequently not available to readers or researchers. Policies that improve access to novel questionnaires will allow better assessment of study results, reduce duplicated efforts, and improve authorship attribution for questionnaire design.