|Title||An e-mail survey identified unpublished studies for systematic reviews.|
|Publication Type||Journal Article|
|Year of Publication||2006|
|Authors||Reveiz L, Cardona AF, Ospina EG, de Agular S|
|Journal||Journal of clinical epidemiology|
|Date Published||2006 Jul|
|Keywords||Cross-Sectional Studies; Electronic Mail; Evidence-Based Medicine; Humans; Information Storage and Retrieval; MEDLINE; Publishing; Randomized Controlled Trials as Topic; Research Design|
BACKGROUND AND OBJECTIVE: A large number of trials remain difficult to locate or unpublished for systematic reviews. The objective of this article was to determine the usefulness of making e-mail contact with authors of clinical trials and literature reviews found in MEDLINE to identify unpublished or difficult to locate Randomized Controlled Trials (RCTs).
MATERIALS AND METHODS: A structured search for detecting RCTs in MEDLINE was made from January 1999 to June 2003; a questionnaire was sent to a random sample of 525 author's mails. Those RCTs obtained were sought in MEDLINE, EMBASE, the Cochrane Controlled Trials Register, LILACS, and ongoing registers.
RESULTS: 40 (7.6%) replies were received; 10 previously undescribed and unpublished RCTs and 21 unregistered ongoing RCTs were found. The most frequently given reasons for not publishing were: lack of time for finalizing the statistical analysis and preparing the manuscript, contractual obligations with the pharmaceutical industry, methodologic errors in designing, and editorial rejection.
CONCLUSIONS: Using the e-mails of authors detected by the search in electronic databases could contribute toward detecting potentially relevant ongoing or unpublished RCTs enabling rapid, straightforward, low-cost systematic review; in addition, the results of this study support the need of universal registration of all studies at their inception.
|Alternate Journal||J Clin Epidemiol|