Clinical trials in orthodontics II: assessment of the quality of reporting of clinical trials published in three orthodontic journals between 1989 and 1998.

AIMS: To test the hypothesis that the quality of reporting of orthodontic clinical trials is insufficient to allow readers to assess the validity of the trial.

DESIGN: A retrospective observational study.

SETTING: The American Journal of Orthodontics and Dentofacial Orthopedics (AJODO), the British Journal of Orthodontics (BJO) and European Journal of Orthodontics (EJO).

DATA SOURCE: Clinical trials published between 1989 and 1998.

METHOD: A hand search was performed to identify all clinical trials. The concealment of allocation, whether the trial was randomized, double blind, and whether there was a description of withdrawals and dropouts was recorded.

RESULTS: One hundred and fifty-five trial reports were identified of which 4 (2.6%) were adequately concealed, 85 (54.8%) were described as being randomized, 10 (6.5%) as double-blind, and 44 (28.4%) gave a description of withdrawals and drop-outs from the trial. The type of randomization was considered appropriate in 78 (50.3%) reports and in 57 (36.8%) reports the level of blinding was considered appropriate. When assessed for the risk of bias in the reported trials,(1) one trial (0.6%) had a low risk of bias, 17 (11%) a moderate risk, and 137 (88.4%) a high risk.

CONCLUSIONS: In general the quality of reporting orthodontic clinical trials was insufficient to allow readers to assess the validity of the trials. Reporting of clinical trials could be improved by orthodontic journals adopting the CONSORT statement(2,)(3) to ensure that all relevant information is provided.