Development and use of a taxonomy to carry out a systematic review of the literature on methods described to effect distal movement of maxillary molars.

OBJECTIVE To devise a taxonomy for the assessment of the orthodontic literature on methods described to effect distal movement of maxillary molars, to test the taxonomy for inter-assessor reliability, and to use it to classify studies in a systematic review of the literature. DATA SOURCES Articles appearing in the American Journal of Orthodontics and Dentofacial Orthopedics, Angle Orthodontist, (British) Journal of Orthodontics, European Journal of Orthodontics, and the Journal of Clinical Orthodontics between 1988 and 1998. Data selection Articles describing or evaluating the effect of appliances known or thought to have a distalizing effect on maxillary molars. DATA EXTRACTION A taxonomy was designed, tested by two reviewers independently to assess levels of agreement, and then used to record the features of the articles in a systematic review of the literature. DATA SYNTHESIS Kappa scores were used to assess the level of agreement between reviewers and found to be satisfactory. Studies were grouped according to study design and features of their methodology quantified. CONCLUSIONS Having devised and tested the taxonomy, we found that the quality of evidence for any method of moving maxillary molars distally was not high.