Benchmarking the clinical orthodontic evidence on Medline

The purpose of this study was to identify and quantify the availability of orthodontic literature for evidence-based clinical decision-making (ie, sound clinical studies of etiology, diagnosis, treatment, or prognosis meeting basic methodologic criteria for direct clinical use). This is a first step toward developing online decision analysis systems. A search strategy based on Medical Subject Headings (MeSH) for orthodontics was developed to examine MEDLINE using the Ovid Web Gateway search engine. Sensitive and specific methodologic search filters were then employed to identify the 4 categories of information. The results were then subdivided by year to identify trends and sorted to identify source of publications. In the period 1990 to 1998, the MEDLINE searches identified 6938 English-language articles about orthodontics. The mean number of articles (+/-SD) per year ranged from 42+/-25 for specific searches to 314+/-214 for sensitive searches. The number of articles identified by the specific or sensitive searches increased 14% to 21% annually. When subdivided by clinical category, the mean numbers of articles per year for specific and sensitive searches were respectively: etiology 19+/-15 and 91+/-37, diagnosis 11+/-5 and 80+/-35, therapy 3+/-1 and 50+/-23, and prognosis 10+/-7 and 93+/-33. Five dental journals accounted for nearly half of these publications. These results provide several key findings: (1) there is a substantial literature of clinically relevant information in orthodontics upon which to base clinical decisions; (2) the information appears to be balanced between etiology, diagnosis, treatment, and prognosis; (3) approximately 45% of the articles reside in 5 journals, whereas the remainder reside in approximately 66 other journals, making it difficult to stay current; (4) the number of articles is increasing significantly each year; (5) to stay current, one would need to read between 1 and 6 articles per week, 52 weeks per year; (6) these trends suggest the need for computer-based clinical knowledge systems; and (7) the methods used here can be immediately employed to identify the best and most current clinical orthodontic evidence.