Benchmarking the dental randomised controlled literature on MEDLINE

Abstract

Objective: To develop and implement MEDLINE search strategies that access the dental literature in each of seven dental disciplines; to estimate the availability of randomised controlled trials (RCT) in these disciplines that might be used to make clinical decisions; and to examine publication trends.

Study design: Search strategies based on Medical Subject Headings (MeSH) for endodontics, implant dentistry, oral surgery, oral medicine/radiology, orthodontics, periodontics and restorative dentistry were developed to examine MEDLINE. Publications were limited to studies in humans, the years 1990 to 2000, and multiple methods of ascertainment employed to identify RCT. Ascertainment methods included maximally sensitive, sensitive, MEDLINE publication type and specific search strategies. Publication trends were examined using one search methodology.

Results: In the period 1990–2000, the MEDLINE searches identified a substantial number of RCT that differed significantly from one another, in ascending order by search strategy: specific (1260)<MEDLINE RCT (2443)<sensitive (6006)<maximally sensitive (26808) [P<0.001 in analysis of variance (ANOVA)]. The number of RCT varied significantly between the dental disciplines. For example, using the MEDLINE RCT, in ascending order, the number of RCT were: implant dentistry (104)<endodontics (106)<orthodontics (198)<restorative dentistry (420)<oral surgery (438)<periodontics (983)<oral medicine/radiology (984) (P<0.001, ANOVA). Trends over the 10-year period indicate that the number of RCT is increasing substantially in the aggregate for dentistry, and for each dental discipline. The range is approximately 10–20% per year, depending on the search strategy.

Conclusions: The results indicate that, (1) there is a substantial clinical literature of RCT in MEDLINE for clinical and curricular decision making; (2) the increasing number of RCT suggests the need for computer-based clinical knowledge systems; and (3) the methods used here can be employed to identify the most current clinical RCT literature in each of the dental disciplines. The results, however, require two caveats. First, the search results vary significantly, based on the search strategy. Thus, the results can be expected to ‘bracket’ the real number. Second, a truer measure of the clinical utility of each citation will be achieved only by individually assessing the validity and clinical applicability of each article. Within these limitations, these findings provide an estimate of the availability of the dental discipline specific therapeutic literature, and have implications for educational, clinical, research and policy decision makers.