Purpose: The aim of this systematic review was to assess the methodologic and statistical quality of prospective case series of treatment interventions of dental implant surgery and prosthodontics published between 2004 and 2008.
Materials and methods: Prospective case series were identified following detailed searches of the Medline, EMBASE, and CINAHL databases. Identified studies were independently assessed by two nonblinded reviewers for 10 key methodologic and statistical domains. Information was collected using a customized data collection sheet.
Results: The initial search yielded 1,484 studies. Following application of inclusion criteria, 31 prospective case series reports that did not present the same patient material were identified for this review. Interexaminer agreement was assessed for all domains (median kappa score, 0.84). All disagreements were resolved by discussion. The source of funding was unclear in 20 studies (65%). Treatment protocol was adequately described in 21 studies (68%), and eligibility criteria were adequately reported in 24 studies (77%). Only two studies (6.5%) tested the intraexaminer/interexaminer reliability of at least one outcome of interest. Inferential statistical analysis was presented in 21 studies. However, this analysis was only considered appropriate in 12 studies (57%). Confidence intervals were reported in four studies (13%).
Conclusions: Prospective case series of treatment interventions of dental implant surgery and Prosthodontics are poorly analyzed and rarely test the reliability of outcome measures. These particular studies have limited external validity and appear to provide little unbiased evidence to support clinical decision-making.