Background and Purpose-We sought to measure the overall rate of usage of tissue-type plasminogen activator (tPA) for ischemic stroke at academic medical centers, and to determine whether ethnicity was associated with usage. Methods-Between

Background and Purpose-Recruitment rate is a major determinant of the duration, cost, and feasibility of acute stroke trials. Methods-We performed a meta-analysis of all randomized, controlled trials of Ն300 subjects that were designed to evaluate the efficacy of a medical intervention for the treatment of acute ischemic stroke. Data about trial recruitment, organization, and inclusion/exclusion criteria were abstracted independently by 2 reviewers who applied predefined criteria. Recruitment efficiency was defined as the number of subjects enrolled per study center per month of recruitment. Results-Of 32 trials meeting inclusion criteria, the average recruitment efficiency was 0.79 subjects per center per month (range 0.08 to 3.7). Recruitment efficiency did not vary by geographic region (Pϭ0.36), but trials conducted in 1 country had more efficient recruitment than international studies (Pϭ0.03), and recruitment efficiency declined with each percentage increase in the total number of study centers (Pϭ0.002). The primary study entry criteria that predicted reduced recruitment efficiency were the maximum allowable time from stroke to study enrollment (Pϭ0.002) and the exclusion of mild strokes (Pϭ0.009). Trials with a treatment window Ͼ6 hours had approximately double the recruitment rates of trials that used treatment windows Յ6 hours (1.03 versus 0.52 patients per center per month). Conclusion-Recruitment rates for acute stroke trials are influenced by organizational structure and study entry criteria.Characterizing predictors of recruitment may help optimize future trial design. (Stroke. 2006;37:123-128.)

Background:To evaluate the accuracy of the DIAGNOdent laser device (DD) for detecting occlusal fissure caries when used by three groups of examiners. Methods: Three final-year dental students (S), three General Dental Practitioners (G), and three Academic Clinicians (A) individually examined the non-cavitated occlusal surfaces of 25 extracted permanent molars using visual inspection (VI) then DD assessments. The presence of caries was confirmed following tooth sectioning. A cut-off limit of 30 was used for the DD to avoid over-treatment in a low caries-risk situation. Results: For VI, individual examiner sensitivity (caries correctly diagnosed) ranged from 53 to 86 per cent, and specificity (sound teeth correctly diagnosed) ranged from 76 to 95 per cent, with low Kappa agreements. Group S achieved the highest sensitivity (80 per cent) and Groups G and A achieved the highest specificities (88 per cent). For DD, individual examiner sensitivity ranged from 19 to 77 per cent, and specificity from 71 to 97 per cent, with generally moderate Kappa agreements. Group A achieved the highest (67 per cent) and Group G the lowest (44 per cent) sensitivities, and Group G achieved the highest specificity (94 per cent). Conclusions: There were similar widely varying results for the two diagnostic methods and for the three groups of examiners. However, the relatively high sensitivities found with VI and specificities found with DD should avoid over-treatment in low caries-risk populations.