Background: Clear, transparent and sufficiently detailed abstracts are important because readers often base their initial assessment of a trial on such information. Objectives: To evaluate abstracts for reports of randomized trials, published in five high-impact journals, following publication of CONSORT for Abstracts guidelines (January 2008) and to assess its influence on editorial polices. Design: We selected a random sample of 30 primary reports of randomized trials per journal per year from Annals of Internal Medicine, BMJ, Lancet, JAMA and NEJM in 2007, 2008 and 2009 if indexed in PubMed with an electronic abstract. Secondary publications and economic analyses were excluded. Two authors extracted data independently using the CONSORT for Abstracts checklist. Data were analysed using STATA; 2007 and 2008 data are reported here, data for 2009 will be presented at the Colloquium. Results: 284 abstracts were assessed (median participants per trial 571 (IQR 251 to 2005)). Most abstracts described the study as randomized in the title (216; 76%), and reported participant eligibility (256; 90%), interventions (218; 77%), objectives (274; 97%), primary outcome (201; 71%), result for each group with effect size (211; 74%) and precision (225; 79%). Allocation concealment (13; 5%), sequence generation (7; 2%), and specific details on who was blinded (12; 4%) were poorly reported; as were trial design (65; 23%), funding source (3; 1%), harms (119; 42%), and number of participants randomized (137; 48%) and analysed (92; 32%) in each group. There were substantial differences in the median proportion of CONSORT items reported across journals perhaps reflecting different editorial policies. Conclusions: Abstracts of randomized trials continued to fail to meet a number of recommendations in the CONSORT for Abstracts guidelines until at least the end of 2008. We hope that recent endorsement of the guidelines by the International Committee of Medical Journal Editors will herald improvements.