The Lancet now incorporates statistical review of submitted papers which remain candidates for publication after conventional review. We summarise here criticisms noted by the statistical reviewers for 191 such papers received between November, 1990, and June, 1991. Only 54% of papers were deemed acceptable or acceptable after revision; the others were either recommended for rejection (14%) or for more substantial revision and re-review (32%). Descriptions of methods and of results were found inadequate in about half of the papers; about one-quarter of papers had inadequate abstracts and conclusions. Major errors of inference were made in 48 papers and went hand in hand with major criticisms of analysis or design in those papers. The natural focus of statistical review is whether conclusions drawn are justified by study design and statistical analysis. In this, there is room for improvement by authors.