A CRITICAL-REVIEW OF PAPERS FROM CLINICAL CANCER-RESEARCH

A review of 75 original articles from clinical cancer research ill Nor way is presented. Articles published in 1993 and with at least one Nor wegian author were included in the review. Sixty papers were observati onal, whereas 15 were experimental. Of the observational studies 44 we re retrospective. Most of the papers concerned prognostic factors. Pri or hypotheses were explicitly defined in 16 papers only, and less than half of the articles described inclusion and exclusion criteria. Samp le size calculations were performed in four papers only. The choice of statistical method was considered to be suitable in 22 of the 58 arti cles presenting statistical inferences. Problems related to multiple s ignificance testing were rarely addressed, although the median number of p-values reported was as high as 8. Confidence intervals for main f indings were presented in 14 papers. For proper planning of studies, a s well as for analysis and interpretation of study results, statistica l advice is indeed required.