Evaluation of sampling methods in research reported in selected clinical nursing journals: implications for nursing practice

This article summarizes standards relating to sampling methodology, identifies deviations from these standards in research studies reported in selected clinical nursing journals, and provides suggestions for improving sampling methods to enhance the applicability of research for nursing practice. A random sample of 30 research reports published in 1986 in five clinical nursing journals was examined. Nearly 97 per cent of the published studies contained at least one major deficiency in sampling methodology. More than two thirds failed to describe the sampling frame, sample size, or number of refusals, withdrawals, and/or cases lost. Thirteen per cent did not report sampling methods. More than half made generalizations that were inappropriate for the sampling method used; 43 per cent did not acknowledge any limitations of their sample. Sample sizes were small, and statistical power to detect significant differences was low. These deficiencies in sampling procedures could detract from the value of the research that nurses are encouraged to use as a basis for practice. This article provides specific recommendations for remedying these deficiencies to help ensure the scientific merit of the research published for nursing practice.