Statistics review 4: sample size calculations

Crit Care. 2002 Aug;6(4):335-41. doi: 10.1186/cc1521. Epub 2002 May 10.

Abstract

The present review introduces the notion of statistical power and the hazard of under-powered studies. The problem of how to calculate an ideal sample size is also discussed within the context of factors that affect power, and specific methods for the calculation of sample size are presented for two common scenarios, along with extensions to the simplest case.

Publication types

  • Review

MeSH terms

  • Clinical Trials as Topic
  • Humans
  • Research Design
  • Respiratory Distress Syndrome / therapy
  • Sample Size*
  • Shock, Septic / drug therapy
  • Statistics as Topic*