4. Design and Sample Size Issues: How Many Subjects Do I Need for My Study?
Published Online: 10 SEP 2009
DOI: 10.1002/9780470840481.ch4
Copyright © 2009 John Wiley & Sons, Ltd
Book Title
Quality of Life Outcomes in Clinical Trials and Health-Care Evaluation: A Practical Guide to Analysis and Interpretation
Additional Information
How to Cite
Walters, S. J. (2009) Design and Sample Size Issues: How Many Subjects Do I Need for My Study?, in Quality of Life Outcomes in Clinical Trials and Health-Care Evaluation: A Practical Guide to Analysis and Interpretation, John Wiley & Sons, Ltd, Chichester, UK. doi: 10.1002/9780470840481.ch4
Publication History
- Published Online: 10 SEP 2009
- Published Print: 25 SEP 2009
Book Series:
ISBN Information
Print ISBN: 9780470753828
Online ISBN: 9780470686140
- Summary
- Chapter
Keywords:
- method of statistical analysis and QoL data collected;
- sample size calculations for research protocols;
- significance tests, P-values and power;
- design and sample size issues;
- two independent group comparison;
- Community Postnatal Support Worker (CPSW) study;
- Natural logarithm of SF-36 Physical Functioning dimension;
- QoL outcomes condensed into binary or dichotomous categorical scale;
- sample size method with quality of life outcomes;
- standard deviation of QoL outcome
Summary
This chapter contains sections titled:
Summary
Introduction
Significance tests, P-values and power
Sample sizes for comparison of two independent groups
Choice of sample size method with quality of life outcomes
Paired data
Equivalence/non-inferiority studies
Unknown standard deviation and effect size
Cluster randomized controlled trials
Non-response
Unequal groups
Multiple outcomes/endpoints
Three or more groups
What if we are doing a survey, not a clinical trial?
Sample sizes for reliability and method comparison studies
Post-hoc sample size calculations
Conclusion: Usefulness of sample size calculations
Further reading