Missing data

Altman, Douglas G.; Bland, J. Martin
February 2007
BMJ: British Medical Journal (International Edition);2/24/2007, Vol. 334 Issue 7590, p424
Academic Journal
The article discusses the issue of missing data in quantitative medical research. Where losses are expected, one should try to increase the sample size. Ways to handle missing data include eliminating from analysis variables which have missing values or eliminating individuals with incomplete data or estimation or imputation of the missing values. The greater the missing data instances, the higher the potential for biased results and the threat to the study's integrity. Causes of missing data include such circumstances as a postal questionnaire survey in which not all selected individuals respond or patients who are lost to follow-up before the end of the study.


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