Format

Send to

Choose Destination
Fam Pract. 1998 Feb;15(1):80-3.

Trials which randomize practices I: how should they be analysed?

Author information

1
Division of General Practice and Primary Care, St George's Hospital Medical School, London, UK.

Abstract

BACKGROUND:

In some general practice intervention trials, patients must be randomized in practices rather than individually, and this must be taken into account in the analysis.

OBJECTIVES:

In this article we aim to show how failure to do this may lead to spurious statistical significance and CIs which are narrower than they should be, and to describe the use of summary measures for each practice as a simple method of analysis.

METHOD:

The statistical issues are demonstrated by an example of a trial in general practice.

DISCUSSION:

The choice of unit of analysis will be most important where there are large numbers of patients recruited from each practice or a high degree of variability between practices.

PMID:
9527302
DOI:
10.1093/fampra/15.1.80
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center