A METHOD FOR DETERMINING THE SIZE OF INTERNAL PILOT-STUDIES

Authors
SANDVIK L ERIKSSEN J MOWINCKEL P RODLAND EA
Citation
L. Sandvik et al., A METHOD FOR DETERMINING THE SIZE OF INTERNAL PILOT-STUDIES, Statistics in medicine, 15(14), 1996, pp. 1587-1590
Citations number
3
Categorie Soggetti
Statistic & Probability","Medicine, Research & Experimental","Public, Environmental & Occupation Heath","Statistic & Probability","Medical Informatics
Journal title
Statistics in medicine → ACNP
ISSN journal
02776715
Volume
15
Issue
14
Year of publication
1996
Pages
1587 - 1590
Database
ISI
SICI code
0277-6715(1996)15:14<1587:AMFDTS>2.0.ZU;2-8
Abstract
The assessment of sample size in clinical trials comparing population means requires a variance estimate of the main efficacy variable. When this variance estimate has a low precision, it may be appropriate to use the data from the first patients entered in the trial ('internal p ilot study') to estimate the sample size. We suggest a method for dete rmining the size of internal pilot studies, which aims at ensuring tha t this size is as large as possible, but not larger than 'the optimal size' of the planned study. Advantages and limitations of the method a re discussed.