๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

Measurement error in epidemiology: the design of validation studies I: univariate situation

โœ Scribed by M. Y. Wong; N. E. Day; S. A. Bashir; S. W. Duffy


Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
124 KB
Volume
18
Category
Article
ISSN
0277-6715

No coin nor oath required. For personal study only.

โœฆ Synopsis


It is becoming standard practice in epidemiology to adjust relative risk estimates to remove the bias caused by non-di!erential errors in the exposure measurement. Estimation of the correction factor is often based on a validation study incorporating repeated measures of exposure, which are assumed to be independent. This assumption is di$cult to verify and often likely to be false. We examine the e!ect of departures from this assumption on the correction factor estimate, and explore the design of validation studies using two or even three di!erent types of measurement of exposure, where assumption of independence between the measures may be more realistic. The value of good biomarker measures of exposure is demonstrated even if they are feasible to use only in a validation study.


๐Ÿ“œ SIMILAR VOLUMES


Measurement error in epidemiology: the d
โœ M. Y. Wong; N. E. Day; N. J. Wareham ๐Ÿ“‚ Article ๐Ÿ“… 1999 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 129 KB ๐Ÿ‘ 2 views

The bias in relative risk estimates caused by errors in measurement of the relevant exposure is being increasingly recognized in epidemiology. Estimation of the necessary correction factor to remove this bias for univariate exposure has been considered in an earlier paper. We consider here the multi

Re-calculating the sample size in intern
โœ Meinhard Kieser; Tim Friede ๐Ÿ“‚ Article ๐Ÿ“… 2000 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 161 KB ๐Ÿ‘ 1 views

When designing a clinical trial, there is usually some uncertainty about the variability of the primary outcome variable. This may lead to an unnecessarily high or inadequately low sample size. The internal pilot study approach uses data from patients recruited up to an interim stage to re-estimate