In clinical trials where patients are randomized between two treatment arms, not all patients comply with the treatment they were randomly assigned to. The reasons for (non)compliance may be associated with the outcome variable and thereby act as confounders. The standard way of analysing such trial
The problem of measurement error in modelling the effect of compliance in a randomized trial
โ Scribed by Graham Dunn
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 154 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0277-6715
No coin nor oath required. For personal study only.
โฆ Synopsis
This paper explores the implications of measurement error in the analysis of compliance}response relationships in data from randomized trials. Given that compliance measures are rarely, if ever, error-free indicators of exposure it is argued that both the designs for the collection of compliance data and the statistical models for their resulting analysis should be changed to take the possibility of measurement error into account. An analysis which ignores measurement error in the compliance measurements will provide biased estimates of compliance}response relationships. Provided that one has two or more indicators of compliance for each subject, more appropriate models can be "tted using covariance structure modelling software. If one wishes to explore interactions from repeated measures data on both compliance and response then it is also important that one recognizes that the response measures are also error-prone and that they too are dealt with appropriately.
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