Abstract:
:This paper considers the impact of bias in the estimation of the association parameters for longitudinal binary responses when there are drop-outs. A number of different estimating equation approaches are considered for the case where drop-out cannot be assumed to be a completely random process. In particular, standard generalized estimating equations (GEE), GEE based on conditional residuals, GEE based on multivariate normal estimating equations for the covariance matrix, and second-order estimating equations (GEE2) are examined. These different GEE estimators are compared in terms of finite sample and asymptotic bias under a variety of drop-out processes. Finally, the relationship between bias in the estimation of the association parameters and bias in the estimation of the mean parameters is explored.
journal_name
Biometricsjournal_title
Biometricsauthors
Fitzmaurice GM,Lipsitz SR,Molenberghs G,Ibrahim JGdoi
10.1111/j.0006-341x.2001.00015.xsubject
Has Abstractpub_date
2001-03-01 00:00:00pages
15-21issue
1eissn
0006-341Xissn
1541-0420journal_volume
57pub_type
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