RT Journal Article
SR Electronic
T1 Methodological issues in conducting and analyzing longitudinal observational studies in rheumatoid arthritis.
JF The Journal of Rheumatology
JO J Rheumatol
FD The Journal of Rheumatology
SP 30
OP 34
VO 69
A1 Deborah P M Symmons
YR 2004
UL http://www.jrheum.org/content/69/30.abstract
AB This article discusses 5 methodological issues that arise in the course of conducting longitudinal observational studies: generalizability, missing data, repeated measures on the same individual, measures taken at varying time points from symptom onset, and assessing the effect of treatment. Methods discussed include general estimating equations and propensity scores. The points are illustrated by examples from the Norfolk Arthritis Register dataset.