Abstract:
:To project national hepatitis C virus (HCV) burden, unbiased estimation of HCV progression to liver cirrhosis is required for the whole community of HCV-infected individuals. However, widely varying estimates of progression rates to cirrhosis have been produced. This disparity is partly associated with the statistical methods applied, but is mainly due to the differing types of study cohort. We use an inverse probability weighted estimation method to recover the true parameters for the (Weibull regression) model that determines the incubation period from infection to cirrhosis for the community of HCV-infected individuals, when there is cirrhosis-related recruitment bias to the studied cohort. We apply the method to simulated data for a liver clinic which attracts patients from a community of 1000 HCV-infected individuals under different event-biased referral patterns. We investigate how well the method performs in recovering the true community parameters, and then apply it to Edinburgh Royal Infirmary's liver clinic series. The results obtained are compared to those from a Weibull survival analysis which ignores the selection bias.
journal_name
Stat Methods Med Resjournal_title
Statistical methods in medical researchauthors
Fu B,Tom BD,Bird SMdoi
10.1177/0962280208094688subject
Has Abstractpub_date
2009-06-01 00:00:00pages
303-20issue
3eissn
0962-2802issn
1477-0334pii
0962280208094688journal_volume
18pub_type
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