title: Estimating incidence and prevalence rates of chronic diseases using disease modeling.
abstract: Morbidity estimates between different GP registration networks show large, unexplained variations. This research explores the potential of modeling differences between networks in distinguishing new (incident) cases from existing (prevalent) cases in obtaining more reliable estimates.
  
  
  
  Data from five Dutch GP registration networks and data on four chronic diseases (chronic obstructive pulmonary disease [COPD], diabetes, heart failure, and osteoarthritis of the knee) were used. A joint model (DisMod model) was fitted using all information on morbidity (incidence and prevalence) and mortality in each network, including a factor for misclassification of prevalent cases as incident cases.
  
  
  
  The observed estimates vary considerably between networks. Using disease modeling including a misclassification term improved the consistency between prevalence and incidence rates, but did not systematically decrease the variation between networks. Osteoarthritis of the knee showed large modeled misclassifications, especially in episode of care-based registries.
  
  
  
  Registries that code episodes of care rather than disease generally provide lower estimates of the prevalence of chronic diseases requiring low levels of health care such as osteoarthritis. For other diseases, modeling misclassification rates does not systematically decrease the variation between registration networks. Using disease modeling provides insight in the reliability of estimates.
authors.affiliation: , PO box 1 3720 BA, Bilthoven, The Netherlands. Hendriek.boshuizen@rivm.nl.|Biometrics, Wageningen University, PO Box 16 6700AA, Wageningen, The Netherlands. Hendriek.boshuizen@rivm.nl.
authors.forename: Hendrike C
authors.initials: HC
authors.lastname: Boshuizen
authors.affiliation: , PO box 1 3720 BA, Bilthoven, The Netherlands.
authors.forename: Marinus J J C
authors.initials: MJ
authors.lastname: Poos
authors.affiliation: Department of Family Medicine, Maastricht University, P.O. Box 616, 6200, MD, Maastricht, The Netherlands.|Department of Public Health and Primary Care, Academic Center for General Practice, Kapucijnenvoer 33, blok J, PB 7001, 3000, Leuven, KU, Belgium.
authors.forename: Marjan
authors.initials: M
authors.lastname: van den Akker
authors.affiliation: Department of Primary and Community Care, Radboud university medical center, Internal post ELG 117, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Kees
authors.initials: K
authors.lastname: van Boven
authors.affiliation: Netherlands Institute for Health Services Research (NIVEL), Otterstraat 118-124, P.O. Box 1568, 3500 BN, Utrecht, The Netherlands.
authors.forename: Joke C
authors.initials: JC
authors.lastname: Korevaar
authors.affiliation: Department of Public Health and Primary Care, Leiden University Medical Center, Postal zone V-0-P, PO-box 9600, 2300 RC, Leiden, The Netherlands.
authors.forename: Margot W M
authors.initials: MW
authors.lastname: de Waal
authors.affiliation: Department of Primary and Community Care, Radboud university medical center, Internal post ELG 117, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Marion C J
authors.initials: MC
authors.lastname: Biermans
authors.affiliation: , PO box 1 3720 BA, Bilthoven, The Netherlands.
authors.forename: Nancy
authors.initials: N
authors.lastname: Hoeymans
mesh_terms: D002908:Chronic Disease / Q000453:epidemiology* / Q000401:mortality; D003920:Diabetes Mellitus / Q000453:epidemiology / Q000401:mortality; D005260:Female; D058006:General Practice / Q000458:organization & administration / Q000706:statistics & numerical data; D006333:Heart Failure / Q000453:epidemiology / Q000401:mortality; D006801:Humans; D015994:Incidence; D008297:Male; D015233:Models, Statistical; D009426:Netherlands / Q000453:epidemiology; D020370:Osteoarthritis, Knee / Q000453:epidemiology / Q000401:mortality; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology / Q000401:mortality
keywords: Burden of disease; General practice registration; General practitioner; Incidence-prevalence-mortality model; Morbidity; Public health