title: Idiopathic Pulmonary Fibrosis in United States Automated Claims. Incidence, Prevalence, and Algorithm Validation.
abstract: BACKGROUND
  Estimates of idiopathic pulmonary fibrosis (IPF) incidence and prevalence from electronic databases without case validation may be inaccurate.
  
  
  OBJECTIVE
  Develop claims algorithms to identify IPF and assess their positive predictive value (PPV) to estimate incidence and prevalence in the United States.
  
  
  METHODS
  We developed three algorithms to identify IPF cases in the HealthCore Integrated Research Database. Sensitive and specific algorithms were developed based on literature review and consultation with clinical experts. PPVs were assessed using medical records. A third algorithm used logistic regression modeling to generate an IPF score and was validated using a separate set of medical records. We estimated incidence and prevalence of IPF using the sensitive algorithm corrected for the PPV.
  
  
  RESULTS
  We identified 4,598 patients using the sensitive algorithm and 2,052 patients using the specific algorithm. After medical record review, the PPVs of these algorithms using the treating clinician's diagnosis were 44.4 and 61.7%, respectively. For the IPF score, the PPV was 76.2%. Using the clinical adjudicator's diagnosis, the PPVs were 54 and 57.6%, respectively, and for the IPF score, the PPV was 83.3%. The incidence and period prevalences of IPF, corrected for the PPV, were 14.6 per 100,000 person-years and 58.7 per 100,000 persons, respectively.
  
  
  CONCLUSIONS
  Sensitive algorithms without correction for false positive errors overestimated incidence and prevalence of IPF. An IPF score offered the greatest PPV, but it requires further validation.
authors.affiliation: 1 Safety and Epidemiology, HealthCore, Inc, Andover, Massachusetts.
authors.forename: Daina B
authors.initials: DB
authors.lastname: Esposito
authors.affiliation: 1 Safety and Epidemiology, HealthCore, Inc, Andover, Massachusetts.
authors.forename: Stephan
authors.initials: S
authors.lastname: Lanes
authors.affiliation: 1 Safety and Epidemiology, HealthCore, Inc, Andover, Massachusetts.
authors.forename: Macarius
authors.initials: M
authors.lastname: Donneyong
authors.affiliation: 1 Safety and Epidemiology, HealthCore, Inc, Andover, Massachusetts.
authors.forename: Crystal N
authors.initials: CN
authors.lastname: Holick
authors.affiliation: 2 Pulmonary and Critical Care, Tulane University School of Medicine, New Orleans, Louisiana.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Lasky
authors.affiliation: 3 Division of Pulmonary, Allergy and Critical Care Medicine, Columbia University Medical Center, New York, New York.
authors.forename: David
authors.initials: D
authors.lastname: Lederer
authors.affiliation: 4 Lung Transplant and Advanced Lung Disease Programs, Inova Fairfax Hospital, Falls Church, Virginia.
authors.forename: Steven D
authors.initials: SD
authors.lastname: Nathan
authors.affiliation: 5 Patient-Reported Outcomes and.
authors.forename: Sean
authors.initials: S
authors.lastname: O'Quinn
authors.affiliation: 6 Clinical Development, MedImmune, Gaithersburg, Maryland.
authors.forename: Joseph
authors.initials: J
authors.lastname: Parker
authors.affiliation: 7 Observational Research Center, AstraZeneca, Gaithersburg, Maryland; and.
authors.forename: Trung N
authors.initials: TN
authors.lastname: Tran
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D015897:Comorbidity; D016208:Databases, Factual; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000453:epidemiology*; D015994:Incidence; D007345:Insurance Claim Review; D016015:Logistic Models; D008297:Male; D008499:Medical Records / Q000706:statistics & numerical data*; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D015203:Reproducibility of Results; D012189:Retrospective Studies; D017678:Sex Distribution; D014481:United States / Q000453:epidemiology
keywords: epidemiology; idiopathic pulmonary fibrosis; interstitial lung disease; validation