title: Evaluation of practice patterns for the care of open-angle glaucoma compared with claims data: the Glaucoma Adherence and Persistency Study.
abstract: OBJECTIVE
  To perform a chart review to measure the validity of large claims databases in estimating patient cooperation with eyedrop therapy and to assess physician adherence with guidelines for a preferred practice pattern (PPP) using a new metric.
  
  
  METHODS
  Claims database analysis, chart review, and telephone survey.
  
  
  METHODS
  From 10,260 persons who were recently prescribed a prostaglandin eyedrop for open-angle glaucoma (OAG), a sample of 300 charts (3650 visits) was selected for detailed abstraction.
  
  
  METHODS
  Database review of pharmacy refill, diagnostic testing, and visit information, with chart review of a sample of patients from the database and interviews with an overlapping sample of patients and physicians.
  
  
  METHODS
  The individual patient medication possession ratio (MPR), an index estimating the proportion of time that patients have prescribed drug available for use, frequency of examination findings present in charts, and associations between MPR and physician adherence to a PPP.
  
  
  RESULTS
  Chart data confirm that the claims database accurately identified the specific glaucoma eyedrop prescribed, but often identified long-term OAG patients as being new to treatment. Physicians frequently used billing codes for OAG in patients with normal visual field tests. Physicians varied dramatically in their adherence to the PPP, performing intraocular pressure measurements, disc evaluations and imaging, and visual field tests on 90% of OAG patients, but carrying out gonioscopy, central corneal thickness measurement, and setting of target intraocular pressure (IOP) on half of patients.
  
  
  CONCLUSIONS
  Large claims databases permit conclusions regarding patient cooperation with glaucoma eyedrop therapy, but they should be used cautiously in imputing severity of disease and prior treatment history. Physician adherence to practice guidelines varied substantially; thus, scoring systems for physician behavior have promise in measuring outcome improvements related to better care.
authors.affiliation: Glaucoma Service and Dana Center for Preventive Ophthalmology, Wilmer Ophthalmological Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. hquigley@jhmi.edu
authors.forename: Harry A
authors.initials: HA
authors.lastname: Quigley
authors.forename: David S
authors.initials: DS
authors.lastname: Friedman
authors.forename: Steven R
authors.initials: SR
authors.lastname: Hahn
mesh_terms: D000577:Amides / Q000008:administration & dosage; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D000069580:Bimatoprost; D003008:Cloprostenol / Q000008:administration & dosage / Q000031:analogs & derivatives; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D004363:Drug Utilization / Q000706:statistics & numerical data*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis / Q000188:drug therapy*; D019983:Guideline Adherence / Q000706:statistics & numerical data; D006302:Health Services Research; D006306:Health Surveys; D006801:Humans; D007345:Insurance Claim Review / Q000706:statistics & numerical data*; D007429:Intraocular Pressure; D000077338:Latanoprost; D008055:Lipids / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions / Q000008:administration & dosage; D009898:Optic Disk / Q000473:pathology; D009901:Optic Nerve Diseases / Q000175:diagnosis; D010349:Patient Compliance / Q000706:statistics & numerical data*; D017410:Practice Guidelines as Topic / Q000592:standards; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D011461:Prostaglandins F, Synthetic / Q000008:administration & dosage; D000069557:Travoprost; D014481:United States; D014794:Visual Fields
chemical_list: D000577:Amides; D000959:Antihypertensive Agents; D008055:Lipids; D009883:Ophthalmic Solutions; D011461:Prostaglandins F, Synthetic; D003008:Cloprostenol; D000077338:Latanoprost; D000069580:Bimatoprost; D000069557:Travoprost