title: Identification of Dutch children diagnosed with atopic diseases using prescription data: a validation study.
abstract: OBJECTIVE
  The aim of this study is to validate medication proxies for the identification of children diagnosed with atopic disorders that can be applied in various types of epidemiological research.
  
  
  METHODS
  Records of 7439 children, aged between 0 and 10 years, in the period 2001 until 2010, were retrieved from the Registration Network Groningen database, a general practitioners database in the north-eastern part of the Netherlands. The sensitivity and positive predictive value (PPV) of 22 medication proxies for the identification of children diagnosed with atopic disorders (asthma, atopic dermatitis, and allergic rhinitis) were computed using the registered diagnoses as gold standards. In addition, different capture periods (1 year, half year, and length of study period) for the detection of prescriptions were tested for all the medication proxies.
  
  
  RESULTS
  The highest PPV (0.84, 95 % CI 0.81-0.87) in combination with a sufficient sensitivity value (0.54, 95 % CI 0.50-0.57) for the identification of children diagnosed with asthma was yielded for the medication proxy, ≥2 prescriptions for anti-asthma medication within 1 year, including 1 inhaled steroid. PPV and sensitivity were even higher in the age group 6-10 years. The proxies designed for the identification of children diagnosed with atopic dermatitis and allergic rhinitis yielded only high PPVs (≥0.75) in combination with low sensitivity values (≤0.22). Altering the capture period for the detection of prescriptions to half a year or the length of the study period only affected sensitivity values.
  
  
  CONCLUSIONS
  Children diagnosed with asthma can be identified reliably with a range of medication proxies. The use of prescription data for the identification of children diagnosed with atopic dermatitis and allergic rhinitis is questionable.
authors.affiliation: Department of PharmacoEpidemiology and PharmacoEconomics University Centre of Pharmacy, University of Groningen, P.O. Box XB45, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands. b.mulder@rug.nl.
authors.forename: B
authors.initials: B
authors.lastname: Mulder
authors.affiliation: Department of General Practice, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Groenhof
authors.affiliation: Department of PharmacoEpidemiology and PharmacoEconomics University Centre of Pharmacy, University of Groningen, P.O. Box XB45, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.
authors.forename: L I
authors.initials: LI
authors.lastname: Kocabas
authors.affiliation: Department of PharmacoEpidemiology and PharmacoEconomics University Centre of Pharmacy, University of Groningen, P.O. Box XB45, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.
authors.forename: H J
authors.initials: HJ
authors.lastname: Bos
authors.affiliation: Department of Pediatrics, Medical Centre Leeuwarden, H Dunantweg 2, 8934 AD, Leeuwarden, The Netherlands.
authors.forename: T W
authors.initials: TW
authors.lastname: De Vries
authors.affiliation: Department of PharmacoEpidemiology and PharmacoEconomics University Centre of Pharmacy, University of Groningen, P.O. Box XB45, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.|Department of Epidemiology, University Medical Centre Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB, Groningen, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Hak
authors.affiliation: Department of PharmacoEpidemiology and PharmacoEconomics University Centre of Pharmacy, University of Groningen, P.O. Box XB45, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.
authors.forename: Ccm
authors.initials: C
authors.lastname: Schuiling-Veninga
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D016208:Databases, Factual; D003876:Dermatitis, Atopic / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D004363:Drug Utilization / Q000706:statistics & numerical data; D058005:General Practitioners; D006633:Histamine Antagonists / Q000627:therapeutic use; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007223:Infant; D007231:Infant, Newborn; D009426:Netherlands / Q000453:epidemiology; D065631:Rhinitis, Allergic / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*
chemical_list: D000305:Adrenal Cortex Hormones; D018927:Anti-Asthmatic Agents; D006633:Histamine Antagonists; D007166:Immunosuppressive Agents
keywords: Asthma; Atopic diseases; Eczema; Hay fever; Prescriptions; Sensitivity; Specificity