title: High agreement between parental reported inhaled corticosteroid use and pharmacy prescription data.
abstract: OBJECTIVE
  This study was conducted to assess the validity of parental reported use of inhaled corticosteroids (ICS) in children.
  
  
  METHODS
  ICS users were identified within the Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort study and the PIAMA pharmacy sub-cohort which is nested within the PIAMA study. Complete medication histories were available for the first 8 years of life for children within the PIAMA pharmacy sub-cohort. Parental reported ICS use was measured by using data from questionnaires. ICS use in the pharmacy records was determined by using the Anatomical Therapeutic Chemical (ATC) codes. The proportion of overall agreement and kappa statistics with their corresponding 95% confidence intervals were calculated to quantify agreement between self-reported medication use and pharmacy prescription data.
  
  
  RESULTS
  At all ages overall agreement was very high (>97%) and Cohen's kappa's ranged from 0.80 to 0.88 which also reflects excellent agreement between parental reported use of ICS and pharmacy prescription data.
  
  
  CONCLUSIONS
  Our finding suggests that parental report of medication use is a reliable source of data to asses ICS use in children. The questionnaire-based medication data collected within the PIAMA study can be used to study asthma medication use in a large group of children.
authors.affiliation: Division of Pharmacoepidemiology & Pharmacotherapy, Faculty of Science, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, the Netherlands.
authors.forename: Ellen S
authors.initials: ES
authors.lastname: Koster
authors.forename: Alet H
authors.initials: AH
authors.lastname: Wijga
authors.forename: Jan A M
authors.initials: JA
authors.lastname: Raaijmakers
authors.forename: Gerard H
authors.initials: GH
authors.lastname: Koppelman
authors.forename: Dirkje S
authors.initials: DS
authors.lastname: Postma
authors.forename: Marjan
authors.initials: M
authors.lastname: Kerkhof
authors.forename: Maarten O
authors.initials: MO
authors.lastname: Hoekstra
authors.forename: Johan C
authors.initials: JC
authors.lastname: de Jongste
authors.forename: Henriëtte A
authors.initials: HA
authors.lastname: Smit
authors.forename: Bert
authors.initials: B
authors.lastname: Brunekreef
authors.forename: Anke-Hilse
authors.initials: AH
authors.lastname: Maitland-van der Zee
mesh_terms: D000280:Administration, Inhalation; D000367:Age Factors; D001249:Asthma / Q000188:drug therapy*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003157:Community Pharmacy Services / Q000706:statistics & numerical data; D003625:Data Collection; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D010290:Parents; D011446:Prospective Studies; D011795:Surveys and Questionnaires
chemical_list: D005938:Glucocorticoids