title: Modification of the asthma quality of life questionnaire (standardised) for patients 12 years and older.
abstract: BACKGROUND
  The age limit for some adult asthma clinical trials has recently been lowered to 12 years. In this study we have made minor modifications to the standardised version of the adult Asthma Quality of Life Questionnaire (AQLQ(S)) to make it valid for patients 12 years and older (AQLQ12+).
  
  
  METHODS
  We have used two clinical trial databases, in which the AQLQ12+ was used, to compare the measurement properties of the questionnaire in patients 12-17 years and patients 18 years and older. A total of 2433 patients (12-75 years), with current asthma and with data that could be evaluated both at randomisation and end of treatment, were included.
  
  
  RESULTS
  The analysis showed that internal consistency, responsiveness and correlations with other clinical indices were very similar in patients 12-17 years and patients 18 years and older.
  
  
  CONCLUSIONS
  The measurement properties of the AQLQ12+ are similar in adolescents and adults and therefore the instrument is valid for use in adult studies which include children 12 years and older.
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. juniper@qoltech.co.uk
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Juniper
authors.forename: Klas
authors.initials: K
authors.lastname: Svensson
authors.forename: Ann-Christin
authors.initials: AC
authors.lastname: Mörk
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Ståhl
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001249:Asthma / Q000188:drug therapy / Q000503:physiopathology* / Q000523:psychology; D001294:Attitude to Health; D001993:Bronchodilator Agents / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011594:Psychometrics / Q000295:instrumentation*; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires
chemical_list: D001993:Bronchodilator Agents