title: Response-shift bias and parent-reported quality of life in children with otitis media.
abstract: OBJECTIVE
  To validate the 6-item quality-of-life survey (OM-6) and to investigate response-shift bias regarding children with otitis media.
  
  
  METHODS
  Otorhinolaryngology department of a university hospital that serves the southernmost part of the Netherlands.
  
  
  METHODS
  Seventy-seven children (age range, 12-38 months) experiencing persistent otitis media with effusion and scheduled for placement of tympanostomy tubes.
  
  
  METHODS
  The OM-6 measures health-related quality of life in 6 domains: physical suffering, hearing loss, speech impairment, emotional distress, activity limitations, and caregiver concerns.
  
  
  METHODS
  Parents completed the OM-6 before surgery (pretest) and 6 weeks after surgery (posttest). At the posttest, parents also completed a retrospective version of the pretest (retrospective pretest).
  
  
  RESULTS
  For most items, the test-retest reliability was good (R>0.8). The internal consistency of the OM-6 was satisfactory (alpha =.79). The construct validity, determined by correlating the ear-related global quality-of-life measure and the OM-6 summary score, was fair (R = -0.77, P<.01). Prospective change in quality of life on the OM-6 ranged from moderate (standardized response mean >/=0.5) to large (standardized response mean >/=0.8). Response-shift bias was present at the group level (t = -3.3, P<.01). Retrospective change was significant for hearing loss (z = -3.3, P<.05) and ear-related global quality of life (z = -3.6, P<.05).
  
  
  CONCLUSIONS
  The validity of the OM-6 has been proved in a Dutch population. The data suggest that parents underestimate the seriousness of hearing loss and overestimate the quality of life of their child before surgery, indicating a response shift. Treatment results could lead parents to realize that the situation before surgery had been worse than they thought.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital of Maastricht, The Netherlands. ATI@skno.azm.nl
authors.forename: Angelique A
authors.initials: AA
authors.lastname: Timmerman
authors.forename: Lucien J C
authors.initials: LJ
authors.lastname: Anteunis
authors.forename: Cor M G
authors.initials: CM
authors.lastname: Meesters
mesh_terms: D002675:Child, Preschool; D005260:Female; D006311:Hearing Disorders / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007223:Infant; D008297:Male; D008876:Middle Ear Ventilation / Q000379:methods*; D010034:Otitis Media with Effusion / Q000150:complications / Q000628:therapy*; D010146:Pain / Q000453:epidemiology / Q000209:etiology; D011446:Prospective Studies; D011788:Quality of Life; D012189:Retrospective Studies; D013064:Speech Disorders / Q000453:epidemiology / Q000209:etiology; D011795:Surveys and Questionnaires