title: The factor structure of the revised Illness Perception Questionnaire in a population of oesophageal cancer survivors.
abstract: OBJECTIVE
  To determine whether the proposed seven-factor structure of the Illness Perception Questionnaire—Revised (Timeline Acute/Chronic, Timeline Cyclical, Consequences, Personal Control, Treatment Control, Illness Coherence and Emotional Representations) is appropriate among a population of oesophageal cancer survivors.
  
  
  METHODS
  Everyone registered with the Oesophageal Patients' Association in the UK (n = 2185) was mailed a questionnaire booklet, which included the Illness Perception Questionnaire—Revised. Responses from 587 oesophageal cancer survivors (27%) were subjected to a confirmatory factor analysis.
  
  
  RESULTS
  The proposed seven-factor structure provided a reasonable fit of the data. Modification indices suggested that a significantly better fit could be provided if one of the items on the Timeline Acute/Chronic factor loaded on the Treatment Control factor and an error covariance was added between two other items on the Timeline Acute/Chronic factor.
  
  
  CONCLUSIONS
  The model fit for the seven-factor structure proposed by Moss-Morris et al. (Psychol Health 2002;17:1–16) was found to be adequate in our study. However, the structure of the timeline acute/chronic factor needs to be considered, particularly when the IPQ-R is to be used among older people with a potentially life-threatening illness or those receiving palliative care.
authors.affiliation: School of Psychology, Queen's University Belfast, Belfast, UK. m.dempster@qub.ac.uk
authors.forename: Martin
authors.initials: M
authors.lastname: Dempster
authors.forename: Noleen K
authors.initials: NK
authors.lastname: McCorry
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004938:Esophageal Neoplasms / Q000523:psychology*; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010465:Perception; D011594:Psychometrics / Q000295:instrumentation; D011795:Surveys and Questionnaires; D017741:Survivors / Q000523:psychology*