The factor structure of the revised Illness Perception Questionnaire in a population of oesophageal cancer survivors

Objectives: To determine whether the proposed seven-factor structure of the Illness Perception QuestionnaireRevised (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 (n52185) 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. Copyright (C) 2011 John Wiley & Sons, Ltd.