Musculoskeletal pain illness perceptions: factor structure of the Illness Perceptions Questionnaire-Revised

Area of Science:

• Psychological Medicine
• Health Psychology

Background:

• The Revised Illness Perceptions Questionnaire (IPQ-R) is a widely used tool for assessing illness perceptions.
• Its suitability for primary care musculoskeletal pain patients requires validation.

Purpose of the Study:

• To evaluate the psychometric properties of the IPQ-R in primary care patients with musculoskeletal pain.
• To determine if the IPQ-R's factor structure is appropriate for knee, hand, and back pain populations.

Main Methods:

• Confirmatory and exploratory factor analyses were conducted on data from 393 knee pain, 2113 hand pain, and 1591 back pain patients.
• Confirmatory factor analysis assessed the distinctness of seven IPQ-R dimensions.
• Exploratory factor analysis explored the structure of causal items.

Main Results:

• Confirmatory factor analysis revealed goodness-of-fit indices below established criteria.
• Removing six items improved model fit but did not meet criteria for good model fit.
• An interpretable factor structure for causal items could not be determined.

Conclusions:

• Limited evidence supports the distinctness of the IPQ-R's seven dimensions in this patient group.
• The structure of causal items within the IPQ-R remains unclear for primary care musculoskeletal pain patients.
• Further psychometric development of the IPQ-R is necessary for this population.