Composite Pain Index: Reliability, Validity, and Sensitivity of a Patient-Reported Outcome for Research.

Abstract

OBJECTIVE:

A single score that represents the multidimensionality of pain would be an innovation for patient-reported outcomes. Our aim was to determine the reliability, validity, and sensitivity of the Composite Pain Index (CPI).

DESIGN:

Methodological analysis of data from a randomized controlled, pretest/post-test education-based intervention study.

SETTING:

The study was conducted in outpatient oncology clinics.

SUBJECTS:

The 176 subjects had pain, were 52 ± 12.5 years on average, 63% were female, and 46% had stage IV cancers.

METHODS:

We generated the CPI from pain location, intensity, quality, and pattern scores measured with an electronic version of Melzack's McGill Pain Questionnaire.

RESULTS:

The internal consistency values for the individual scores comprising the CPI were adequate (0.71 baseline, 0.69 post-test). Principal components analysis extracted one factor with an eigenvalue of 2.17 with explained variance of 54% at baseline and replicated the one factor with an eigenvalue of 2.11 at post-test. The factor loadings for location, intensity, quality, and pattern were 0.65, 0.71, 0.85, and 0.71, respectively (baseline), and 0.59, 0.81, 0.84, and 0.63, respectively (post-test). The CPI was sensitive to an education intervention effect.

CONCLUSIONS:

Findings support the CPI as a score that integrates the multidimensional pain experience in people with cancer. It could be used as a patient-reported outcome measure to quantify the complexity of pain in clinical research and population studies of cancer pain and studied for relevance in other pain populations.

• Authors: Diana J Wilkie, Robert E Molokie, Marie L Suarez, Miriam O Ezenwa, Zaijie J Wang
• Journal: Pain medicine (Malden, Mass.) (Pain Med) Vol. 16 Issue 7 Pg. 1341-8 (Jul 2015) ISSN: 1526-4637 [Electronic] England
• PMID: 25712169 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Validation Study)
• Copyright: © 2015 American Academy of Pain Medicine.

Topics

• Adult
• Aged
• Female
• Humans
• Male
• Middle Aged
• Pain (diagnosis, physiopathology)
• Pain Measurement (methods, statistics & numerical data)
• Patient Outcome Assessment
• Reproducibility of Results
• Sensitivity and Specificity
• Severity of Illness Index
• Surveys and Questionnaires