A multi-center evaluation of the McGill Pain Questionnaire: results from more than 1700 chronic pain patients.
We argue that the conflicting results reported in previous studies examining the factor structure of the McGill Pain Questionnaire Pain Rating Index (PRI) can be explained by differences in the patient samples and statistical analyses used across studies. In an effort to clarify the factor structure of the PRI, 3 different factor models were compared using confirmatory factor analysis in 2 samples of low-back pain patients (N = 1372) and in a third sample of patients suffering from other chronic pain problems (N = 423). A 4-factor model, similar to those obtained in previous studies where multiple criteria were used to determine the number of factors extracted, best explained covariation among PRI subclasses. However, relatively high interfactor correlations (approximately two-thirds of the variance explained by the best fitting factor structure was common variance) cast doubt on the discriminant validity of PRI subscales; examination of relationships between the PRI and MMPI subscales also failed to provide evidence of the discriminant validity or clinical utility of PRI subscales. Reducing the information from the 10 PRI sensory subclasses to a single subscale score may seriously limit the usefulness of the PRI. Alternate methods of using PRI data are suggested.
Holroyd
Kenneth A
KA
Department of Psychology, Ohio University, Athens, OH 45701 USA Duke University Medical Center, Durham, NC 27710 USA Department of Psychiatry and Behavioral Sciences and Department of Rehabilitation Medicine, University of Washington School of Medicine, Seattle, WA 98195 USA Department of Psychiatry and Behavioral Medicine, Bowman Gray School of Medicine, Winston-Salem, NC 27103 USA Department of Psychiatry, University of Tennessee Center for Health Sciences, Memphis, TN 38104 USA Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA 98195 USA Health Psychology Department, J. Leonard Camera Rehabilitation Center, The Industrial Commission of Ohio, Columbus, OH 43221 USA Department of Psychiatry, Ohio State University Medical School, Columbus, OH 43210 USA.
Holm
Jeffrey E
JE
Keefe
Francis J
FJ
Turner
Judith A
JA
Bradley
Laurence A
LA
Murphy
William D
WD
Johnson
Patrick
P
Anderson
Karen
K
Hinkle
Andrew L
AL
O'Malley
Brian W
BW
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001416:Back Pain / Q000175:diagnosis / Q000523:psychology; D002908:Chronic Disease; D005163:Factor Analysis, Statistical; D006801:Humans; D008950:MMPI; D008875:Middle Aged; D010146:Pain / Q000175:diagnosis / Q000523:psychology*; D010147:Pain Measurement / Q000379:methods*; D011795:Surveys and Questionnaires