Structural validity of the Brazilian version of the Shoulder Pain and Disability Index in patients with chronic shoulder pain

The internal structure of Brazilian versions of disability questionnaires in patients with chronic low back pain: A cross-sectional study

BACKGROUND

Structural validity refers to the degree to which the scores of a questionnaire or scale are an adequate reflection of the construct to be measured. The aim of this study was to perform the analysis of the structural validity of the Roland-Morris Disability Questionnaire (RMDQ), Oswestry Disability Index (ODI), Quebec Back Pain Disability Scale (QBPDS), and Bournemouth Questionnaire (BQ) in Brazilian respondents with chronic low back pain.

METHODS

A cross-sectional study was conducted. The sample was composed by respondents with non-specific chronic low back pain (score ≥3 points on the 11-point Numerical Pain Rating Scale). The internal structure (number of domains and items) of the Brazilian versions of the RMDQ, the ODI, the QBPDS, and the BQ were analyzed by the confirmatory factor analysis.

RESULTS

Two hundred and twenty-two patients were included. Most of the sample consisted of women and overweight. The RMDQ and ODI have a one-dimensional structure and acceptable values for all confirmatory factor analysis fit indices. The QBPDS with 4 domains and 20 items showed the best values of the fit indices. In addition, we did not identify an internal structure for the BQ supported by the confirmatory factor analysis.

CONCLUSION

The ODI and RMDQ present valid internal structure with 1 domain (disability). The QBPDS has a valid internal structure with 4 domains (rest, prolonged postures, ambulation/reach, and bending/carrying). The BQ does not have a well-defined internal structure.

Brazilian version of the Neck Bournemouth Questionnaire does not have a well-defined internal structure in patients with chronic neck pain

OBJECTIVE

To investigate the structural validity of the Brazilian version of the Neck Bournemouth Questionnaire in patients with chronic neck pain.

DESIGN

Cross-sectional study.

SETTING

Community participants collected via online platform.

SUBJECTS

Participants with neck pain (minimal pain intensity of 3 points at rest on 11-point Numerical Rating Scale), both genders and aged ⩾18 years old.

MAIN MEASURE

The Numerical Rating Scale, Neck Disability Index, Pain-Related Catastrophizing Thoughts Scale, Tampa Scale of Kinesiophobia and the Neck Bournemouth Questionnaire were completed. Exploratory and confirmatory factor analyses were used to identify dimensionality and to compare different structures of the Neck Bournemouth Questionnaire.

RESULTS

We included 103 participants. The sample consisted mostly of adults (mean age = 33.64 years, standard deviation = 10.48 years), females (n = 82, 79.6%), lean, single and with higher education. The exploratory factor analysis with implementation of the parallel analysis identified the one-dimensional structure of the Neck Bournemouth Questionnaire, with a Kaiser-Meyer-Olkin value of 0.80 and Bartlett's test significant (P < 0.05). We observed that all structures tested in this study presented a high amount of residues in confirmatory factor analysis, which were identified by the value of root mean square error of approximation > 0.08 and chi-square/degree of freedom > 3.00.

CONCLUSION

The internal structure of the Brazilian version of the Neck Bournemouth Questionnaire is not clear and well-defined. It was not possible to identify the construct measured by the instrument in individuals with chronic neck pain.