Reliability and validity of the Polish version of the Core Outcome Measures Index for the neck.

PURPOSE: Patient reported outcome measures play an increasingly important role in the outcomes research. The Core Outcome Measures Index (COMI) is a short, multidimensional instrument initially developed for the use by patients with low back pain. This study is an evaluation of a Polish version of COMI adapted for neck pain. METHODS: One hundred twenty-three patients complaining of neck pain were enrolled. All of them completed a questionnaire booklet containing COMI-neck, Neck Disability Index and Likert-type questions regarding the frequency of use of pain medications and pain frequency. Ninety-eight patients returned the retest questionnaire. Data quality was also assessed. Assessment of psychometric properties included examination of data quality, construct validity, test-retest reliability and factor analysis. RESULTS: The quality of data was good with no missing answers and a little floor effect. Exploratory factor analysis revealed a single-factor structure. Reliability expressed as intraclass correlation coefficient was 0.88 (95% CI 0.84-0.92) for the overall COMI score and was generally good for most of individual core items. The minimum detectable change (MDC95%) was 1.97. CONCLUSION: This version of the COMI-neck is a valid and reliable instrument, with good psychometric properties. It can be recommended for Polish-speaking patients.

Validation and cross-cultural adaptation of the Polish version of the Oswestry Disability Index.

STUDY DESIGN: Validation of a translated, culturally adapted questionnaire. OBJECTIVE: To translate and culturally adapt a Polish version of the Oswestry Disability Index (ODI) and to validate its use in Polish patients. SUMMARY OF BACKGROUND DATA: The ODI is among the most popular questionnaires used to evaluate back pain-related disability. To our knowledge no validated Polish version of the index was available at the time our study was initiated. METHODS: The questionnaire was translated and culturally adapted by 2 independent translators and approved by expert committee. Final version was included in the booklet consisting in addition of a previously validated Roland-Morris disability questionnaire, VAS for low back and leg and 3 Likert scale questions (pain medications, pain frequency, disability). It was tested on 169 patients with chronic low back pain, 164 (97%) of them were enrolled, and 84 of 164 (53%) returned the completed retest booklet within 2 to 14 days after the baseline test. There were no differences between the 2 groups in demographic and clinical parameters. Test-retest reliability, internal consistency, and construct validity were investigated. RESULTS: The mean ODI (standard deviation [SD]) was 48.45 (18.94); minimum 2, maximum 94. The Cronbach α for baseline questionnaires (n = 164) was 0.90. Concurrent validity, measured by comparing ODI responses with the results of the Roland-Morris disability questionnaire score was very good (r = 0.607, P < 0.001). The correlation with VAS back was fair (r = 0.37, P < 0.001) and with VAS leg was good (r = 0.56, P < 0.001). The tested ODI had excellent test-retest reliability, the intraclass correlation coefficient was 0.97 and standard error of measurements was 3.54, the resulting minimal detectable changes at the 95% confidence level was 10. CONCLUSION: The results of this study indicate that the Polish version of the ODI is a reliable and valid instrument for the measurement of disability in Polish-speaking patients with lower back pain.

Cross-cultural adaptation and validation of the Polish version of the core outcome measures index for low back pain.

PURPOSE: The core outcome measures index (COMI) is a short, multidimensional outcome scale validated for the use by patients with spinal disorders. It is a recommended instrument in the Spine Society of Europe Spine Tango Registry. The purpose of this study was to produce a cross-culturally adapted and validated Polish COMI. METHODS: The cross-cultural adaptation was carried out using the established guidelines. One-hundred and sixty-nine patients with chronic low back pain were enrolled, 89 took part in the reproducibility part of the study. Data quality, construct validity and reproducibility were assessed. RESULTS: The quality of data was very good with very few missing answers and modest floor effect. Reliability expressed as intraclass correlation coefficient (ICC) was 0.90 (95 % CI 0.85-0.93) for the overall COMI score and for most of the individual core items. The minimum detectable change (MDC95%) was 1.79. CONCLUSIONS: The Polish version of COMI showed a favorable reproducibility similar to that of previously tested language versions. The COMI scores correlated sufficiently with existing measures. This version of the COMI is a valuable instrument for the use by Polish-speaking patients with spinal disorders.