Abstract
Introduction
The importance of use of patient-reported outcome measurements (PROMs) in spine care has been previously widely reported, especially for lumbar conditions. One of the main clinicometric properties of a PROM is the responsiveness showing its discriminative ability between good and poor global treatment outcomes. Very limited data about the responsiveness of different cervical PROMs have been published so far. The aim of the study was to analyze the responsiveness of three validated cervical PROMs on a prospective clinical cohort.
Material and Methods
A total of 100 patients with degenerative cervical spinal disorders were recruited into the study. The patients filled out the cross-culturally adapted Hungarian versions of the Neck Disability Index (NDI), the Neck Pain and Disability Scale (NPAD), and the Core Outcome Measures Index for neck (COMI). Test–retest method was applied to assess the validity and reliability dimensions of the questionnaires. Patients completed the questionnaires 3 months after the surgical or nonsurgical treatment. Two different five-point Likert scales on global treatment outcome were used to determine the “good” and “poor” results. The receiver operating characteristics (ROC) method was used to evaluate the discriminative ability of the given change score relative to the outcome (c-index). SPSS 20.0 statistical program package was used for the analyses where p < 0.05 was considered significant.
Results
Correlation of the PROMs with pain was very good (r = 0.65, 0.73, and 0.79 for NDI, NPAD, and COMI, respectively). Intraclass correlation coefficient for the reliability measurement was high for all the three PROMs (ICC = 0.90, 0.85, and 0.89 for NDI, NPAD, and COMI, respectively) and the other clinicometric parameters showed good reliability and validity of the three PROMs in the test–retest phase of the study. For the question about the success of the applied treatment, the c-index was 0.66, 0.76, and 0.65 for NDI, NPAD, and COMI, respectively. When patients replied about the health of their cervical spine, the c-index proved to be 0.74, 0.85, and 0.68 for NDI, NPAD, and COMI, respectively.
Conclusion
Hungarian versions of NDI, NPAD, and COMI proved to be valid and reliable condition-specific measurements. The discriminative ability between “good” and “poor” global treatment outcome of the three PROMs was good, especially for the NPAD which performed significantly better in the responsiveness dimension than the other two PROMs. Based on our results, we can conclude that the use of condition-specific PROMs in cervical spine care is desirable but the performance of the PROMs can be different in certain clinicometric dimensions. Nevertheless, further studies considering the potential differences in different conditions and treatments are needed.