Background: The study was planned to determine the relationship of the Functional Rating Index (FRI) with disability, pain, and quality of life in patients with low back pain.
Material/methods: A total of 84 patients with low back pain, of whom 58 were women and 26 were men, with average age of 47.8 +/- 12.0 years participated in this study. The Functional Rating Index was used to determine the functional status of the patients. Disability was evaluated using the Roland-Morris Disability Questionnaire (RMQ), pain intensity was evaluated with the Visual Analog Scale (VAS), and the Short Form-36 (SF-36) was used to assess quality of life. The Pearson correlation coefficient was used for correlation of the FRI with the RMQ, VAS, and SF-36. The internal consistency for test-retest reproducibility of FRI was assessed with Cronbach's alpha.
Results: There was a strong positive correlation between the FRI and the RMQ (p < 0.05). It was found that an increase in severity of pain was associated with the FRI survey score (p < 0.05). There was a negative statistically significant correlation between the FRI and all parameters of SF-36 (p < 0.05). FRI demonstrated high internal consistency, with alpha = 0.960. The test-retest correlation was r = 0.926 (p = 0.000).
Conclusions: Our study reveals that the FRI, as a reliable instrument in assessing functional status, is associated with the RMQ, the VAS, and all items of the SF-36 in patients with LBP. It was concluded that changes in functional status were related to changes in disability, pain, and quality of life.