Minimum important change values for pain and disability: which is the best to identify a meaningful response in patients with chronic nonspecific low back pain?

Establishing Responsiveness and Minimal Clinically Important Difference of Quebec Back Pain Disability Scale (Hindi Version) in Chronic Low Back Pain Patients Undergoing Multimodal Physical Therapy

Increasing emphasis is placed on physical functional measures to examine treatments for chronic low back pain (CLBP). The Quebec Back Pain Disability Scale (Hindi version) (QBPDS-H) has never been evaluated for responsiveness. The objectives of this study were to (1) examine the internal and external responsiveness of the Quebec Back Pain Disability Scale (Hindi version) (QBPDS-H) and (2) find out the minimal clinically important difference (MCID) and minimal detectable change (MDC) in the functional ability of patients with chronic low back pain (CLBP) undergoing multimodal physical therapy treatment. In this prospective cohort study, QBPDS-H responses were recorded at the baseline and after eight weeks from 156 CLBP patients undergoing multimodal physiotherapy treatment. To differentiate between the clinically unimproved (n = 65, age: 44.16 ± 11.8 years) and clinically improved (n = 91, age: 43.28 ± 10.7 years) scores of patients from the initial assessment to the last follow-up, the Hindi version of the Patient's Global Impression of Change (H-PGIC) scale was utilized. Internal responsiveness was large (E.S. (pooled S.D.) (n = 91): 0.98 (95% CI = 1.14-0.85) and Standardized Response Mean (S.R.M.) (n = 91): 2.57 (95% CI = 3.05-2.17)). In addition, the correlation coefficient and receiver operative characteristics (R.O.C.) curve were used to assess the QBPDS-H external responsiveness. MCID and MDC were detected by the R.O.C. curve and standard error of measurements (S.E.M.), respectively. The H-PGIC scale showed moderate responsiveness (ρ = 0.514 and area under the curve (A.U.C.) = 0.658; 95% CI, 0.596-0.874), while the MDC achieved 13.68 points, and the MCID was found have 6 points (A.U.C. = 0.82; 95% CI: 0.74-0.88, sensitivity = 90%, specificity = 61%). This study shows that QBPDS-H has moderate levels of responsiveness in CLBP patients receiving multimodal physical therapy treatment, so it can be used to measure the changes in disability scores. MCID and MDC changes were also reported with QBPDS-H.

Predictors of failure to achieve minimal clinical important difference for pain and disability after mechanical diagnosis and therapy (MDT)-based multimodal rehabilitation for neck pain: a retrospective analysis of 4998 patients

PURPOSE

To determine predictors of failure to achieve minimal clinical important difference (MCID) for pain and disability at discharge after mechanical diagnosis and therapy (MDT)-based multimodal rehabilitation for neck pain (NP).

METHODS

Pre- and post-treatment numerical pain rating scale (NPRS) and neck disability index (NDI) in patients with mechanical NP were analysed in this retrospective study. Multivariate analysis was performed to investigate the effect of covariates such as age, gender, lifestyle, body mass index, presentation, diabetes, osteoporosis, response to repeated movement testing, treatment sessions, compliance rate, and pre-treatment NPRS and NDI scores on failure to achieve MCID of ≥ 30% for NPRS and NDI scores post-treatment.

RESULTS

In the 4998 patients analysed for this study, 7% and 14.5% of patients failed to achieve MCID for NPRS and NDI scores, respectively, at the end of treatment. Age > 70 years, diabetes, osteoporosis, partial or non-response to repeated movements, lesser treatment sessions, and lower compliance rate were associated with increased risk for failure to achieve MCID for NPRS and NDI scores. A higher pre-treatment NDI score was associated with failure to achieve MCID for NPRS score, whereas lower pre-treatment NPRS and NDI scores were associated with failure to achieve MCID for NDI score.

CONCLUSION

Although MDT-based multimodal rehabilitation helped to achieve significant reduction in pain and disability in mechanical NP, several baseline risk factors were associated with failure to achieve MCID for pain and disability after treatment. Identifying and modifying these factors as part of rehabilitation treatment may help to achieve better outcomes in mechanical NP.