Assessment of health-related quality of life using the SF-36 in Chinese cervical spondylotic myelopathy patients after surgery and its consistency with neurological function assessment: a cohort study

Abstract

BackgroundWe aimed to calculate the responsiveness and statistically prove the reliability of the Medical Outcomes Study Short Form Health Survey (SF-36) in a prospective cohort study. We investigated the profile of mid-term health-related quality of life (QOL) outcome assessments after surgery for cervical spondylotic myelopathy (CSM) and determined the consistency of the SF-36 assessments of neurological function.MethodsA total of 142 consecutive patients with CSM who underwent surgery were enrolled in the study. QOL and neurological assessments were evaluated before and at 3 months, 1 year, and more than 2 years postoperatively. We subsequently analyzed the reliability and responsiveness of the SF-36 and the QOL profile for its consistency regarding the neurological function assessment.Results(1) Cronbach’s α ranged from 0.73 (for role-emotional) to 0.85 (for physical function). The effect size ranged from 0.57 to 0.93 for SF-36’s eight scales. Minimum clinically important differences (MCIDs) in the physical scores (PCS) and mental scores (MCS) were 5.52 and 3.43, respectively. (2) The scores for all SF-36 scale sections indicated that patients with CSM were significantly impaired compared with healthy adults. SF-36 PCS and MCS peaked at 17.7 and 18.9 months after surgery, respectively. (3) At 3 months after surgery, improvements in the modified Japanese Orthopaedic Association (mJOA) scores significantly correlated only with patients’ physical function and bodily pain scores. At 1 year after surgery, improvements in the mJOA scores significantly correlated with physical function, general health, social function, and role-emotional. At the final follow-up, improvements in the mJOA scores significantly correlated with physical function, vitality, and role-emotional.ConclusionsSF-36 is reliable and has moderate responsiveness for evaluating patients with CSM, with MCID at 5.52 for the PCS and at 3.43 for the MCS. The preoperative QOL of the CSM patients was severely impaired compared with that of the normal population. Postoperatively, each SF-36 domain improved to a variable degree. During the early stage of recovery the mJOA score improvements correlated with SF-36’s physical component domains, whereas during the later stages the improvements were associated with the mental component domains.

Changes in quality of life after elective surgery: an observational study comparing two measures

“…Similar to previous studies in both general[28, 29] and surgical populations [13, 30], which found a MCID of approximately five points, we calculated the MCID for PCS to be approximately four and MCS approximately six. While MCIDs are traditionally reported separately for PCS and MCS, the global assessment asks patients to rate their overall quality of life, not the physical or mental components.…”

Predictors associated with neurological recovery after anterior decompression with fusion for degenerative cervical myelopathy

“…We also found that the independent predictor of recovery rate after ADF was identi ed as PCS score. A cohort study that investigated the surgical results of cervical spondylotic myelopathy showed that the recovery rate improvements correlated with SF-36's physical component domains [22], although both anterior and posterior surgery scores were included for the analysis. Collectively, when performing ADF, it may be important to have a thorough understanding of the patient's physical functioning prior to surgery to accurately predict the postoperative neurological recovery.…”

Development and Assessment of the Quality of Life Instruments for Chronic Diseases-Gout(QLICD-GO) (V2.0)

“…Zhang [16] has recommended 0.70 as the minimal Cronbach's α coe cient of internal consistency that would indicate relatively good internal consistency reliability. The Cronbach's α coe cient of the speci c module was 0.81, and the split-half reliability was 0.65 in this study, indicating relatively good reliability of the speci c module.…”