Medical Affairs, Acorda Therapeutics, Ardsley, New York, USA.
BMJ Open. 2013 May 28;3(5):e002798. doi: 10.1136/bmjopen-2013-002798.
To map the 12-item Multiple Sclerosis Walking Scale (MSWS-12) onto the EuroQol 5-dimension (EQ-5D) health-utility index in multiple sclerosis (MS) patients participating in the North American Research Committee on Multiple Sclerosis (NARCOMS) registry.
Cross-sectional MSWS-12 to EQ-5D cross-walking analysis.
NARCOMS registry spring 2010 biannual update and supplemental survey.
North American patients completing both the MSWS-12 and the EQ-5D randomly split into derivation and validation cohorts.
Ordinary least squares regression was performed within the derivation cohort, with participants' EQ-5D as the dependent variable. Results of the MSWS-12 were input as independent variable(s) into six regression models. Model goodness-of-fit was subsequently assessed in the validation cohort using the mean absolute error (MAE), root mean square error (RMSE) and the adjusted R(2). The best performing model was refined in the entire cohort and utilised for additional analyses.
A total of 3505 NARCOMS participants were included. Their mean±SD EQ-5D and MSWS-12 scores were 0.74±0.18 and 50.8±33.5, respectively, and these assessments were found to be moderately correlated (r=-0.553, p<0.001). The model using all individual MSWS-12 item scores as independent variables was found to have the best fit (MAE=0.109±0.096, RMSE=0.145, adjusted R(2)=0.329). The percentage of EQ-5D estimates within 0.05 and 0.10 of the actual value were 30% and 61%, respectively. This mapping equation was more precise in patients with moderate mobility impairment (MAE=0.087±0.061 at patient-determined disease step (PDDS) of 3-6) and less precise in patients with no (MAE=0.141±0.128 at PDDS of 0-2) or severe mobility impairment (MAE=0.121±0.049 at PDDS ≥7).
The EQ-5D scores can be predicted using the MSWS-12 item scores with reasonable precision in North American patients with MS. Prediction estimates were more precise in patients with moderate mobility impairment.
将多发性硬化行走量表（MSWS-12）的 12 项内容映射到多发性硬化症患者（MS）的欧洲五维健康量表（EQ-5D）健康效用指数中，这些患者参与了北美多发性硬化症研究委员会（NARCOMS）的注册研究。
MSWS-12 到 EQ-5D 交叉行走分析的横断面研究。
NARCOMS 注册表 2010 年春季的两年期更新和补充调查。
北美患者同时完成 MSWS-12 和 EQ-5D，随机分为推导队列和验证队列。
在推导队列中进行普通最小二乘回归，以参与者的 EQ-5D 为因变量。将 MSWS-12 的结果作为自变量输入到六个回归模型中。随后在验证队列中使用平均绝对误差（MAE）、均方根误差（RMSE）和调整 R（2）评估模型的拟合优度。在整个队列中对表现最佳的模型进行了优化，并用于进一步分析。
共纳入 3505 名 NARCOMS 参与者。他们的 EQ-5D 和 MSWS-12 评分分别为 0.74±0.18 和 50.8±33.5，两者相关性中等（r=-0.553，p<0.001）。发现使用所有个体 MSWS-12 项目评分作为自变量的模型拟合效果最佳（MAE=0.109±0.096，RMSE=0.145，调整 R（2）=0.329）。EQ-5D 估计值与实际值相差 0.05 和 0.10 的百分比分别为 30%和 61%。该映射方程在中度运动障碍患者（在患者确定的疾病阶段（PDDS）为 3-6 时 MAE=0.087±0.061）中更准确，在无运动障碍（在 PDDS 为 0-2 时 MAE=0.141±0.128）或严重运动障碍（在 PDDS≥7 时 MAE=0.121±0.049）患者中则不太准确。
在北美 MS 患者中，使用 MSWS-12 项目评分可以合理准确地预测 EQ-5D 评分。在中度运动障碍患者中，预测估计更为准确。
