Reliability and validity of the German version of the Myositis Activities Profile (MAP) in patients with inflammatory myopathy

The Myositis Activity Profile (MAP) is the only disease-specific questionnaire to assess limitations in activities of daily living (ADL) in patients with inflammatory myopathy (IM). Because a German version does not currently exist, this study’s aim was to translate the MAP and assess reliability and construct validity of the new version. Therefore, a cross-cultural adaptation was performed following international guidelines. Forty-eight patients with IM completed the German-MAP, twice within two weeks. They were also assessed using the Health Assessment Questionnaire (HAQ), 36-Item Short Form Survey (SF36), Manual Muscle Test (MMT8), Quantitative Muscle Testing (QMT) and Functional Index (FI-2). For discriminant validity, 48 age-and gender-matched healthy controls completed the German-MAP. Reliability was assessed using weighted kappa (Kw). Correlations between the MAP and the HAQ, the physical (PCM) and mental (MCS) component scores of SF36 and the MMT8 and QMT muscle tests were assessed using Spearman correlation analysis. Discriminative validity was assessed by calculating the Area under the Curve (AUC). The German-MAP showed substantial reliability for the four subscales (Kw: 0.65–0.71) and moderate to substantial reliability for the single items (Kw: 0.57–0.77). The MAP showed good construct validity (high correlations with HAQ and PCM, moderate with FI-2, QMT and MMT8 and poor with MCS and pain) and acceptable discrimination for three subscales and two single items (AUC: 0.65–0.79). In conclusion, the German-MAP appears to be a reliable and valid questionnaire to assess ADL-limitations in patients with IM. Further research is required, both to substantiate these results and to evaluate responsiveness.

肌炎活动概况量表（Myositis Activity Profile, MAP）是目前唯一一款用于评估炎性肌病（inflammatory myopathy, IM）患者日常生活活动（activities of daily living, ADL）受限情况的疾病特异性问卷。鉴于当前尚无德语版量表，本研究旨在对MAP进行译制，并评估新版德语量表的信度与结构效度。为此，研究团队遵循国际指南开展了跨文化调适工作，共纳入48名IM患者，于两周内两次完成德语版MAP测评；同时采用健康评估问卷（Health Assessment Questionnaire, HAQ）、36条目简明健康量表（36-Item Short Form Survey, SF36）、徒手肌力测试（Manual Muscle Test, MMT8）、定量肌力测试（Quantitative Muscle Testing, QMT）以及功能指数（Functional Index, FI-2）对受试者进行评估。为检验区分效度，另纳入48名年龄与性别匹配的健康对照者完成德语版MAP测评。本研究采用加权卡帕系数（weighted kappa, Kw）评估量表信度，通过斯皮尔曼相关性分析（Spearman correlation analysis）考察MAP与HAQ、SF36躯体组分（physical component measure, PCM）及心理组分（mental component score, MCS）得分、MMT8与QMT肌力测试结果的相关性，区分效度则通过计算曲线下面积（Area under the Curve, AUC）进行评估。结果显示，德语版MAP的4个亚量表具有较好信度（Kw值：0.65~0.71），单个条目亦表现出中等至良好的信度（Kw值：0.57~0.77）；该量表具备良好的结构效度，与HAQ及PCM呈较高相关性，与FI-2、QMT及MMT8呈中等相关性，而与MCS及疼痛指标相关性较弱，同时3个亚量表与2个单个条目具有可接受的区分能力（AUC值：0.65~0.79）。综上，德语版MAP是一款可靠且有效的IM患者ADL受限评估问卷，未来仍需开展进一步研究以验证本研究结果并评估其反应性。