Fig 1.
From 76 people with myositis fulfilling all inclusion criteria 50 agreed to participate. After the first measurement four participants dropped out.
Fig 2.
Procedure of the intra- and interrater reliability.
Each patient was measured three times. For intrarater reliability MMT8 and HHD were performed by the same tester (Measurement 1 and 2) and for interrater reliability MMT8 and HHD were performed by two different testers (Measurement 2 and 3). Abbreviations: MMT8: Manual muscle test 8, HHD: Hand-held dynamometry.
Table 1.
Kendall 10-point scale.
Table 2.
Demographic and health related data of the participants (n = 50).
Table 3.
Peak force at M1, M2 and M3 plus intra- and interrater reliability measured with hand-held dynamometry (N = 46).
Table 4.
Averaged peak force at M1, M2 and M3 plus intra- and interrater reliability measured with hand-held dynamometry (N = 46).
Fig 3.
Bland and Altman plots of hand-held dynamometry (peak force).
The blue continuous horizontal line shows the mean difference between tests. The dashed orange horizontal lines show the upper and lower 95% limits of agreement (bias ± 1.96 × standard deviation). Abbreviations: M: measurement, S_ABD: shoulder abduction, E_FLEX: elbow flexion, A_EXT: ankle extension, H_ABD: hip abduction, H_EXT: hip extension, K_EXT: knee extension, W_EXT: wrist extension, N_FLEX: neck flexion.
Fig 4.
Bland and Altman plots of hand-held dynamometry (peak force).
The blue continuous horizontal line shows the mean difference between tests. The dashed orange horizontal lines show the upper and lower 95% limits of agreement (bias ± 1.96 × standard deviation).Abbreviations: M: measurement, S_ABD: shoulder abduction, E_FLEX: elbow flexion, A_EXT: ankle extension, H_ABD: hip abduction, H_EXT: hip extension, K_EXT: knee extension, W_EXT: wrist extension, N_FLEX: neck flexion.
Table 5.
MMT8 single muscle groups at M1, M2, M3 plus intra- and interrater Kappa values (N = 46).
Table 6.
MMT8 total score at M1, M2, M3 plus intra-and interrater reliability (N = 46).
Table 7.
MMT8 graded score at M1, M2, M3 plus intra- and interrater Kappa values (N = 46).
Fig 5.
All but one muscle group (hip extension) showed ceiling effects of 22 to 82%. Abbreviations: A_EXT: ankle extension, E_FLEX: elbow flexion, W_EXT: wrist extension, K_EXT: knee extension, N_FLEX: neck flexion, S_ABD: shoulder abduction, H_ABD: hip abduction, H_EXT: hip extension.
Table 8.
Correlations (Spearman`s rho) between peak force (averaged and normalized) and MMT8 (N = 50).
Fig 6.
Muscle strength measured by hand-held dynamometry (in Newton) and MMT8 (MMT-Scale).
The association between results from MMT8 and HHD are not consistent.
Fig 7.
Measuring knee extension using a belt to stabilize the dynamometer.
Standard body position of the patient and the device are shown with knees and hips flexed to 90°.
Fig 8.
Measuring hip extension using a belt to stabilize the examiner.
Standard body position of the patient and the device are shown with stretched hip and knees.