Table 3 Results of measurement properties related to: reliability
From: Evaluation of the measurement properties of the Manchester foot pain and disability index
Measurement property | Research question | Method | Dataset(s) | Results | Interpretation |
|---|---|---|---|---|---|
Internal consistency | Do the items within the (uni-dimensional) sub-scales correlate highly? | Cronbach’s α (per sub-scale) | NL T0 | Function: 0.84 | The foot function scale is internally consistent (>0.7). Internal consistency of the other sub-scales is moderate. |
n = 205 | Pain: 0.67 | ||||
Perception: 0.61 | |||||
Test-retest reliability | Does the Dutch MFPDI produce similar results when completed repeatedly within an interval of two weeks? | ICC absolute agreement (per sub-scale) | NL Ts and NL T0 | Function: 0.69 | The test-retest reliability of the function scale is nearly acceptable. Neither of the other scales is reliable. |
n = 195 | Pain: 0.49 | ||||
Perception: 0.10 | |||||
Measurement error (agreement) | Which part of the variance is due to measurement error? | SEM (per sub-scale) | NL Ts and NL T0 | Function: 2.2 | There are no set guidelines of what is acceptable for the magnitude of SEM. Function scale SEM of total score is: 12%, pain scale: 16%, perception: 36% |
n = 195 | Pain: 1.6 | ||||
Perception: 2.1 |