Table 3 Overview of all measurement properties, including their definitions
Measurement property | Definition according to the COSMINa taxonomy | Percentage of agreement in the Delphi study (%) |
|---|---|---|
Content validity (including face validity) | The degree to which the content of a measurement instrument is an adequate reflection of the construct to be measured | 93 |
Reliability | The degree to which the measurement is free from measurement error | 91 |
Responsiveness | The ability of a measurement instrument to detect change over time in the construct to be measured | 91 |
Internal consistency | The degree of interrelatedness among the items | 90 |
Structural validity | The degree to which the scores of a measurement instrument are an adequate reflection of the dimensionality of the construct to be measured | 83 |
Measurement error | The systematic and random error of a patient’s score that is not attributed to true changes in the construct to be measured | 83 |
Hypotheses testing | The degree to which the scores of a measurement instrument are consistent with hypotheses based on the assumption that the measurement instrument validly measures the construct to be measured | 82 |
Criterion validity | The degree to which the scores of a measurement instrument are an adequate reflection of a “gold standard” | 76 |
Cross-cultural validity | The degree to which the performance of the items on a translated or culturally adapted measurement instrument is an adequate reflection of the performance of the items of the original version of the measurement instrument | 70 |