The original OMERACT Filter to determine applicability of a measurement instrument in a setting2. From Boers, et al. J Rheumatol 1998;25:198–9. Adapted with permission.
| Truth | Is the measure truthful, does it measure what is intended? Is the result unbiased and relevant? The word captures issues of face, content, construct and criterion validity. As gold standards are usually not available, criterion validity is mostly not tested |
| Discrimination | Does the measure discriminate between situations of interest? The situations can be states at one time (for classification or prognosis) or states at different times (to measure change). The word captures issues of reliability and sensitivity to change |
| Feasibility | Can the measure be applied easily, given constraints of time, money, and interpretability? The word captures an essential element in the selection of measures, one that may be decisive in determining a measure’s success |