Brazilian Journal of Physical Therapy
On-line version ISSN 1809-9246
GADOTTI, IC; VIEIRA, ER and MAGEE, DJ. Importance and clarification of measurement properties in rehabilitation. Rev. bras. fisioter. [online]. 2006, vol.10, n.2, pp. 137-146. ISSN 1809-9246. http://dx.doi.org/10.1590/S1413-35552006000200002.
OBJECTIVE: The purpose of this paper was to critically review the concepts and types of measurement reliability, validity, and responsiveness, and to discuss their implications for rehabilitation research and high-quality clinical practice. METHOD: A critical literature review considering the strengths, limitations, and appropriate applications of measurement properties in rehabilitation was conducted. RESULTS AND DISCUSSION: Measurement quality is assessed using criteria such as reliability, validity, and responsiveness. Many published studies do not report these measurement properties, which are related, sometimes overlapping, and are frequently confused. This review paper clarifies the meanings of the concepts and types of reliability, validity, and responsiveness. It gives examples that are relevant for the field of rehabilitation. It discusses how the measurement properties interact with each other and influence the size of the effect and the power of studies. CONCLUSION: Measurements are essential in rehabilitation research and clinical evaluation. Measurement properties should be reported to allow readers to evaluate the quality of the results presented. The clarification of measurement properties provided in this paper may contribute towards standardizing definitions and improving the quality of rehabilitation research and clinical practice.
Keywords : measurements; reliability; validity; responsiveness; study power.