The reliability of an assessment is the extent to which the measurement will consistently provide similar results over time. Validity is the extent to which the tool actually measures what it says it measures. A functional capacity assessment with a high degree of reliability and validity will accurately represent the worker's capacities to perform job functions. It is unnecessary to repeat the assessment over two days when the statistical reliability is high. These functional results can be heavily relied upon to establish treatment plans and return to work activities.
Procedural standardization is another critical component of clinical measurement.
Assessors are required to measure the same areas at the same point throughout assessment, using standardized equipment and procedures. The data can then be collected in an objective and consistent fashion. Collecting data in a consistent methodology ensures the accuracy of the assessment. The use of computerized assessments helps to cut down on the time required for data analysis, thus minimizing any delays in reporting. Once the information is stored electronically, access can be obtained for comparisons in the extensive database.