There is an agreement among the various professional and governmental entities concerned with performance testing that selection of a test must be undertaken within the hierarchical context of five standards:

• Safety: is a function of the match between the performance demands placed on the patient and the patient’s ability to limit performance appropriately.
• Reliability: The test equipment and test protocol should produce a result that is stable within the test trial, and across evaluators, patients, and the date of the test administration.
• Intra-test reliability: a measure of the patient’s consistency of responding can be assessed through various mathematical means using the coefficient of variation statistic as a measure of the consistency of the patient’s performance on a repeated-trials task.
• Validity: The interpretation of the test score should be able to predict or reflect the patient’s performance in a target task. A valid measure Functional Evaluation must be used with impaired patients must allow the clinician to gauge treatment effect by comparing an initial baseline level of performance with performance at the conclusion of the treatment.
• Utility: The usefulness of the procedure is the degree to which it meets the needs of the patient, doctor, and insurance company.