ABSTRACT
Reliability can have different meanings when applied to human performance, equipment and measurement (Crowder et al., 2000: 1). Reliability of equipment and systems is concerned with the probability that the system is working successfully. Typical measures used in the evaluation of this type of reliability are mean time between failure and rate of failure occurrence ( Sommerville, 1992: 394–5). The reliability of a human performer could be the ability of the person to consistently perform specified tasks to a required standard. This chapter is concerned with the reliability of measurement within scientific research. The chapter commences by covering the measurement issues of validity, objectivity and reliability and their inter-relationships. The different types of reliability study done in sport and exercise science are then classified. There are many different reliability statistics that can be used appropriately or inappropriately. Therefore, the chapter includes a section on selecting the appropriate reliability statistic to use in different situations. Finally, the chapter describes how to produce reliability statistics.
