Intraobserver reliability refers to the stability of an individual’s observation of phenomenon at two or more intervals of time, according to sociology professor Russell K. Schutt's book, “Investigating the Social World: The Process and Practice of Research.” Simply stated, it’s the ability to consistently get the same results when making observations at different times. For example, a doctor with good intraobserver reliability skills would read a patient’s X-ray or medical diagnostic test the same way when viewing it several weeks later. Intraobserver reliability is also called self-reliability or intrarater reliability.

Importance of Intraobserver Reliability

The quality of data generated from a study depends on the ability of a researcher to consistently gather accurate information. Training, experience and researcher objectivity bolster intraobserver reliability and efficiency. For instance, animal behaviorist D.K. Scott claims to have trained herself to recognize 450 swans in the wild to lend credibility to her observations of the birds’ social behavior. Researchers often videotape phenomenon and review it multiple times to ensure their facts. Intraobserver reliability leads to findings that can be replicated by other researchers.