Clinical methods of goniometry: a comparative study.

This investigation compared the reliability and interchangeable use of three currently available goniometers--a universal goniometer, a fluid goniometer, and an electrogoniometer. Three consecutive readings of the active range of movement of the right elbow joint were taken from each of 23 healthy female volunteers; three experienced observers each used each type of goniometer on two occasions. A balanced experimental design was used to eliminate order effects with respect to subject, tester, or goniometer, and a rigid protocol was employed to reduce error due to diurnal or methodological variations. The results show that there are significant differences between the goniometers used, the testers, and the replications. Significant interaction effects also exist between the goniometers and the occasion, the goniometers and the testers, and the testers and replications. The data suggest that the interchangeable use of different types of goniometer in a clinical setting is inadvisable.