Concurrent validity and intertester reliability of universal and fluid-based goniometers for active elbow range of motion

Area of Science:

• Biomechanics
• Physical Therapy
• Measurement Science

Background:

• Accurate measurement of joint range of motion (ROM) is crucial in physical therapy and rehabilitation.
• Standard goniometers are widely used but can exhibit variability in measurements.
• Novel instruments like fluid-based goniometers aim to improve measurement accuracy and reliability.

Purpose of the Study:

• To establish the concurrent validity of the universal goniometer and the fluid-based goniometer.
• To determine the intertester reliability of both goniometers for elbow ROM measurement.

Main Methods:

• A correlational study involving 30 healthy subjects was conducted.
• Two testers measured elbow range of motion using both universal and fluid-based goniometers.
• Statistical analyses included Pearson product-moment correlation and t-tests.

Main Results:

• The fluid-based goniometer exhibited high intertester reliability (R = .92).
• The standard universal goniometer showed poor intertester reliability (R = .53).
• A significant difference was found between the two instruments (t = 4.4, p < .05), with a correlation of R = .83.

Conclusions:

• The fluid-based goniometer is reliable for intertester measurements of elbow ROM.
• The universal goniometer's reliability is questionable for consistent intertester measurements.
• The fluid-based goniometer and universal goniometer are not interchangeable for elbow ROM assessment.