Reliability, validity, and clinical usability of a digital goniometer

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Clinical Measurement

Background:

• Accurate joint range of motion (ROM) measurement is crucial for physical therapy assessment and treatment.
• Traditional universal goniometers (UG) are widely used but can be subject to user variability.
• Advancements in digital measurement tools offer potential for improved accuracy and reliability.

Purpose of the Study:

• To validate a novel digital goniometer (DG) prototype for joint ROM assessment.
• To compare the inter- and intra-rater reliability of the DG against the established UG.
• To evaluate the clinical usability and potential adoption of the DG by physical therapists.

Main Methods:

• The study involved 18 healthy models and 5 physical therapists.
• Reliability was assessed using repeated measures of 5 joint motions by 5 therapists on 6 models across 3 sessions for both UG and DG.
• Validity was determined by comparing DG measurements to 8 computer-aided design (CAD) angles.
• Clinical usability was assessed via pre-/post-surveys for physical therapist participants.

Main Results:

• No statistically significant differences were found between the digital goniometer (DG) and universal goniometer (UG).
• The DG demonstrated equivalent inter- and intra-rater reliability compared to the UG.
• The DG yielded higher inter-rater Intraclass Correlation Coefficient (ICC) values for all 5 measured joint motions.

Conclusions:

• The digital goniometer (DG) possesses adequate concurrent criterion-related validity for joint ROM assessment.
• The DG offers reliability comparable to the universal goniometer (UG).
• Survey results suggest novel features of the DG may increase its likelihood of adoption by clinicians.