Reliability of Q-Angle Measurement
Date of Award
Master of Science (MS)
Community & Environmental Health
Community Health Education
Gregory M. Frazer
John L. Echternach
Call Number for Print
Special Collections LD4331.C48G78
Various methods of measuring the Q-angle are reported in the literature. The reliability of these measurement methods has not been established. The purpose of this study was to examine the intra- and inter-tester reliability of a method for measuring the Q-angle using a goniometer. The measurement method was performed on 40 normal, healthy subjects who volunteered to participate in the study. There were 27 female subjects and 13 male subjects.
Two physical therapists (Tester 1 and Tester 2) took repeated Q-angle measurements. Measurements were taken on the same day with an interval of five to 10 minutes between measurements. Measurements were also taken with a one to two week time lapse between trials. The testers measured the Q-angles using blinded goniometers. Assistants read and recorded the measurements.
Intra-class correlation coefficients (ICCs) were used to determine the degree of agreement between repeated measurements taken by the same tester and between measurements taken by the two testers. The ICC values for intratester reliability of Tester 1 were .87 for measurements taken five to 10 minutes apart and .56 for measurements taken one to two weeks apart. The ICC values for intra-tester reliability of Tester 2 were .81 for measurements taken five to 10 minutes apart and . 76 for measurements taken one week apart. Results of the ICC for inter-tester reliability was .11.
The ICC for measurements, taken five to 10 minutes apart, indicate good intra-tester reliability for both Tester 1 and Tester 2. Results of the ICC for repeated measurements taken one to two weeks apart indicate fair to poor intratester reliability. Results of the ICC between the two testers indicate very poor inter-tester reliability. Further studies on the Q-angle are recommended.
In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
Grusheski, Elisabeth A..
"Reliability of Q-Angle Measurement"
(1989). Master of Science (MS), Thesis, Community & Environmental Health, Old Dominion University, DOI: 10.25777/pb24-b376