A study to compare the reliability of composite finger flexion with goniometry for measurement of range of motion in the hand.

OBJECTIVE: To establish the intra- and inter-rater reliability of composite finger flexion (CFF), and to compare this with goniometry.
DESIGN: Fifty-one physiotherapists and occupational therapists took part in the study. The hand of a normal subject was splinted in three different positions. Using a goniometer and a ruler alternately, each therapist measured both the proximal interphalangeal joint and CFF of three digits, following a standardized protocol. This process was repeated three times.
SETTING: Eighteen NHS hospital sites in the UK.
RESULTS: The two measurement methods produced different ranges and standard deviations for each digit. The repeatability coefficient shows that repeated intra-rater goniometric measures fall within 4-5 degrees of each other 95% of the time. Inter-rater goniometric measures fall within 7-9 degrees. Repeated intra-rater CFF measures fall within 5-6 mm of each other, whereas inter-rater fall within 7-9 mm. The influence of occupation, experience in hand therapy, years of practice and routine use were found to have no effect on reliability. Scaling of the two methods of measurement allowed comparison between them to be made. CFF and goniometry are equally reliable when comparing inter-rater reliability, but goniometry displays less variability than composite finger flexion for intra-rater measurements.
CONCLUSION: In this study involving a subject with normal joints, goniometry is more reliable than CFF when only one measurer is involved. However, CFF may be a useful alternative where multiple joint measures are required, or when goniometry is impracticable.