Reliability of the Arch Height Index as a Measure of Foot Structure in Children

To determine the intrarater and interrater reliability of the arch height index (AHI) in children developing typically. The AHI is tested with a device that measures foot structure. Thirty children, ages 6 to 12 years, participated for a total of n = 60 feet. The AHI measurements were taken by 2 investigators in sitting and standing and repeated twice by each investigator in a single visit. Intrarater and interrater reliabilities were determined using intraclass correlation coefficient (ICC) (2,1) statistical analysis. The mean age was 9.61 ± 1.96 years. The intrarater and interrater reliability had an ICC 0.76 or more in both sitting and standing. The average AHI value was 0.36 ± 0.02 in sitting and 0.32 ± 0.02 in standing. Pediatric therapists, physicians, and orthotists should consider using the AHI as an objective measure to be used for research, to assess foot structure, monitor change over time, and assist with treatment planning in children.