Objectives: To determine the reliability of foot caliper.
Design: Descriptive study.
Setting : Rehabilitation Medicine Out patient Department, King Chulalongkorn Memorial Hospital.
Subject: Fifteen volunteers were recruited from Rehabilitation residents and health care professionals of Department of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital.
Material and Method: The authors created 3 sets of simple Foot Caliper and measured foot dimension including foot width, foot length and toe depth while subjects stood with equal weight bearing to both feet. The authors set 3 examiners to measure foot dimension by the same method.To determine reliability of 3 sets of foot caliper, one examiner was assigned to measure foot dimension of 30 feet with all calipers. To determine the reliability of examiners, all examiners measured foot dimension of the same 30 feet. All parameters were recorded in millimeters.The data was analyzed and presented as intraclass correlation coefficients (ICC) with 95%CI.
Results: There were fifteen volunteers(8 men and 7 women).The average age was 28.6 ± 4.11years(range22 - 39). Average foot width,length and great toe depth (millimeters)were 9.64 ±0.63,24.17 ±1.10 and 1.91±0.24 respectively. For reliability analysis of 3 sets of foot caliper, the intraclass correlation coefficients (ICC) with 95%CI were 0.985(0.972 0.992), 0.996(0.992-0.998) and 0.982(0.968-991) for foot width, length and great toe depth, respectively. For Inter-examiner reliability , intraclass correlation coefficients (ICC) were 0.941(0.864-0.969),0.850(0.746-0.920)and 0.834(0.721-0.910) for foot width, length and great toe depth, respectively. These results showed high agreement of data.
Conclusion: These simple foot calipers have high reliability for foot measurement.These devices are appropriate for clinical use.

Keywords: Foot dimension, Diabetic foot, Foot caliper