ORIGINAL ARTICLES Dynamic Footprint Measurement Collection Technique and Intrarater Reliability Ink Mat, Paper Pedography, and Electronic Pedography Jeanna M. Fascione, DPM*† Ryan T. Crews, MS* James S. Wrobel, DPM, MS* Background: Identifying the variability of footprint measurement collection techniques and the reliability of footprint measurements would assist with appropriate clinical foot posture appraisal. We sought to identify relationships between these measures in a healthy population. Methods: On 30 healthy participants, midgait dynamic footprint measurements were collected using an ink mat, paper pedography, and electronic pedography. The footprints were then digitized, and the following footprint indices were calculated with photo digital planimetry software: footprint index, arch index, truncated arch index, Chippaux-Smirak Index, and Staheli Index. Differences between techniques were identified with repeated- measures analysis of variance with post hoc test of Scheffe. In addition, to assess practical similarities between the different methods, intraclass correlation coefficients (ICCs) were calculated. To assess intrarater reliability, footprint indices were calculated twice on 10 randomly selected ink mat footprint measurements, and the ICC was calculated. Results: Dynamic footprint measurements collected with an ink mat significantly differed from those collected with paper pedography (ICC, 0.85–0.96) and electronic pedography (ICC, 0.29–0.79), regardless of the practical similarities noted with ICC values (P ¼ .00). Intrarater reliability for dynamic ink mat footprint measurements was high for the footprint index, arch index, truncated arch index, Chippaux-Smirak Index, and Staheli Index (ICC, 0.74–0.99). Conclusions: Footprint measurements collected with various techniques demonstrate differences. Interchangeable use of exact values without adjustment is not advised. Intrarater reliability of a single method (ink mat) was found to be high. (J Am Podiatr Med Assoc 102(2): 130-138, 2012) Work to improve the clinical appraisal of foot function is ongoing. Several techniques exist, includ- ing footprints, radiographs, direct anatomical mea- surements, and various dynamic laboratory analyses. Many studies 1-18 have specifically assessed footprint measurements and their ability to predict foot structure and abnormalities. Common footprint measurements include contact area (CA), footprint index (FPI), arch index (AI), truncated AI (TAI), Chippaux-Smirak Index (CSI), and Staheli Index (SI). Far more research has focused on the collection of footprints under static conditions rather than dynamic conditions. One particular study 19 con- cluded that the accuracy of CA measurements collected with pressure platforms and traditional ink prints produced large error (.10%). Therefore, that same study 19 suggested assessing each device according to a weighted method and spatial resolution error. Another study 20 demonstrated that the pressure platform, compared with the ink technique, significantly underestimates the static CA, resulting in an AI change. More specifically, *Scholl College of Podiatric Medicine at Rosalind Franklin University of Medicine and Science, Center for Lower Extremity Ambulatory Research, North Chicago, IL. †Podiatric Medicine & Surgery Residency Program, Advo- cate Illinois Masonic Medical Center, Chicago, IL. Corresponding author: Jeanna M. Fascione, DPM, Scholl College of Podiatric Medicine at Rosalind Franklin Univer- sity of Medicine and Science, Center for Lower Extremity Ambulatory Research, 3333 Green Bay Rd, North Chicago, IL 60305. (E-mail: jeanna.fascione@gmail.com) 130 March/April 2012  Vol 102  No 2  Journal of the American Podiatric Medical Association