An agreement on foot posture classification between screening tests using arch height measure and footprint index

Abstract

At present a variety of screening test categorizing foot posture has been developed. Common clinical tests are arch height measure and footprint index. If the tests demonstrate the good agreement, it could be applied to replace each other for categorizing foot posture. Therefore, the present study aimed to determine the level of agreement between the arch height measure using a normalized navicular height truncated (NNHt) and the footprint index using a Chippaux-Smirak Index (CS-I). The present study was conducted in 102 participants (37 males and 65 females) aged between 18-40 years with normal body mass index and no musculoskeletal disorder in ankle and foot. Right foot of the participants was measured by the NNHt and CS-I on the same day with a 10-min rest between the tests. Agreement analysis between the tests was determined by the Weighted Kappa (K_w). Using the NNHt, 55.88% of participants had a neutral foot, 41% had a pronated foot and 3.92% had a supinated foot. Using the CS-I, 79.41% of participants had a neutral foot, 11.77% had a pronated foot and 8.82% had a supinated foot. The agreement between the tests was slight (K_w = 0.123). Therefore, the NNHt and CS-I cannot be substituted for each other in classifying foot posture.