Non-radiographic validity and reliability measures for assessing foot types: A systematic review

Static measurements of the midfoot region suggested: AHI, FPI, and Staheli Arch Index.▪ •A classification, with standardized measures, to determine foot types is lacking.•Studies present a wide variety of methods for classifying foot types.•Static measures such as AHI, FPI, and SAI present valid and reliable normative value.•These measures can be applied in clinical practice and for future research. Foot type classification is well recognized in clinical practice and orthopedic literature, a universally accepted classification or standardized measures to determine foot types are lacking. The objective of this study was to identify which non-radiographic assessment methods are considered valid and/or reliable for the classification of foot types. A systematic database search was performed. Only cross-sectional studies that performed reliability and/or validity analysis of non-radiographic methods were included. To evaluate the risk of bias, the Critical Appraisal Tool (CAT) was used to evaluate the measurement properties of objective clinical methods. Twenty-six studies were included. The results of reliability and validity, in general, demonstrated high scores, but, inconsistencies were related to the variability of the measurements, heterogeneity of the methods used to determine reliability and validity, and lack of parameters for classifying foot types, which resulted in few elements to determine which method of foot type evaluation is valid and reliable. Given the Intraclass Correlation Coefficient and CAT results and the presence of normative values, the static measurements of the “Arch Height Index”, “Foot Posture Index”, and “Staheli Arch Index” can be suggested to classify foot types.