Towards Objective Hand Size Assessment and a Standardized Measurement Technique

Abstract

Measurement of anthropomorphic parameters has a reach history, yet only a few standard methods prevailed. Hand size assessment is a particularly understudied area. Proper hand hygiene is essential in healthcare, since the volume of the handrub to be applied depends on the surface area, straightly correlated with hand size. The aim of this study was to interpret a quick, automatized method to describe human hand size, and to validate that by directly comparing to other methods. Six different methods were used to measure the size of the same hands; two paper & pencil-based (Method #1 and #2), two photo-based (Method #3 and #4), one involving an analogue scanner (Method #5) and one fully automated method, using a hand hygiene control device (Method #6). Further, an artificial hand phantom was created, and was measured with Method #2, #4, #5 and #6. The artificial hand was also laser scanned in 3D, and its surface area was precisely determined. 31 adult participants were involved on a voluntary basis. Average hand sizes measured by the 6 different methods were found to be $158.6\pm 16.3, 160.8\pm 17.2, 177.4\pm 24.8, 180.0\pm 29.2, 142.1\pm 13.1, 142.8\pm 16.6$ cm2, respectively. Photo-based methods overestimated the size of the hands compared to paper-based methods; while scanner-based method underestimated it. The surface of the artificial hand was 409.7 cm2, measuring the same hand with Method #2, #4, #5 and #6 resulted 326.7 cm2, 407.9 cm2, 294.8 cm2 and 301.2 cm2, respectively. Based on that results, correction factors were suggested for each method. Results proved that the measurement method applied has a considerable impact on the numeric outcome of hand size measurement. Results of our study were compared to hand size measurements found in the literature. The suggested correction factors can help to compare hand size data determined by different methods. The experimented automated AI-driven software-based method is suitable for routine use.