A sizing improvement methodology based on adjustment of interior accommodation rates across measurement categories within a size chart

The purpose of this paper is to identify common issues among commercial body size charts, and to propose a sizing improvement methodology without changing the number of sizes in the range. One goal is to equalize the number of people accommodated by each size within the range, and to propose a way to evaluate the effectiveness of the improvement.

The proposed method consists of three phases: (Phase I) identify target population; (Phase II) analysis of existing size charts; and (Phase III) improvement of the initial size chart. Phase III is the key process, which includes repeated manipulation of intersize intervals of the three primary measurements (chest, waist and hip) for improved consistency of overall and interior accommodate rates among the three measurement categories. A program was developed in RStudio® to generate trials and side-by-side bar plots for visualization of the differences in accommodate rates.

The main issue in commercial body size charts observed is the inconsistency of the interior accommodation rates among measurement categories. Some other issues include: lack of important measurements, failure to provide ranges and gaps between measurement ranges of adjacent sizes.

This paper proposed a complete work flow to improve body size charts to fix the common issues. The method integrates historic size information and new anthropometric information extracted from a national-scale sizing database (e.g. SizeUSA). The study also brought association of the secondary body measurements with primary measurements without using linear regression. Hence, information from body size charts can be more efficiently used in acquiring other size information.