Body hair counts during hair length reduction procedures: a comparative study between Computer Assisted Image Analysis after Manual Processing (CAIAMP) and Trichoscan(™)

Abstract

Purpose: To compare two measurement methods for body hair.

Methods: Calibration of computer assisted image analysis after manual processing (CAIAMP) showed variation <4% for thickness and <2.3% for densities. Images from 6 body sites with 'good natural contrast between hair and skin' were taken before hair dye, after hair dye or after hair length reduction without hair extraction or destruction. Data in the same targets were compared with Trichoscan(™) quoted for 'unambiguous evaluation of the hair growth after shaving'.

Results: CAIAMP detected a total of 337 hair and showed no statistically significant differences with the three procedures confirming 'good natural contrast between hair and skin' and that reduction methods did not affect hair counts. While CAIAMP found a mean number of 19 thick hair (≥30 μm) before dye, 18 after dye and 20 after hair reduction, Trichoscan(™) found in the same sites respectively 44, 73 and 61. Trichoscan(™) generated counts differed statistically significantly from CAIAMP-data. Automated analyses were considered un-specifically influenced by hair medulla and natural or artificial skin background.

Conclusion: Quality control including all steps of human intervention and measurement technology are mandatory for body hair measurements during experimental or clinical trials on body hair grooming, shaving or removal.

Keywords: body hair; computerized method; hair removal; shaving.