The accuracy of arm-associated height estimation methods compared to true height in a multi-racial group of young South African adults.
Background: Stretch stature is the gold standard for measuring true height, but when this is not possible height estimation methods are used. To date, only two South African studies regarding height estimation techniques have been published. Objective: To investigate the accuracy of arm-associated height estimation methods used for the calculation of true height compared to stretch stature in young South African adults. Design: A cross-sectional descriptive design was employed. Setting: Pietermaritzburg, Westville and Durban, KwaZulu-Natal, South Africa, 2015. Subjects: Convenience sample (N=900) aged 18 to 24 years, which included an equal number of subjects from both genders (n=150 per gender) stratified across race (White, Black and Indian). Results: Highly significant differences exist between genders (p<0.001), where males had larger stretch statures and arm-associated measurements than females (p<0.001). Highly significant differences exist between race groups (p<0.001), where whites had significantly different stretch statures as well as different armassociated measurements compared to Blacks and Indians. Some similarities were found between race groups, especially between Blacks and Indians. Arm-associated height estimation methods can be used as estimates of true height in accordance with the following study findings: (i) among Black African males, the World Health Organisation (WHO)-adjusted equation would seem to be the most appropriate, followed by demi-span male equation; (ii) among Black African females, the demispan female equation would seem to be the most appropriate, followed by total armspan; (iii) among Caucasian males, the total armspan would seem to be the most appropriate, followed by half-armspanx2; (iv) among Caucasian females, the total armspan would seem to be the most appropriate, followed by half-armspanx2; (v) among Indian males, the demi-span male equation would seem to be the most appropriate, followed by the WHO-adjusted equation; and (vi) among Indian females, the WHO-adjusted equation would seem to be the most appropriate, followed by demi-span female equation. Discussion:. The anthropometric variation between genders and race groups was linked to the exposure to secular growth conditions, which influences a subject's physiological ability to achieve their maximal height. The Vitruvius theory was proposed where total armspan potentially represents a subject's maximal height, and the ability for them to reach that height is dependent on exposure to consistent ambient secular growth conditions during the window period and beyond. Conclusion: In conclusion, this study's findings provides a baseline for future height studies to be conducted on the South African population, where each anthropometric method should be validated for each race and gender.