All-age relationship between arm span and height in different ethnic groups.

Area of Science:

• Anthropometry
• Pulmonary Medicine
• Biostatistics

Background:

• Accurate height measurement is crucial for pulmonary function testing (spirometry).
• Estimating stature from arm span offers a viable alternative when direct measurement is challenging.
• Existing prediction equations may lack multiethnic and all-age applicability.

Purpose of the Study:

• To develop multiethnic, all-age prediction equations for estimating stature from arm span in males and females.
• To assess the clinical utility of these equations in predicting spirometry values (FEV1, FVC).

Main Methods:

• Utilized arm span/height ratio (ASHR) data from 13,947 subjects aged 5-99 years across nine global centers.
• Employed the lambda, mu, and sigma method to model ASHR as a function of age, sex, and geographic group.
• Calculated Z-scores for FEV1, FVC, and FEV1/FVC in 1,503 patients using both measured and predicted heights.

Main Results:

• ASHR demonstrated nonlinear variation with age, was higher in males, and varied significantly across the nine study sites, clustering into four main groups (Asia, Europe, Ghana, Iran).
• Predicted spirometry values (FEV1, FVC, FEV1/FVC) using measured versus predicted height showed minimal differences (SDs: 4.6%, 5.0%, 0.3%).
• Discrepancies in identifying abnormal spirometry patterns (low FEV1, FVC, FEV1/FVC, restrictive pattern) were low (4.2%, 3.2%, 0.4%, 1.0% respectively).

Conclusions:

• Developed group- and sex-specific equations for estimating height from arm span and age.
• These equations are clinically useful for deriving predicted spirometry values, especially when direct height measurement is not feasible.
• The findings support the use of arm span-derived height for accurate pulmonary function assessment across diverse populations.