Height measurement is unreliable when neuromuscular weakness or spinal deformity is present. The aim of this study was to accurately predict pulmonary function from a limb segment (ulna) measurement that is precise and reproducible. Equations are available in caucasian children but are not available in children of sub-saharian or caribbean ethnicity, which was the aim of the study. To this end, 350 black children referred for pulmonary function testing for asthma follow-up will be included.

Ulna (dominant and non-dominant arm), height measurement in 350 asthmatic children of sub-saharian or caribbean ethnicity (both parents). Repeatability analysis (ulna and height) for the first fifty children. Recording of pulmonary function tests results (spirometry, resistance measurements)

Inclusion Criteria:

• age: 3 to 18 years old, two parents of sub-saharian or caribbean origin, referred for asthma suspicion or follow-up.

Exclusion Criteria:

• chronic disease excepting asthma, prematurity (<36 GW), steroid (>3/year), high dosage of inhaled steroid

child between 3 to 18 years old, two parents of sub-saharian or caribbean origin, referred for asthma suspicion or follow-up