The World Health Organization (WHO) has published data on the physical development of infants and children up to 5 years of age.

Patient selection: infant or child up to 5 years of age (up to 1,856 days of age)



(1) birthdare

(2) date of examination

(3) gender

(4) arm circumference in cm


age in days =

= ((date of exam) - (birthdate))


z-score =

= ((weight) - (mean)) / (standard deviation)


The difference between Z-scores for a given age are unequal so table look-up used.

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