Pediatric Kaup and Rohrer Indices
Kaup is shown at 3–71 completed months, and Rohrer at 72–155 completed months. This does not diagnose growth status, obesity or underweight.
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For example, 4 years 0 months = 48
Kaup index
3–71 monthskg/m² (same calculation as BMI)
Rohrer index
72–155 monthsConventional height-cubed index
Enter all three measurements to calculate.
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Equations, age bands and limitations
Equations
Kaup = weight (kg) / height (m)²; it is numerically BMI but adult BMI diagnostic classes are not applicable. Rohrer = 10 × weight (kg) / height (m)³.
Hypothetical examples
24 months, height 80 cm and weight 12.8 kg: Kaup 20.00. At 72 months, 100 cm and 12.5 kg: Rohrer 125.00.
Population and limits
Historical age bands are display conventions, not clinical cutoffs. For under 3 months or 156 months and older, no index is displayed. Interpretation requires pediatric growth charts and clinical context. Input ranges are unit-entry safeguards, not medical eligibility criteria.
Source and review
Sources checked 2026-11-10.