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Ideal body weight (pediatric)

Standing height (or recumbent length in infants). Accepts cm, inches, or metres. The Traub methods are validated 1–17 years; the Devine method appears only at or above 152.4 cm (60 inches).

Used only by the Devine method (male base 50.0 kg, female 45.5 kg). The Traub–Kichen and simplified Traub equations are sex-independent by design, so sex does not change those values.

Independent clinical validation: pending

Two independent clinical validators will be named here once review is complete.

Validator slot open 1
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How it is calculated

Ideal body weight (kg) is estimated from height, shown per method. Traub–Kichen (exponential): IBW = 2.396 × e^(0.01863 × height in cm) — sex-independent, validated 1–17 years. Simplified Traub (Lexicomp quadratic): IBW = (height in cm)² × 1.65 ÷ 1000 — same domain, runs about 7% higher than Traub–Kichen (16.50 vs 15.44 kg at 100 cm). Devine (adult-derived, shown only when height is at or above 60 inches / 152.4 cm): height in inches = height in cm ÷ 2.54, then IBW = 50.0 + 2.3 × (height in inches − 60) for males and 45.5 + 2.3 × (height in inches − 60) for females. Pick the method appropriate to the child's age and height (see notes). Values are raw; the display rounds to 0.1 kg.

Limitations and notes

No consensus method exists — the published methods disagree, most in adolescents and at extreme percentiles (≥10 kg in Ward 2018, PMID 30277896; 13.7–16.6% median disagreement in Moylan 2019), so each height-computable method is shown separately and none is silently chosen. IBW has NO interpretive bands: it is an input to weight-based drug dosing, to %-IBW nutritional classification (%IBW = actual weight ÷ IBW × 100; the McLaren & Read 1972 malnutrition categories attach to that derived ratio, NOT to IBW), and to lung-protective tidal-volume setting in pediatric ARDS — interpretation is intentionally empty. Method applicability by age/height: Traub–Kichen (A1) is the primary pediatric height-based equation, validated ages 1–17 y and sex-independent by design; the simplified Traub quadratic (A2) is a Lexicomp approximation over the same domain and is NOT numerically equal to A1 (~7% higher). Devine (A3) is ADULT-DERIVED (a 1974 gentamicin-dosing formula), requires sex, and is only defined for height > 60 in (152.4 cm), so it is emitted only at/above 152.4 cm and over-estimates versus pediatric methods (~65.9 vs 56.9 kg at 170 cm). Units caveat: the simplified Traub formula takes CENTIMETRES — Moylan 2019 prints it with 'inches', an apparent transcription error that yields non-physiologic values; centimetres reproduces the Traub curve. Below ~1–2 years, height-only equations are weakest (Traub validated from 1 y; Devine invalid), and the reference-standard growth-chart methods (McLaren, Moore, ADA, BMI50) require CDC/WHO LMS percentile-table lookups — they are NOT computable from height alone and are therefore documented but NOT implemented here (BMI-for-age is undefined < 2 y). [NEEDS SOURCE] carried from the research file: Traub & Johnson 1980 PMID (not fetched); McLaren & Read 1972 PMID (not confirmed); Moore 1985 exact volume/pages; ADA 2003 exact page; the BMI50 original primary citation; and the Moylan 2019 exact journal/venue. Training aid, not a prescription — confirm any weight-based dose against a current pediatric reference.

Accepted input ranges

  • Height / recumbent length — 45–200 cm
  • Sex

References

  1. Traub SL, Kichen L. Estimating ideal body mass in children. Am J Hosp Pharm. 1983;40(1):107–110.PMID 6823980
  2. Kang K, Absher R, Farrington E, Ackley R, So T-Y. Evaluation of Different Methods Used to Calculate Ideal Body Weight in the Pediatric Population. J Pediatr Pharmacol Ther. 2019;24(5):421–430.PMID 31598106DOI 10.5863/1551-6776-24.5.421
  3. Ward SL, Quinn CM, Steurer MA, Liu KD, Flori HR, Matthay MA. Variability in Pediatric Ideal Body Weight Calculation: Implications for Lung-Protective Mechanical Ventilation Strategies in Pediatric ARDS. Pediatr Crit Care Med. 2018;19(12):e643–e652.PMID 30277896DOI 10.1097/PCC.0000000000001740
  4. Moylan A, et al. Assessing the Agreement of 5 Ideal Body Weight Calculations for Selecting Medication Dosages for Children With Obesity. 2019.Source
  5. physiology R package — ideal_weight_Traub.Source

Version and changelog

v1.0.0 · General

  • 2026-07-25 v1.0.0 — Initial release: pediatric IBW via Traub–Kichen, simplified Traub, and (height > 152.4 cm) Devine.

Important

For use by qualified health professionals as an informational and educational aid. It supports clinical judgment and does not replace it. Verify every result independently before making a clinical decision. This is not a medical device.