Stewart 1979 Cut-Offs
Definition
The original US femoral head diameter sex classification thresholds derived by T.D. Stewart from a US military and dissection-room sample. Widely cited but not applicable to Indian or South-East Asian populations without downward adjustment of approximately 2-4 mm.
- Author
- T.D. Stewart
- Year
- 1979
- Basis
- Femoral head diameter, US military and dissection-room sample
- Population caveat
- Needs downward adjustment of about 2-4 mm for Indian or South-East Asian populations
Common questions
Why can't the Stewart cut-offs be applied directly to an Indian skeletal case?+
The thresholds were derived from a US reference sample whose average femoral head diameter is larger than in Indian and South-East Asian populations, so applying the same cut-off without downward adjustment risks misclassifying smaller male femora as female.
What is the practical fix examiners use instead of Stewart's raw thresholds?+
Examiners either apply a population-specific correction of roughly 2 to 4 mm downward or use sectioning points derived from a local reference sample where one exists, rather than treating the original US thresholds as universal.
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