Phenice-Style Dichotomy
Definition
A simplification used in some research that collapses ASUDAS continuous scores into present/absent dichotomies for frequency comparison. Useful for older literature but loses grade information; full ASUDAS scoring is preferred in modern forensic work.
- Basis
- Collapses ASUDAS grade scores into present/absent
- Named after
- Analogy to Phenice's simple trait-scoring approach
- Trade-off
- Loses ordinal grade information
- Typical use
- Comparing older dental non-metric literature
Common questions
Why would a researcher deliberately throw away grade information?+
Many older published datasets only recorded presence or absence of a trait, so dichotomizing a newer full ASUDAS scale is the only way to compare new data against that older literature on equal terms.
What is lost when a graded trait is reduced to a yes or no?+
Subtle population differences that show up as shifts in trait expression intensity, such as shovel-shaped incisors ranging from trace to pronounced, disappear once every non-zero grade is collapsed into a single 'present' category.
Is this dichotomy still acceptable in current forensic ancestry casework?+
Full ASUDAS grade scoring is preferred for modern estimates because it preserves more discriminating information; the dichotomy is mainly a tool for reconciling data with legacy studies, not a first-choice scoring method.
Related terms
- ASUDAS
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