Boundary Comparison Lab · F99

Compare any two F99 categories

Pick two categories and see what actually discriminates them: overlap, decisive evidence, duration/course, exclusions, and the common trap. This is a separate learning mode from the Differential Decision Lab — here you are studying a boundary directly, not making a single timed decision.

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• F99 vs F09

  Distinguish chapter-level residual uncertainty (F99 — not even the general block can be identified) from block-level residual uncertainty (F09 — the block is known to be organic, but a specific organic syndrome cannot be specified) — a cross-chapter boundary check, since both are genuine residual categories that exist for the same underlying reason (real, exhausted missing information, never a convenience default) but at two different levels of the classification hierarchy.

Only comparisons involving a currently available category appear here. As more categories are authored, more comparison pairs will appear.