Guided Mastery Path · Orient

Step 1 of 10: Block orientation

This is your path progress — how far you've moved through the recommended sequence. It is not a measure of what you've actually mastered; see "Your mastery evidence" further down for that.

What F99 covers, why it is organised the way it is, and how its 1 categories relate to one another.

F99 is used only when the information available does not support assigning a presentation to any of Chapter V's ten substantive blocks — not merely when a specific category within an already-identified block cannot yet be pinned down. It has no fourth-character subdivision in this classification basis: it is a single three-character residual code for the whole chapter, the last resort after every other, more specific classification has genuinely been checked and ruled out or found inapplicable for lack of information.

Why this mattersF99 sits at the top of a hierarchy of residual categories this product already teaches at the block level (F09, F29, F99's own near-neighbours F19.9/F39/F48.9/F59/F69/F79/F89/F98.9): each 'unspecified' code exists for a genuine situation where real information is missing, never as a shortcut for a vignette that simply takes more effort to work through. F99 raises the stakes on that same lesson one level higher — reaching for it before genuinely checking whether the presentation fits a specific block is the same convenience-default error already taught for the block-level unspecified categories, just applied at the level of the whole chapter. Because F99 is the classification of last resort for the entire chapter, using it prematurely risks losing specific, clinically useful information that was already available.

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All ten steps

Orient
Block orientation
What F99 covers, why it is organised the way it is, and how its 1 categories relate to one another.
Current step
Orient
Classification map
A quick-reference map of all 1 F99 codes and titles, so you know the terrain before going deep on any one of them.
Foundations
Foundational concepts and cautions
The core diagnostic question this block answers, and the safety cautions that apply to every category in it.
Foundations
Worked reasoning example
A full worked example of classification reasoning, step by step, using the anchor category F99.
Learn
Category learning units
Open each of the 1 category learning units in turn — this step tracks your progress across all of them.
Compare
Boundary comparisons
Work through the Boundary Comparison Lab — what overlaps, what discriminates, and the most common learner error for each pair.
Practise
Progressive case practice
The Case Lab, including the staged Type C/D cases where new information arrives after your first judgement.
Repair
Misconception repair
The Misconception Repair Lab: the tempting shortcut, why it fails, the better rule, and a short transfer check.
Test
Mixed Mastery Check
Novel, mixed-order transfer items across all six reasoning dimensions, with a formative report at the end.
Review
Session Summary and revision
Your Session Summary, plain-language state per mastery dimension, and where to go for Rapid Revision.

Jump to any step at any time — this path never locks you in.

Your mastery evidence (not the same as path progress)

This reflects actual answers from the Case Lab, Decision Lab and Mastery Check this session — it does not move just because you've opened more steps above.

Structure Not attempted

Concept Not attempted

Evidence Not attempted

Boundary Not attempted

Uncertainty Not attempted

Transfer Not attempted

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