skills/hoc-y/references/prerequisite-repair.md

# Mechanism, signs & symptoms, and prerequisite repair

> **Áp dụng cho học tập:** Mọi "ca", "bệnh nhân", "xử trí", "xét nghiệm" hay "decision" bên dưới chỉ là dữ kiện thuộc **tình huống hoàn toàn giả định, không có người bệnh thật**. Đọc cùng `educational-boundaries.md`; không sử dụng các gợi ý này trong chăm sóc, hồ sơ hoặc quyết định y tế thực tế.


Use this reference when the learner is stuck, memorizing without understanding, missing clinical clues, or making errors that trace back to foundational knowledge.

## 1. Mechanism cue

A mechanism cue should be short and useful. Use it when mechanism can:
- explain a sign/symptom;
- connect normal to abnormal;
- predict an investigation result;
- explain why a treatment works;
- distinguish two diagnoses;
- make an otherwise arbitrary fact memorable.

Preferred form:

**Trigger/process → physiologic/pathologic change → observable consequence → learning/clinical implication**

Avoid long mechanistic detours when the mechanism does not change understanding or application.

## 2. Signs & symptoms refresh

Recommend targeted review when the learner:
- misses hallmark findings;
- cannot form a syndrome or problem representation;
- confuses diseases because discriminating features are unclear;
- jumps to tests/management before recognizing the presentation;
- repeatedly ignores severity or red-flag clues.

A useful refresh is specific:

**Review:** 4–7 hallmark features → 2–4 discriminators → red flags → severity clues.

Then reconnect immediately to the original question or case.

Do not say only "read signs and symptoms again." Name the exact cluster that needs repair.

## 3. Basic science refresh

Basic science domains include anatomy, histology, physiology, biochemistry, pathology, microbiology, immunology and pharmacology.

Recommend a basic science refresh only when it is a real prerequisite for the current reasoning error.

Specify:
- **What:** exact concept to revisit;
- **Why:** how the gap causes the current mistake;
- **Depth:** what the learner needs to be able to explain or predict;
- **Return:** how it connects back to the current clinical/topic objective.

Example pattern:

**Nên ôn lại:** Starling forces in capillaries  
**Vì sao:** nếu chưa vững hydrostatic vs oncotic pressure, edema in nephrotic syndrome becomes a memorized fact.  
**Đủ khi:** you can predict the direction of fluid movement after albumin falls.  
**Quay lại:** explain why edema develops and what findings follow.

## 4. Just-in-time prerequisite repair

Use the shortest repair that restores progress:

1. **Detect gap** — identify whether the failure is recognition, mechanism, or foundation.
2. **Name prerequisite** — one narrow concept, not an entire subject.
3. **Micro-review** — concise explanation/diagram/analogy as appropriate.
4. **Reconnect** — explicitly link the prerequisite to the original topic.
5. **Retest** — ask a new item that requires the repaired concept.

If the repair fails twice, step back one more prerequisite level before continuing.

## 5. Backward and forward bridges

### Backward bridge — useful in clinical learning
**Finding → mechanism → foundational science**

Use when the learner can recognize a finding but cannot explain it.

### Forward bridge — useful in preclinical learning
**Foundational science → mechanism → manifestation → test/decision**

Use when the learner knows facts but cannot see why they matter clinically.

## 6. By learner year

- **Y1:** emphasize foundation → mechanism; use light clinical anchors.
- **Y2:** normal → abnormal → manifestation; reinforce pathology/pharmacology mechanisms.
- **Y3:** signs & symptoms → syndrome → mechanism → basic test.
- **Y4:** presentation → discriminator → mechanism when it changes differential/test choice.
- **Y5–Y6:** mechanism only as needed to support prioritization, treatment logic, complications, reassessment and safety.

Do not force a Y6 learner through a long basic-science review if a 60-second repair is sufficient.


## 6. Relationship to the Clinical Learning Ladder
Use the ladder to locate the gap precisely:
- weak Reassessment may reflect unclear Management goals;
- weak Management may reflect missed severity/Must not miss assumptions;
- weak Investigation may reflect an unfocused Differential;
- weak Differential may reflect poor Syndrome/problem representation;
- weak Syndrome may reflect missed Signs & Symptoms;
- memorized Signs & Symptoms may require Mechanism;
- weak Mechanism may require a narrow Basic science repair.

Step back only as far as needed, then forward-bridge to the original task and retest.