Clinical Reasoning

Aids to Undergraduate Pediatrics

CTAC — Common Things Are Common Mechanism Over Memorisation Day-1 House Officer Ready
Practice changes, but principles remain

Philosophies and Frameworks for Mental Structuring
Not lists for memorising

Structured ways of reasoning about pediatric medical problems that will serve you in the wards long after you have forgotten any particular fact.

The Principles
Common things are common — When you hear hoofbeats, think horse — not zebra.
Before thinking outside the box — make sure you master what's inside it.

Visit–Revisit

Clinical Assessment Is Not a Linear Process

Ask. Examine. Think. Revisit. Refine.
Clerking order is a communication format — not a thinking process. Good clinicians loop.
This model explains how to do clerking in an iterative process.

Professional Translation

From Patient Experience to Doctors' Language

Patients describe their experience in their language — not doctors' language.
This model explains how to listen to the patient's story, identify the relevant information, and structure it into a coherent clinical history.

Key Questions

The Art of Asking the Right Questions

Powerful discriminating questions outperform many vague ones.
This model explains how to ask discriminating questions that will guide clinical reasoning and narrow the differential diagnosis and plan of management.

Precision . Modifiers

No naked nouns in clinical medicine.

If you stop at the noun — you cannot diagnose.
This model explains how adjectives are not just embellishments — they are essential modifiers that can change the entire differential diagnosis.

Patient Story to Clinical History

Don't Repeat Words — Construct Meaning

Patients tell stories. Clinicians take histories.
This model explains how to listen to the patient's story, identify the relevant information, and structure it into a coherent clinical history.

Details to Abstraction

The better the summary, the sharper the differentials

A good summary explains everything in a few sentences.
This model explains how to distill a complex clinical case into a concise summary that captures the essential information and guides clinical reasoning.

Clinical Severity

Management Planning Needs Severity Assessment

Severity is a clinical judgement. This model explains the importance of assessing and communicating severity effectively to colleagues and seniors.

Differential Diagnosis

How to Think, Not Just List

A step-by-step approach to differential diagnosis. Apply this to every diagnosis on your list. Rank, don't list. Consider negative findings. And always ask — why?

Investigations

Every Investigation Must Answer a Clinical Question

This framework explains decision making in doing investigations — from formulating a clinical question to choosing the right test to interpreting results in context.

Three Clinical States

Chronic Diseases with Acute Exacerbations

Classify the state before you act. The acute flare is not bad luck — it is the consequence of failed maintenance. One model, every chronic disease.

Predict–Treat–Reassess

Think Before the Next Move

Every treatment decision needs a defined endpoint.
This model teaches you when to start, when to stop, and when to escalate — without guessing.

Raw–Factory–Loss

When something low, the problem is at one of three sites

When something in the blood is low, ask only three questions. This model applies to albumin, haemoglobin, platelets, and clotting factors — a single framework, four clinical scenarios.

Compensation Principle

When soldiers die at the frontier, reserves are deployed

Do not memorise "reticulocytes increased." Understand why. The bone marrow is central command — when soldiers fall at the frontier, reserves are deployed. When no reserves appear, the factory is destroyed.

Coming Soon

The Anaemia Workup

A step-by-step approach to investigating anaemia — from MCV to reticulocyte count to bone marrow.

In preparation

Bleeding Disorders

Platelet plug vs. coagulation cascade — when to suspect which, and how to read the coagulation screen.

In preparation

The Peripheral Blood Film

What each abnormal cell tells you — schistocytes, target cells, hypersegmented neutrophils, and more.

In preparation