1. Exchangeability (Ignorability) 🔎 What it means: After adjusting for the observed covariates X, the treated and untreated groups are...

1 Why Observational Data Are Harder Than RCTs RCT privilege What you lose  in an observational study Investigator controls treatment →...

Causal Inference inside an RCT  – STATA-First Edition 0 Glossary of Key Abbreviations Short-form Stands for Meaning in this document R...

The Three E’s of Quantitative Research Term One-line definition Where it “lives” Simple example (blood-pressure drug) Estimand The...

1 Why Causality Matters Correlation  → two variables move together. Causation  → changing  exposure X  would change  outcome Y  for the...

Introduction Time-to-event studies frequently rely on Cox proportional-hazards regression because it requires no a priori specification...

Table of Different slices of risk in time-to-event research : Concept Core question answered Typical notation (plain text) Where is it...

Introduction Clinical and public-health investigations often focus not only on whether  an outcome occurs but also on when  it occurs....

1. Declaring Survival Data with stset Purpose: The stset command in Stata designates your dataset as survival (time-to-event) data. This...

Introduction Time-to-event analysis, commonly referred to as survival analysis, is a cornerstone methodology in clinical research and...

Stata’s merge and append are among the first data management tools you’ll use in real clinical research. But when should you use each?...

1. Diagnosis & Classification (2019 EULAR/ACR) Step How to Apply at the Bedside Key Numbers & Rules Entry criterion Confirm ANA by...

1 Pathophysiology & Clinical Presentation Key point Polymyositis (PM) Dermatomyositis (DM) Immune driver CD8⁺ T-cell–mediated myofibre...

1. Confirming the Diagnosis Step How you do it Exam pearls 1 A. Clinical suspicion Look for skin thickening , Raynaud phenomenon, puffy...

1. Making the Diagnosis Step-wise approach, you can reproduce on the wards or in a viva: What you do Why it matters “Exam-ready” tips 1....

A Hepatitis A (HAV) Investigate Serum anti-HAV IgM  → acute infection. Treatment Purely supportive ; almost always self-limited....

1 Hepatitis B (HBV) Investigate Screen:  HBsAg, anti-HBs, total anti-HBc ± IgM anti-HBc (if acute suspected) If HBsAg + :  HBeAg, HBV DNA...

Below is a stage-by-stage “when to treat & how to treat” roadmap  for both hepatitis B (HBV) and hepatitis C (HCV). I highlight triggers...

Below is a self-contained, exam-ready deep dive  on reading positive (+)  and negative (–)  viral-hepatitis profiles. I keep the...

Introduction In clinical epidemiology, quantifying how often events occur, such as complications, readmissions, or adverse effects, is...

Introduction In clinical research, the concept of rate  underpins our ability to quantify the frequency of events, particularly in...