Biostatistics & Epidemiology
11-13%of exam
Sensitivity/SpecificityNNT/NNHStudy DesignBias & Confounding
Ethics, Legal & Patient Safety
7-9%of exam
Capacity & ConsentMinor ConsentPatient SafetyRoot Cause Analysis
Pharmacology & Foundational Science
Not publishedof exam
Reversal AgentsDrug InteractionsPharmacokineticsCYP450
CCS Case Simulation Strategy
Not publishedof exam
Order EntryClock ManagementFollow-up OrdersScoring Domains
Cardiovascular System
9-11%of exam
ACS/ECGHypertensionAtrial FibrillationMurmurs
Pulmonary & Critical Care
8-10%of exam
CURB-65Wells/PERCARDS BerlinCOPD Exacerbation
Gastrointestinal System
6-8%of exam
GI Bleed TimingHepatic EncephalopathyPancreatitisAscites
Renal & Urinary System
4-6%of exam
Anion GapHyponatremiaDKA ElectrolytesAcid-Base
Infectious Disease & Heme/Onc
6-8%of exam
Sepsis-3/qSOFAFebrile NeutropeniaAnemia WorkupVirchow's Triad
Endocrine System
5-7%of exam
Diabetes ManagementThyroid LabsDKA vs HHSA1c Goals
Neurology & Special Senses
8-10%of exam
Stroke tPA WindowSubarachnoid HemorrhageNPH TriadBotulism
Psychiatry & Behavioral Health
4-6%of exam
Serotonin SyndromeNMSBenzo WithdrawalAlcohol Withdrawal
OB/GYN & Reproductive Health
7-9%of exam
PreeclampsiaEctopic PregnancyPregnancy UTIhCG Trends
Pediatrics & Preventive Care
1-3%of exam
Vaccine ScheduleGrowth & DevelopmentLead ScreeningWell-Child Care
Musculoskeletal System
5-7%of exam
Gout vs PseudogoutSeptic ArthritisArthrocentesisCrystal Analysis
Dermatology
4-6%of exam
SJS/TENMelanoma ABCDEDrug EruptionsBSA Staging
Quick Facts
- Exam
- USMLE Step 3
- Body
- FSMB / NBME
- Format
- 2-day: FIP, ACM, CCS
- MCQs
- 412 (232 Day1 + 180 Day2)
- CCS Cases
- 13-14, Day 2 only
- Time
- ~16h total (7h + 9h)
- Pass Score
- 200 (3-digit scale)
- Pass Rate
- 96% MD / 97% DO
- Level
- Final USMLE licensing step
- Fee
- $955 (2026)
SnNout and SpPin Test Rules
High sensitivity rules out; high specificity rules in
SnNout: sensitive, negative, outSpPin: specific, positive, in
RCT/Cohort vs Case-Control
RCT/cohort
- Report relative risk
- Exposure forward
Case-control
- Report odds ratio
- Outcome backward
Design dictates measure
Test Statistics & Predictive Value
- Sensitivity
- TP/(TP+FN); SnNout
- Specificity
- TN/(TN+FP); SpPin
- PPV
- TP/(TP+FP), prevalence-dependent
- NPV
- TN/(TN+FN), prevalence-dependent
- NNT
- 1/ARR, lower is better
- NNH
- 1/ARI, lower is worse
- Relative risk
- Cohort/RCT studies only
- Odds ratio
- Case-control studies only
Study Design & Bias
- Confounder
- Linked to exposure and outcome
- Effect modifier
- Different effect by subgroup
- Type I error
- Alpha, false positive
- Type II error
- Beta, false negative
- Power
- 1-beta, detects true effect
- RCT
- Gold standard for causation
- Cohort study
- Exposure forward to outcome
- Case-control
- Outcome backward to exposure
Capacity, Consent & Confidentiality
- Capacity
- Communicate, understand, appreciate, reason
- Autonomy
- Refusal trumps beneficence
- Minor consent
- Emergency, STI, emancipated minor
- Surrogate order
- Spouse, adult child, parent
- Confidentiality break
- Duty to warn/protect
- Advance directive
- Overrides family wishes
Patient Safety & Systems
- Swiss cheese model
- System fault, not individual
- Root cause analysis
- Retrospective systems review
- Sentinel event
- Unexpected death or serious harm
- Near miss
- Error caught before harm
- PDSA cycle
- Plan-Do-Study-Act quality improvement
Dabigatran vs Factor Xa Reversal
Dabigatran
- Idarucizumab reverses
- Direct thrombin inhibitor
Factor Xa inhibitors
- Andexanet alfa reverses
- Apixaban, rivaroxaban
Match antidote to target
Anticoagulant Reversal Selection
- Dabigatran bleeding→Idarucizumab
- Factor Xa inhibitor bleeding→Andexanet alfa
- Warfarin, life-threatening bleed→4-factor PCC + vitamin K
- Heparin overdose/bleeding→Protamine sulfate
Antidotes & Reversal Agents
- Dabigatran
- Idarucizumab reverses
- Factor Xa inhibitors
- Andexanet alfa reverses
- Warfarin (urgent)
- 4-factor PCC + vitamin K
- Heparin
- Protamine sulfate reverses
- Opioids
- Naloxone reverses
- Benzodiazepines
- Flumazenil (caution: seizures)
- Acetaminophen
- N-acetylcysteine reverses
- Beta-blocker overdose
- Glucagon reverses
Drug Interactions & Mechanisms
- CYP3A4 inhibitor + statin
- Raises myopathy risk
- Protein-binding displacement
- Raises free-drug fraction
- ACE inhibitor cough
- Bradykinin buildup; switch ARB
- Warfarin necrosis
- Protein C depletes first
- Serotonin syndrome trigger
- SSRI plus MAOI/tramadol
CCS Order Entry & Timing
- Order entry
- Free-text, pick autocomplete
- Clock advance
- Move to next needed time
- Follow-up orders
- Schedule reassessment, not just treat
- Case length
- 10-20 simulated minutes
- Location changes
- Move to ICU when unstable
- Scoring domains
- Diagnosis, therapy, timing, sequencing
HCM vs Aortic Stenosis Murmur
HCM
- Louder with Valsalva
- Softer with squatting
Aortic stenosis
- Softer with Valsalva
- Louder with squatting
Preload response is opposite
Acute Chest Pain Pathway
- ST elevation present→Emergent reperfusion(PCI <90 min preferred)
- ST depression V1-V3→Suspect posterior MI(Confirm posterior leads)
- Troponin positive, no ST changes→NSTEMI pathway(Anticoagulate + risk stratify)
- Low-risk, normal troponin→Outpatient stress test(If reassuring exam)
Coronary & ECG Patterns
- Posterior MI
- ST depression, tall R, V1-3
- STEMI door-to-balloon
- 90 minute goal
- STEMI door-to-needle
- 30 minute goal (lytics)
- NSTEMI/UA
- Troponin up, no ST elevation
- CABG preferred
- 3-vessel or left main disease
AF Anticoagulation Decision
- CHA2DS2-VASc ≥2, men→Anticoagulate
- CHA2DS2-VASc ≥3, women→Anticoagulate
- Valvular AF (mechanical valve)→Warfarin only(Not DOAC)
- Low score, no other RF→Consider no anticoagulation
Hypertension & Arrhythmia Targets
- BP goal
- <130/80 most adults (ACC/AHA)
- Stage 2 HTN
- ≥140/90 mmHg
- CHA2DS2-VASc ≥2
- Anticoagulate (men)
- CHA2DS2-VASc ≥3
- Anticoagulate (women)
- DOAC preferred
- Over warfarin, nonvalvular AF
- HCM murmur
- Louder Valsalva, softer squat
- AS murmur
- Softer Valsalva, louder squat
CURB-65 Pneumonia Severity Score
Confusion, Urea, Respiratory rate, Blood pressure, Age 65
ConfusionUrea >19RR ≥30BP <90/60Age ≥65
Suspected PE Workup
- Low Wells score→Order D-dimer
- D-dimer negative→PE excluded
- Moderate/high Wells→CT pulmonary angiography(Skip D-dimer)
- PERC all negative→No further testing
Pulmonary Risk Scores
- CURB-65 ≥2
- Admit for CAP
- CURB-65 ≥3
- Consider ICU care
- Wells low + neg D-dimer
- PE effectively excluded
- Wells moderate/high
- CT-PA, skip D-dimer
- PERC all negative
- No further PE workup
- Berlin ARDS
- PaO2/FiO2 ≤300, bilateral opacities
- ARDS severity
- Mild 200-300, severe ≤100
COPD & Asthma Management
- COPD exacerbation triad
- Bronchodilator, steroid, antibiotic
- Antibiotic trigger
- Purulent sputum or vent need
- Home O2 criteria
- PaO2 ≤55 or SpO2 ≤88%
- Status asthmaticus
- Silent chest, no air movement
GI Bleeding & Liver Disease
- Upper GI bleed scope
- Within 24h, after resuscitation
- Hepatic encephalopathy
- Lactulose is first-line
- Refractory HE
- Add rifaximin
- Pancreatitis diagnosis
- 2 of 3 criteria met
- Lipase threshold
- >3x upper limit normal
- SAAG ≥1.1
- Portal hypertension cause
High Anion Gap Causes (MUDPILES)
Methanol, Uremia, DKA, Paraldehyde, Iron-INH, Lactic, Ethylene-glycol, Salicylates
MethanolUremiaDKAParaldehydeIron/INHLactic acidosisEthylene glycolSalicylates
Electrolytes & Acid-Base
- Anion gap
- Na−Cl−HCO3, normal 8-12
- MUDPILES
- High anion gap causes
- Hyponatremia correction
- ≤8 mEq/L per 24h
- Overcorrection risk
- Osmotic demyelination syndrome
- DKA potassium rule
- Replete K+ before insulin
- DKA insulin hold
- Hold if K+ below 3.3
Virchow's Triad for Thrombosis
Stasis, endothelial injury, and hypercoagulability cause clots
Stasis: immobilityInjury: vessel wall damageHypercoagulability: clotting factors
Iron Deficiency vs Thalassemia Trait
Iron deficiency
- High RDW
- Low ferritin
Thalassemia trait
- Normal RDW
- Low Mentzer index
RDW variability is key
Sepsis & Infection Thresholds
- qSOFA ≥2
- RR≥22, altered mentation, SBP≤100
- Sepsis-3
- Infection plus organ dysfunction
- Septic shock
- Lactate>2 plus pressors needed
- Febrile neutropenia
- Antibiotics within 1 hour
- Empiric agent
- Cefepime or pip-tazo
qSOFA Sepsis Screening Criteria
Respiratory rate, altered mentation, and low systolic BP
RR ≥22/minAltered mentationSBP ≤100 mmHg
Hematology & Oncology
- Iron deficiency
- High RDW, low ferritin
- Thalassemia trait
- Normal RDW, low Mentzer
- Mentzer index
- MCV/RBC <13, thalassemia
- Virchow's triad
- Stasis, injury, hypercoagulability
Subclinical vs Overt Hypothyroidism
Subclinical
- High TSH
- Normal free T4
Overt
- High TSH
- Low free T4
Free T4 makes diagnosis
DKA Fluid-Insulin-Potassium Sequence
- K+ below 3.3→Hold insulin, replete K+
- K+ 3.3-5.3→Start insulin + K+ together
- K+ above 5.3→Start insulin, monitor K+
- Glucose reaches ~200→Add dextrose, continue insulin
Thyroid & Diabetes Management
- Metformin
- First-line for T2DM
- Subclinical hypothyroid
- High TSH, normal free T4
- Overt hypothyroid
- High TSH, low free T4
- DKA vs HHS
- Ketoacidosis vs extreme glucose
- A1c goal
- <7% most adults
Normal Pressure Hydrocephalus Triad
Wet, wobbly, and wacky — incontinence, gait, cognition
Wet: incontinenceWobbly: gait apraxiaWacky: dementia
Acute Ischemic Stroke Pathway
- Within 4.5h, CT clear→Give IV tPA(If BP <185/110)
- BP too high→Lower before tPA(Labetalol/nicardipine)
- Large vessel occlusion→Add mechanical thrombectomy(Up to 24h select cases)
- Beyond window/contraindicated→Antiplatelet + supportive care
Stroke & Neuro Emergencies
- tPA window
- 4.5h from last known well
- tPA BP limit
- <185/110 mmHg
- Worst headache ever
- CT then LP for SAH
- CT sensitivity drop
- After 6-12h for SAH
- NPH triad
- Wet, wobbly, and wacky
- NPH first response
- Gait improves first
- Botulism
- Descending paralysis, antitoxin
Serotonin Syndrome vs NMS
Serotonin syndrome
- Hyperreflexia, clonus
- Rapid onset (hours)
NMS
- Lead-pipe rigidity
- Slow onset (days)
Reflexes up vs rigid
Psychiatric Emergencies
- Serotonin syndrome
- Hyperreflexia, clonus, rapid onset
- NMS
- Lead-pipe rigidity, slow onset
- Benzo withdrawal
- Seizure risk; taper, don't stop
- Alcohol withdrawal
- Peaks 24-72h, DTs risk
OB Emergencies & Pregnancy Risk
- Preeclampsia, severe
- BP ≥160/110 plus symptoms
- Eclampsia prophylaxis
- Magnesium sulfate is first-line
- hCG rise rule
- ≥53% in 48h is normal
- Suboptimal hCG rise
- Rule out ectopic pregnancy
- UTI in pregnancy
- Avoid fluoroquinolones
- Near-term UTI
- Avoid nitrofurantoin, sulfa
Pediatric & Preventive Care
- MMR dose 1
- 12-15 months
- MMR dose 2
- 4-6 years
- MMR contraindication
- Pregnancy, immunosuppression
- Lead screening
- 12 and 24 months
Gout vs Pseudogout Crystals
Gout
- Negative birefringence
- Needle-shaped
Pseudogout
- Positive birefringence
- Rhomboid-shaped
Birefringence sign flips
Joint & Crystal Disease
- Gout crystals
- Negative birefringent, needle-shaped
- Pseudogout crystals
- Positive birefringent, rhomboid
- Septic arthritis
- Arthrocentesis before antibiotics
- Septic WBC threshold
- >50,000/µL, PMN predominant
SJS vs TEN
SJS
- <10% BSA sloughing
- Better prognosis
TEN
- >30% BSA sloughing
- Higher mortality
BSA percentage decides severity
Dermatologic Emergencies
- SJS
- <10% BSA sloughing
- SJS/TEN overlap
- 10-30% BSA sloughing
- TEN
- >30% BSA sloughing
- SJS/TEN first step
- Stop the offending drug
- ABCDE melanoma
- Asymmetry, border, color, diameter, evolving
Common Traps
Sensitivity ≠ specificity direction
Sensitivity rules out disease ≠ Specificity rules in disease
Relative risk ≠ odds ratio
RR needs cohort/RCT design ≠ OR needs case-control design
System error ≠ individual blame
Latent system defect at fault ≠ Fix the process, not person
CURB-65 ≠ qSOFA
CURB-65 is pneumonia-specific ≠ qSOFA is general sepsis screen
Idarucizumab ≠ andexanet alfa
Idarucizumab reverses dabigatran only ≠ Andexanet alfa reverses factor Xa
Subclinical ≠ overt hypothyroidism
Subclinical has normal free T4 ≠ Overt has low free T4
SJS ≠ TEN severity
SJS is under 10% BSA ≠ TEN is over 30% BSA
Hyponatremia correction ≠ unlimited
Max 8 mEq/L per 24h ≠ Faster risks brain demyelination
Last Minute
- 1.412 MCQs: 232 Day1, 180 Day2
- 2.13-14 CCS cases, Day 2 only
- 3.Pass score is 200, 3-digit
- 4.CCS: free-text order entry, autocomplete
- 5.Schedule follow-up orders in CCS
- 6.BP goal <130/80 most adults
- 7.tPA window is 4.5 hours
- 8.tPA needs BP <185/110
- 9.DKA: replete K+ before insulin
- 10.Hyponatremia: correct ≤8 mEq/L/24h
- 11.CURB-65 ≥2 means admit
- 12.CHA2DS2-VASc ≥2 (men) anticoagulate
- 13.Idarucizumab for dabigatran, not Xa
- 14.SJS <10% BSA, TEN >30%
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