The MRCGP AKT does not just test whether you know clinical facts — it tests whether you can apply clinical tools to patient scenarios under time pressure. Clinical calculators are directly examined: you will be given a clinical vignette with enough data to calculate a score, and the question will ask what the score means and what the next management step should be.
If you cannot rapidly calculate a QRISK3 threshold implication, a CHA₂DS₂-VASc anticoagulation decision, or a CURB-65 management pathway, you will lose marks on questions that are entirely predictable and entirely preparable.
These are the 10 calculators you must know — with worked examples, NICE references, and links to practise each one on iatroX Calculators.
1. NEWS2 — National Early Warning Score 2
What it does: Aggregates six physiological parameters (respiratory rate, SpO₂, systolic BP, pulse rate, consciousness, temperature) into a single score indicating clinical deterioration risk.
AKT relevance: Interpreting NEWS2 scores and knowing the escalation response. NEWS ≥5 triggers the sepsis screening pathway (NICE NG51). NEWS ≥7 triggers emergency response. The single-parameter-of-3 trigger (any single parameter scoring 3) requires urgent clinical review even if the total NEWS is lower.
The trap: Scale 2 for COPD patients. Patients with a target SpO₂ of 88-92% should be scored on Scale 2 — using Scale 1 in these patients generates falsely elevated scores and inappropriate escalation.
NICE reference: NICE NG51 (sepsis), RCP NEWS2 guidance. Calculate NEWS2 on iatroX.
2. CHA₂DS₂-VASc — AF Stroke Risk
What it does: Estimates annual stroke risk in patients with non-valvular atrial fibrillation.
AKT relevance: Anticoagulation decision-making. NICE NG196: anticoagulate if score ≥2 in males or ≥3 in females. DOAC first-line over warfarin. The AKT frequently presents AF patients and asks whether anticoagulation is indicated.
Worked example: 72-year-old male with AF, hypertension, and diabetes. C (CHF): 0. H (hypertension): 1. A₂ (age ≥75): 2. D (diabetes): 1. S₂ (stroke/TIA): 0. V (vascular disease): 0. A (age 65-74): already counted in A₂. Sc (sex — female): 0. Score: 4. Anticoagulation recommended.
Pair with: HAS-BLED for bleeding risk. Calculate CHA₂DS₂-VASc on iatroX.
3. QRISK3 — Cardiovascular Disease Risk
What it does: Estimates 10-year CVD risk using UK-specific variables.
AKT relevance: Statin initiation threshold. NICE CG181: offer atorvastatin 20mg when QRISK3 ≥10% after shared decision-making. The AKT presents CVD risk scenarios and asks about management thresholds.
Key point: Know that QRISK3 (not ASCVD, not Framingham) is the UK standard. The 10% threshold (not 7.5%, not 20%) is the NICE cutoff.
NICE reference: NICE CG181. Calculate QRISK3 on iatroX.
4. CKD-EPI — Estimated Glomerular Filtration Rate
What it does: Estimates GFR from serum creatinine, age, and sex. Used for CKD staging.
AKT relevance: CKD staging (G1-G5), drug dose adjustment thresholds, and referral criteria. NICE NG203: refer to nephrology if eGFR <30 (G4-G5) or sustained decline of ≥25% or ≥15 mL/min within 12 months.
Key point: Know the KDIGO staging grid (GFR categories G1-G5 × albuminuria categories A1-A3) and which combinations are "green" (monitor) vs "red" (refer).
NICE reference: NICE NG203. Calculate CKD-EPI on iatroX.
5. FIB-4 — Liver Fibrosis Index
What it does: Estimates liver fibrosis risk using age, AST, ALT, and platelets. First-line non-invasive fibrosis test in the NICE NAFLD pathway.
AKT relevance: NAFLD assessment pathway. NICE NG49: FIB-4 <1.30 = low risk (reassure), 1.30-2.67 = indeterminate (further assessment — NAFLD Fibrosis Score or FibroScan referral), >2.67 = high risk (refer to hepatology).
The trap: Indeterminate results are the most commonly tested scenario — the AKT asks what to do next, not just how to interpret the number.
NICE reference: NICE NG49. Calculate FIB-4 on iatroX.
6. CURB-65 — Pneumonia Severity
What it does: Scores community-acquired pneumonia severity: Confusion, Urea >7, Respiratory rate ≥30, Blood pressure (systolic <90 or diastolic ≤60), Age ≥65.
AKT relevance: Admission decision and antibiotic selection. Score 0-1: consider home treatment with oral amoxicillin. Score 2: consider hospital admission. Score 3-5: consider ICU assessment and IV antibiotics.
Key point: Know the BTS/NICE pathway, not the ATS/IDSA pathway. The antibiotic recommendations differ.
NICE reference: NICE NG138, BTS CAP guidelines. Calculate CURB-65 on iatroX.
7. Wells PE Score — Pulmonary Embolism Probability
What it does: Estimates pre-test probability of PE. Score ≤4: PE unlikely → D-dimer. Score >4: PE likely → CTPA.
AKT relevance: The PE diagnostic pathway per NICE NG128. The AKT presents patients with pleuritic chest pain and asks for the appropriate investigation — and the answer depends on the Wells score determining whether you go to D-dimer or straight to imaging.
The trap: The "alternative diagnosis less likely" criterion (3 points) is subjective and the most commonly misapplied element.
NICE reference: NICE NG128. Calculate Wells PE on iatroX.
8. PHQ-9 — Depression Severity
What it does: 9-item questionnaire scoring depression severity: 0-4 minimal, 5-9 mild, 10-14 moderate, 15-19 moderately severe, 20-27 severe.
AKT relevance: Treatment threshold. NICE NG222 stepped care: score ≥10 (moderate+) typically warrants discussion of antidepressant therapy alongside psychological therapy. Know the stepped care model and which interventions correspond to which severity level.
The critical point: Item 9 (suicidal ideation). If positive, a specific safety assessment is required before proceeding to treatment discussions. The AKT may present a PHQ-9 with item 9 positive and ask what the most appropriate immediate action is — the answer is safety assessment, not prescribing an SSRI.
NICE reference: NICE NG222. Calculate PHQ-9 on iatroX.
9. AUDIT-C — Alcohol Use Screening
What it does: 3-item screening tool for hazardous drinking. Score ≥5: positive screen — proceed to full AUDIT or brief intervention.
AKT relevance: Screening and brief intervention in primary care. NICE PH24 (alcohol-use disorders): AUDIT-C as the recommended screening tool in primary care. Know the scoring, the threshold, and the brief intervention structure.
NICE reference: NICE PH24. Calculate AUDIT-C on iatroX.
10. FRAX — Fracture Risk Assessment
What it does: Estimates 10-year probability of major osteoporotic fracture and hip fracture. Uses age, sex, BMI, previous fracture, parental hip fracture, smoking, alcohol, glucocorticoids, rheumatoid arthritis, secondary osteoporosis.
AKT relevance: Osteoporosis management pathway. NOGG guidance (referenced by NICE): FRAX score determines whether to treat, investigate further (DXA), or reassure. The AKT presents postmenopausal women with risk factors and asks about the appropriate next step.
Key point: FRAX without DXA gives the initial risk category. If the result falls in the "intermediate" zone, DXA is indicated to refine the estimate. FRAX with femoral neck T-score refines the risk and determines treatment.
NICE reference: NICE CG146 (being updated), NOGG guidance. Calculate FRAX on iatroX.
How to Use These for AKT Revision
Do not just memorise the scoring criteria — practise using each calculator with clinical vignettes until the scoring and interpretation are automatic. Open iatroX Calculators, work through scenarios, and verify the NICE management pathway for each result band.
Then test yourself on the iatroX MRCGP AKT Q-Bank (free) — which includes adaptive questions testing calculator application. The combination of calculator practice and Q-bank testing ensures you can both calculate and interpret under exam conditions.