Both. But for different things.
NICE CKS is the authoritative UK primary care reference — approximately 400 clinical topics with evidence-graded management recommendations, updated systematically by NICE. CKS is what examiners expect your management plans to reflect. It is what ARCP panels trust. It is the ground truth for UK primary care guidelines. Free.
GPnotebook is the broad UK primary care reference — 30,000+ pages covering conditions, investigations, differentials, and clinical pearls. It is faster to navigate during consultations, covers far more topics than CKS, and includes education modules (GEMs), quizzes, and podcasts. Free tier available; Pro at £7.99/month adds CPD tracking and full access.
When to Use Each
Use CKS for management decisions. When you need to know the current NICE-recommended first-line treatment, referral threshold, investigation pathway, or safety-netting advice — CKS is authoritative. The AKT tests CKS-aligned management, so building the habit of checking CKS during daily practice directly improves your exam performance.
Use GPnotebook for quick clinical reference. When you need to check a differential diagnosis list, recall the features of an unfamiliar condition, or verify a normal range during a consultation — GPnotebook's 30,000-page library provides faster answers for broader queries than CKS's 400-topic structure.
The Known Caveat
GPnotebook's evidence quality can vary — some pages may not reflect the most current NICE guidance. For management decisions that affect patient care, verify against CKS or BNF. GPnotebook is excellent for broad reference but should not be treated as the definitive guideline source for prescribing or management decisions.
For the AKT specifically, CKS is more likely to reflect what examiners expect than GPnotebook — because AKT questions are designed to test NICE-aligned management.
Where iatroX Fits
CKS is authoritative. GPnotebook is broad. Ask iatroX provides citation-first answers grounded in NICE/CKS/BNF — combining the authority of CKS with the speed of a natural-language query in one interface. Ask a clinical question, get a cited guideline answer in seconds. Use alongside both CKS and GPnotebook.