Conditions Frequently Involved in Delayed Diagnosis Claims
Causation — The Core Challenge
Delayed diagnosis claims turn on causation as much as breach of duty. Even where a GP or hospital is shown to have unreasonably delayed a diagnosis, the claimant must prove that earlier diagnosis would have led to a materially better outcome:
- Cancer: an oncologist expert assesses the staging of the cancer at the time it should have been diagnosed versus when it was actually diagnosed. The difference in stage determines the difference in treatment and prognosis. If cancer was Stage 1 at the point it should have been referred and Stage 3 by the time of actual diagnosis, causation is generally strong.
- Stroke: a neurologist assesses whether the claimant would have received thrombolysis in time had presentation been recognised; and the neurological deficit attributable to the delay versus what would have persisted even with timely treatment.
- Sepsis: an infectious disease or intensive care expert assesses the "but for" counterfactual — would earlier antibiotic treatment have prevented the organ damage, amputation, or death?
- Where causation is uncertain on the balance of probabilities (50/50 cases), modified causation principles — such as material contribution to risk — may be available, though these are complex legal arguments requiring expert legal advice.
Frequently Asked Questions
What if my condition is now terminal — is it too late to claim?
No — a claim can still be pursued and is often more urgent in these circumstances. The claim can be brought by the patient themselves during their lifetime. Where the patient lacks capacity or is too ill to instruct a solicitor, a litigation friend can act on their behalf. Where the patient has died, an estate claim and fatal accident dependency claim can be pursued by the family. A specialist solicitor acts urgently in terminal illness cases to obtain interim payments and achieve settlement within the patient's lifetime where possible.
I was told the cancer was caught "early enough" — but I am still suffering. Can I claim?
Yes — even where the treating team tells you the delay made no difference, this is a self-interested assessment, not an independent legal determination. An independent oncologist will review the records and assess the staging at the point of delayed referral and at the actual point of diagnosis. If staging had progressed, the treatment was more aggressive, or the prognosis is materially worse than it would have been with earlier diagnosis, there may be a causation argument. The question is one for independent experts, not the treating team.
My GP saw me multiple times before diagnosing me — is that enough to claim?
Multiple consultations before diagnosis is significant evidence, but not automatically sufficient to establish negligence. The question is: at which consultation should a reasonable GP have referred or investigated? An independent GP expert reviews each consultation note, the symptoms presented, and the investigations (or investigations not performed) at each visit, and identifies the point at which the Bolam standard required action. If the GP dismissed the symptoms without adequate examination or investigation on multiple occasions, the case for breach is stronger.
What evidence do I need to bring a delayed diagnosis claim?
The key evidence is the medical records — all GP notes, hospital records, radiology reports, histology results, and referral correspondence. A solicitor obtains all records under GDPR. The claimant's own contemporaneous records — a diary or symptom log, printed appointment summaries, or messages to the GP — can be powerful supplementary evidence showing what symptoms were reported and when. If symptoms were described to the GP that should have triggered referral, but the records do not reflect this accurately, witness evidence from the patient and their family is also valuable.
How long does a delayed diagnosis claim take?
Medical negligence claims, including delayed diagnosis claims, typically take 2–4 years from instruction to settlement or trial. The time is spent obtaining records, commissioning expert liability and causation reports, sending the Letter of Claim, obtaining NHS Resolution's response (4 months), negotiating on liability and quantum, and litigating if settlement cannot be agreed. For terminal illness cases, a solicitor applies for expedition and pursues settlement as urgently as possible. Interim payments can be applied for at an early stage where financial need is demonstrated.