Misdiagnosis solicitor: what they do and how to find one

Published 18 May 2026

TL;DR

A misdiagnosis solicitor is a clinical negligence specialist who handles claims arising from incorrect, missed, or delayed diagnoses
The solicitor obtains medical records, instructs independent experts, and assesses both whether the diagnosis fell below the Bolam standard and whether the misdiagnosis caused harm
Most misdiagnosis solicitors work on a conditional fee basis: no fees payable if the claim does not succeed
A misdiagnosis solicitor will advise on prospects of success before any commitment is made; not every misdiagnosis is a viable legal claim
The time limit is three years from the date of knowledge; early advice is important

A misdiagnosis solicitor is a clinical negligence lawyer who handles claims where a patient was given an incorrect diagnosis, had the correct diagnosis missed entirely, or waited too long for the correct diagnosis to be made. These are among the most common and most significant categories of clinical negligence claim. The role of the misdiagnosis solicitor is to assess whether the diagnostic failure fell below the required standard of care, whether that failure caused harm, and whether the claim is legally viable.

What does a misdiagnosis solicitor do?

A misdiagnosis solicitor carries out a structured assessment of the clinical and legal issues from first instruction to settlement or judgment.

Initial case assessment: the solicitor takes a detailed account of the treatment and the harm suffered, identifies the relevant clinical records, and advises on whether the facts are capable of supporting a claim. This assessment considers both the legal merits (breach and causation) and the likely value of the claim. A Bolam breach that caused only minor and fully-resolved harm may not be economically viable as a standalone claim.

Records and evidence: the solicitor obtains all relevant clinical records: GP notes, hospital records, imaging, pathology, referral letters, and correspondence between clinicians. In misdiagnosis cases, the sequence of events recorded in the notes is often central to both breach and causation.

Expert evidence: an independent medical expert in the relevant specialism is instructed to review the records and report on whether the defendant clinician's diagnosis (or failure to diagnose) fell below the Bolam standard. In claims where the misdiagnosis caused a condition to progress, additional experts address causation: what the patient's position would have been with a correct and timely diagnosis.

Pre-action protocol: the solicitor follows the Pre-Action Protocol for the Resolution of Clinical Disputes. Once expert evidence supports the claim, a Letter of Claim is sent to the defendant setting out the allegations in detail. The defendant has four months to respond.

Settlement or proceedings: most misdiagnosis claims resolve without a court hearing. The misdiagnosis solicitor negotiates with the defendant or NHS Resolution on quantum once liability is admitted or established.

What types of misdiagnosis does a solicitor handle?

Misdiagnosis solicitors handle the full range of diagnostic failures across every clinical setting.

Wrong diagnosis: the clinician diagnoses a condition the patient does not have, and the correct condition goes untreated. A patient treated for a psychiatric condition who is in fact having a stroke, or treated for gastroenteritis who has appendicitis, has been wrongly diagnosed.

Missed diagnosis: the clinician fails to identify any condition despite the patient presenting with symptoms that should have prompted investigation. A GP who dismisses symptoms that a responsible GP would have investigated is failing to diagnose.

Delayed diagnosis: the correct diagnosis is eventually made, but after a period of delay caused by a failure to investigate, refer, or act on results. Delayed diagnosis is the most common category and includes delayed cancer diagnosis, delayed diagnosis of cardiac conditions, and delayed diagnosis of infections such as meningitis and sepsis.

For a full explanation of how misdiagnosis claims are assessed and what needs to be proved, see the misdiagnosis claim guide. For the specific framework applicable to delayed diagnosis claims, see the delayed diagnosis guide.

How is a misdiagnosis solicitor claim funded?

Most misdiagnosis solicitors act under a conditional fee agreement (CFA). Under a CFA, the solicitor takes no fee if the claim does not succeed. If the claim succeeds, a success fee (capped at 25% of the damages awarded for pain, suffering, and past losses) is charged. After-the-event (ATE) insurance is taken out to cover the risk of adverse costs if the claim fails at a late stage.

Legal aid is not available for clinical negligence. Private funding is possible but most claimants use the conditional fee route. The practical effect is that a misdiagnosis solicitor bears the financial risk of pursuing a claim that fails. This means a solicitor working under a CFA will only take on claims with reasonable prospects of success: a natural filter that protects the claimant from investing time in a claim unlikely to succeed.

For a full explanation of how no win no fee funding works in clinical negligence, see the funding guide.

Viability of a misdiagnosis claim

Not every misdiagnosis is a viable legal claim. A misdiagnosis solicitor will assess viability on three axes.

Breach: did the diagnostic failure fall below what a responsible body of clinicians in the same specialism would have done? A difficult diagnosis in a presentation with atypical features may not constitute a breach even if the outcome was poor. A failure to follow NICE referral guidelines, or to act on a clearly abnormal result, more readily satisfies breach.

Causation: did the misdiagnosis cause harm that would not otherwise have occurred? A delayed diagnosis that made no difference to treatment or outcome does not cause actionable harm even if the delay was negligent. Where the delay caused a condition to progress to a more advanced stage, or where the wrong treatment was administered and caused an adverse reaction, causation is established.

Value: the claim must be worth pursuing. Legal proceedings involve substantial costs. A clear breach that caused a temporary injury resolving fully within weeks may not justify the expense of a contested clinical negligence claim. Most misdiagnosis solicitors advise frankly on value at the outset.

For time limits, see the time limits guide. For how the claims process works end to end, see the how to claim guide.

This page provides legal information, not legal advice. If you believe a misdiagnosis caused you harm, speak to a qualified misdiagnosis solicitor who specialises in clinical negligence.