Records review versus independent medical examination: choosing the appropriate report type for causation in RTA claims

In personal injury and clinical negligence litigation arising from road traffic accidents (RTAs), the form of evidence required to establish causation depends on whether the central dispute concerns the existence of an injury, its mechanical derivation from the incident, or the subsequent trajectory of recovery. Instructing parties should assess whether the available documentary evidence provides a sufficient basis for a reasoned opinion or if a physical assessment of the claimant is required to resolve conflicting medical narratives.

The scope of a records-only review

A records review focuses on the chronological analysis of medical notes, imaging reports, and ambulance data to determine if a claimed injury is consistent with the documented trauma. This format is often appropriate where the diagnosis is well-established by contemporaneous hospital records and the dispute is limited to the mechanics of causation or the attribution of symptoms to a specific event. A practitioner undertaking such a review evaluates whether the clinical presentation recorded at the scene or in the emergency department aligns with the alleged mechanism of the RTA.

When a solicitor instructs an expert to perform an analysis of medical and historical documentation, the expert provides an opinion based on the standard of the relevant specialty without the requirement for a physical assessment. This approach assumes that the primary evidence is contained within the clinical and diagnostic records maintained during the immediate aftermath of the incident. If the records are incomplete, such as where initial imaging is absent or the attendance note is illegible, the expert must state these limitations clearly, as an opinion on causation may be difficult to sustain on incomplete information.

The role of the independent medical examination

An independent medical examination (IME) is often appropriate when the expert must evaluate physical signs, range of motion, or neurological deficits that are not adequately captured in the existing medical records. This is critical in RTA claims where the claimant reports ongoing symptoms, such as chronic pain or functional impairment, which lack a documented path of recovery. The examination allows the expert to test the reliability of reported symptoms against observed behaviour and validated clinical markers.

The examination serves to establish whether the physical findings support the claimant’s description of the injury’s impact on their daily life. It is the appropriate tool when the expert must form an opinion on prognosis, where the future trajectory of the condition remains uncertain. The physical examination facilitates the identification of features that might suggest the presence of pre-existing degenerative conditions which may contribute to the current presentation, necessitating an analysis of acceleration or exacerbation rather than simple causation.

Distinguishing causation from quantum in the evidential base

In England and Wales, where expert evidence is governed by CPR Part 35, the report must clearly distinguish between facts established by the records and opinions formed during the examination. Causation in RTA claims requires the application of the ‘but-for’ test: would the injury have occurred but for the accident? The medical evidence provides the clinical foundation for this analysis, but the expert must remain within the limits of their discipline.

• Ensure the expert does not attempt to interpret traffic collision reports, which are the remit of accident reconstruction specialists.
• Recognise that the expert must identify when a condition involves psychiatric or psychological elements that exceed their clinical expertise.
• Note that psychiatric or psychological elements may require the instruction of a separate expert under CPR Part 35.

Where an expert attempts to reach a conclusion on matters outside their clinical discipline, the evidence risks being excluded for exceeding the expert’s remit. The handover between disciplines is essential for ensuring that each head of loss is addressed by the appropriate specialist.

Expert duties and the resolution of disputed evidence

Under CPR 35.3, an expert’s overriding duty is to the court, which remains the same regardless of whether the expert has performed a records review or an IME. When two experts hold conflicting views on causation, the court may direct a discussion and the production of a joint statement under CPR 35.12. This process is intended to narrow the issues. It is not an opportunity for parties to re-litigate the claim or pressure the expert to deviate from their clinical opinion.

The decision to proceed with a records review or a full examination directly affects the cost-proportionality of the expert evidence. In some circumstances, the court may direct that evidence be given by a single joint expert under CPR 35.7, with instructions provided to that expert under CPR 35.8. An IME is rarely required where the medical records provide a clear and uncontested account of the injury, and an unnecessary examination may be scrutinised during the assessment of costs.