Mays v Drive Force (UK) Ltd

In an appropriate personal injury claim, statistical evidence on life expectancy may be admitted alongside clinical evidence. The court is not confined to evidence from clinicians where statistical or other expert input may assist with factors affecting lifespan, including co-morbid conditions. The evidence should be assessed as part of an interdisciplinary approach. Its ultimate usefulness, credibility and weight remain matters for the trial judge. Permission is more readily justified where the claim is substantial, the issue may materially affect quantum, and the existing clinical experts cannot address all relevant factors. Such evidence remains subject to proportionality and does not establish a general requirement for a separate life expectancy expert in every case.

The claimant suffered catastrophic brain and orthopaedic injuries in a workplace accident. Liability was admitted. At a costs and case management conference, the parties agreed permission for several experts, but disagreed about whether each should also rely on expert evidence concerning life expectancy.

The defendant relied on statistical evidence addressing smoking, hypertension, obesity and ulcerative colitis. The claimant argued that life expectancy was ordinarily a clinical matter and that separate statistical evidence would be disproportionate and potentially lead to routine instruction of such experts. The issue was whether permission should be granted for the proposed evidence.

The application was granted. Both parties were given permission to rely on expert life expectancy evidence.

1. The authorities established that factors other than the index event may affect life expectancy and that the court may be assisted by expert evidence addressing them. Statistical evidence is not necessarily inadmissible merely because it is derived from a statistical database rather than clinical examination.
2. Royal Victoria Infirmary and Associated Hospitals NHS Trust v B (a child) [2002] PIQR Q10 supported an interdisciplinary approach. Statistical evidence may provide a useful starting point when considered together with medical evidence. Courts are not confined to clinicians alone.
3. Lewis v Royal Shrewsbury Hospital NHS Trust [2007] 1 WLUK 628 illustrated that statistical evidence may be highly relevant and provide a guide to likely survival, subject to scrutiny of its limitations.
4. Wolstenholme v Leach’s of Shudehill Ltd [2016] EWHC 588 (QB) showed that such evidence may be admitted even though the trial judge may ultimately prefer competing clinical evidence.
5. In this case, the number of potential co-morbid factors, the inability of the instructed neurologists to address all of them, the substantial value of the claim and the potential effect on future loss made the evidence capable of assisting the trial judge. The additional expertise was proportionate. Questions concerning reliability, credibility and ultimate weight were reserved for trial.