## Facts

- The claimant, a young boy, sustained a fractured hip after falling from a tree.
- Medical staff at the defendant hospital failed to diagnose the fracture at his initial visit, sending him home without treatment.
- Five days later, upon re-admission due to persistent pain, the fracture was detected, but the claimant had already developed avascular necrosis.
- This condition resulted in permanent disability and increased the likelihood of future osteoarthritis.
- Expert testimony indicated that if treated promptly, there was a 25% chance of preventing the onset of avascular necrosis.
- The trial judge awarded the claimant 25% of full damages, reflecting this probability.

## Issues

1. Whether damages can be awarded for the “loss of a chance” of a better medical outcome due to a defendant’s negligence.
2. Whether the claimant established, on the balance of probabilities, that the hospital’s negligence caused his injury.

## Decision

- The House of Lords reversed the lower court’s award and ruled in favour of the East Berkshire Area Health Authority.
- The Court held that to establish causation in negligence, the claimant must prove it was more likely than not (over 50%) that the defendant’s breach caused the injury.
- The Court found that the avascular necrosis likely resulted from the original injury, not the negligent delay, and that prompt treatment would have changed the outcome only in 25% of cases.
- Therefore, the claimant could not recover damages as he failed to prove causation on the balance of probabilities.
- The Court confirmed that “loss of a chance” is not compensable in medical negligence unless actual injury is proven to have been caused by the negligence.

## Legal Principles

- In negligence, a claimant must prove causation on the balance of probabilities; a mere chance of a better outcome is not compensable.
- “Loss of a chance” claims in medical negligence are not actionable where the probability of avoiding harm is less than 50%.
- The assessment of causation in tort differs from contract law cases such as _Chaplin v Hicks_, where loss of opportunity may be recoverable.
- When liability is established on the balance of probabilities, full damages are payable; partial awards based on statistical chance are not permitted in negligence.

## Conclusion

The House of Lords in Hotson v East Berkshire Area Health Authority established that claimants in medical negligence must prove, on the balance of probabilities, that the defendant’s breach caused their injury; loss of a chance is not itself a compensable injury in tort. This strict standard remains authoritative in English negligence law.


Hotson v East Berkshire Area Health Authority [1987] AC 750 (HL)