1. What do the terms "duty of care", "breach of duty" and "causation" mean?

Duty of care

The concept of duty of care comes from a well-known British case (Donoghue v Stevenson) in which it was pointed that everyone should take reasonable care to avoid acts or omissions that are likely to injure their neighbours. The word 'neighbour' in this sense does not simply refer to the person living next door, but includes any persons who are likely to be affected by your activities. In this regard, doctors and other medical practitioners normally owe a duty of care to their patients when they are administering medical treatment.

However, doctors are not obliged to achieve success with every case that they treat. The duty of doctors is to exercise reasonable skill and care towards each patient when administering medical treatment (see question 2). Generally speaking, doctors are not deemed to be negligent if they act in accordance with a practice that is accepted as proper by a responsible body of medical opinion, even though a different practice may be adopted by other doctors to treat the same disease or injury.

Breach of duty

If a doctor does not follow the usual practice without good reason and this results in injury to a patient, then it is likely that the doctor has breached the duty of care and will be found to have been negligent.

The following three elements must be established in determining a breach of duty:

1. There is a usual and normal practice (as justified by precedent cases or approved by recognised medical bodies) for conducting the medical treatment in question.
2. The doctor responsible did not adopt that practice.
3. The practice that the doctor adopted is one that no person in that profession with ordinary skill would have used if they had been acting with ordinary care (examples include a doctor ignoring an important step in the treatment, or applying treatment in a way that no other reasonable doctor would have done).

However, you should note that in many instances of medical treatment or operation there is no uniform "general and approved practice". Rather, there may be different respectable schools of thought on the treatment that can be administered for a particular kind of decease or injury. If a doctor acts in accordance with one of these schools of thought, then that doctor is unlikely to be found liable for negligence merely because there is a body of opinion that would take a contrary view (i.e. that would adopt another medical treatment for the same decease or injury).

A defending doctor's approach to diagnosis, advice and treatment should stand up to logical analysis, and should be reasonable in the light of the state of medical knowledge at the time. After considering all of the evidence, including explanations of relevant medical reports, it is ultimately for the Court, rather than medical experts, to determine whether the defendant is liable for medical negligence.

Causation (the damage was caused by the breach of duty)

(a) The "but for" test

The patients must prove that but for (without) the negligence, they would not have suffered the injury for which they are claiming.

Example:
A patient was sent to the accident and emergency department of a hospital, but there was a delay in giving the patient proper medical treatment. However, the patient was already in a very poor state when he arrived at the hospital and nothing could have been done to save him. In these circumstances, medical negligence may not be established, as no possible medical treatment could have saved the patient. "But for" the medical incident, he would have died even if he had been given the best possible medical treatment without any delay.

(b) Material or significant contribution to the injury

When there are multiple causes for a patient's medical condition in addition to the alleged negligence of the doctor (that is, more than one factor contributed to the patient's injury or illness), then the patient's claim for medical negligence will only succeed and may result in full compensation if the alleged negligence of the doctor can be proven to have materially contributed to the injury suffered by that patient.

Example:
A patient was sent to the accident and emergency department of a hospital, but there was a delay in giving him proper medical treatment and he died. He was already in a very poor state when he arrived at the hospital, but had he received the proper medical treatment without any delay, he could have been saved. In these circumstances, medical negligence may be established (and the patient's family may be entitled to full compensation) if it can be proved that the alleged negligence of the doctor (the delay in giving treatment) significantly contributed to the patient's death.