Medical negligence requires the plaintiff (i.e. the patient or relative if the patient has died) should establish the following 4Ds: 

1. Existence of the doctor’s Duty to the plaintiff based on existence of the doctor-patient relationship. 
2. Applicable standard of care and its violation (Dereliction of Duty). 
3. Direct causation (failure to exercise a duty of care must lead to damage) 
4. Damage (a compensable injury).