Studies were synthesised qualitatively and grouped into categories addressing the following questions:
1. Does providing nutritional support, compared to no nutritional support, make a difference in patient outcomes?
2. What is the effect of EN compared to TPN with respect to infectious outcomes?
3. How does timing of administration of EN affect infectious morbidity and mortality of critically ill patients?
4. What is the preferred method of delivering EN?
5. Does the composition of EN affect the infectious morbidity and mortality in critically ill patients?