1. Interventions by medical specialty.
| Medical speciality | Experimental group | Control group |
| Emergency medicine | 3 trials used enteral nutrition 8 trials used parenteral nutrition |
7 trials used no intervention 4 trials used treatment as usual |
| Endocrinology | 1 trial used parenteral nutrition | 1 trial used no intervention |
| Gastroenterological surgery | 36 trials used enteral nutrition 13 trials used oral nutrition 40 trials used parenteral nutrition 3 trials used mixed nutrition |
32 trials used no intervention 4 trials used placebo 56 trials used treatment as usual |
| General surgery | 2 trials used parenteral nutrition | 1 trial used no intervention 1 trial used treatment as usual |
| Geriatrics | 1 trial used fortified foods 2 trials used general nutrition support 13 trials used oral nutrition |
9 trials used no intervention 2 trials used placebo 5 trials used treatment as usual |
| Gynaecology | 1 trial used parenteral nutrition | 1 trial used treatment as usual |
| Haematology | 1 trial used parenteral nutrition | 1 trial used placebo |
| Infectious diseases | 2 trials used enteral nutrition | 2 trials used treatment as usual |
| Medical gastroenterology and hepatology | 9 trials used enteral nutrition 3 trials used oral nutrition 5 trials used parenteral nutrition 1 trial used mixed nutrition |
9 trials used no intervention 9 trials used treatment as usual |
| Mixed medical speciality | 2 trials used enteral nutrition 1 trial used fortified foods 1 trial used general nutrition 4 trials used oral nutrition 1 trial used mixed nutrition |
5 trials used no intervention 1 trial used placebo 3 trials used treatment as usual |
| Neprohology | 1 trial used general nutrition | 1 trial used treatment as usual |
| Neurological surgery | 1 trial used parenteral nutrition | 1 trial used treatment as usual |
| Neurology | 3 trials used enteral nutrition 1 trial used general nutrition 5 trials used oral nutrition 1 trial used mixed nutrition |
4 trials used no intervention 6 trials used treatment as usual |
| Oncology | 3 trials used enteral nutrition 1 trial used general nutrition 11 trials used parenteral nutrition 1 trial used mixed nutrition |
9 trials used no intervention 7 trials used treatment as usual |
| Oro‐maxillo‐facial surgery | 1 trial used enteral nutrition 1 trial used oral nutrition |
2 trials used no intervention |
| Orthopaedics | 5 trials used enteral nutrition 4 trials used oral nutrition 1 trial used general nutrition 1 trial used parenteral nutrition 3 trials used mixed nutrition |
7 trials used no intervention 2 trials used placebo 5 trials used treatment as usual |
| Pulmonary diseases | 2 trials used enteral nutrition 3 trials used oral nutrition 3 trials used parenteral nutrition |
1 trial used no intervention 3 trials used placebo 4 trials used treatment as usual |
| Thoracic surgery | 2 enteral nutrition 1 parenteral nutrition 1 mixed nutrition |
1 trial used placebo 3 trials used treatment as usual |
| Trauma surgery | 8 trials used enteral nutrition 3 trials used parenteral nutrition |
6 trial used no intervention 5 trial used treatment as usual |
| Transplant surgery | 1 trial used enteral nutrition 1 trial used oral nutrition 2 trials used parenteral nutrition |
4 trials used treatment as usual |
| Vascular surgery | 1 trial used enteral nutrition 3 trials used parenteral nutrition |
4 trials used treatment as usual |