| Abbreviation | Definition |
|---|---|
| SHTAC | This was a Special Health Board established in 2000, and as far as I can tell, rolled into the Health Technology Board for ScotlandHTBS, which in turn has also been shuttered |
| SHTAC | This was a Special Health Board established in 2000, and as far as I can tell, rolled into the Health Technology Board for Scotland–HTBS, which in turn has also been shuttered |
| SI | sagittal index |
| SI | saline infusion |
| SI | satiety index |
| SI | self-inflicted |
| SI | sensitivity index |
| SI | serious illness |
| SI | serious injury |
| SI | seriously ill |
| SI | serum iron |
| SI | severity index |
| SI | sexual intercourse |
| SI | sexually inexperienced |
| SI | shock index |
| SI | signal intensity |
| SI | silent infarction |
| SI | silent ischaemia |
| SI | silver |
| SI | Singh Index |