| Abbreviation | Definition |
|---|---|
| CRO | Clinical Research Organization |
| CRO | Contract Research Organization |
| CRP | C-Reactive Protein |
| CRR | Consult Review Request |
| CRS | Congressional Research Service |
| CRS | Contamination Response System |
| CRT | Case Report Tabulation |
| CRTP | Clinical Research Training Program |
| CRU | Center Recall Unit |
| CRWG | Hurricane Katrina Comprehensive Review Working Group |
| CS | Civil Service |
| CS | Clinically Significant |
| CS(CVM) | Communications Staff (CVM) |
| CS(OC) | Communications Staff (OC) |
| CSA | Clinical Study Agreement |
| CSA | Controlled Substances Act |
| CSAP | Center for Substance Abuse Prevention (SAMHSA) |
| CSAT | Center for Substance Abuse Treatment |
| CSAT | Center for Substance Abuse Treatment (SAMHSA) |
| CSB | Chemical Safety and Hazard Investigation Board |