Terms and Synonyms Searched:
| Terms | Search Results* | Entire Database** |
|---|---|---|
| Synonyms | ||
| vaccine, phase 4 | -- | 0 studies |
| phase 4 | 107 studies | 31,516 studies |
| phase iv | 24 studies | 1,826 studies |
| fourth phase | -- | 8 studies |
| phase four | -- | 15 studies |
| phase | 296 studies | 218,830 studies |
| Stage | 16 studies | 35,433 studies |
| Phased | -- | 215 studies |
| vaccine | 296 studies | 11,095 studies |
| Covid19 | 296 studies | 9,070 studies |
| SARS-CoV-2 infection | 40 studies | 787 studies |
| Coronavirus disease 2019 | 14 studies | 405 studies |
| Coronavirus Disease 19 | 2 studies | 57 studies |
| SARS-CoV-2 Disease | 1 studies | 13 studies |
| Severe Acute Respiratory Syndrome Coronavirus 2 Infection | 1 studies | 10 studies |
| 2019 nCoV Disease | -- | 6 studies |
| 2019 nCoV Infection | -- | 10 studies |
| 2019 Novel Coronavirus Disease | -- | 21 studies |
| 2019 Novel Coronavirus Infection | -- | 16 studies |
| coronavirus 2019-nCoV | -- | 1 studies |
| Disease caused by 2019-nCoV | -- | 1 studies |
| Disease caused by SARS-CoV-2 | -- | 5 studies |
| SARS Coronavirus 2 Infection | -- | 5 studies |
| -- | No studies found |
| * | Number of studies in the search results containing the term or synonym |
| ** | Number of studies in the entire database containing the term or synonym |