| Helmer (2002) | Pediatric & adult | 438 | X | X | X |
| Dubois (2010) | Adult | 317 | X | X | X |
| Zinaman (2003) | Adult | 42 | X | X |
|
| Keller (1996) | Pediatric/complicated appendicitis | 56 | X | X | X |
| Firilas (1999) | Pediatric | 147 | X | X | X |
| Adibe (2011) | Pediatric | 311 | X |
|
|
| Knott (2013) | Pediatric/PA | 209 | X |
| X |
| Putnam (2014) | Pediatric | 794 |
| X | X |
| Akkoyun (2013) | Pediatric | 129 | X | X | X |
| Hussain (2014) | Adult | 30 |
| X |
|
| Almonda (2008) | Pediatric | 429 | X | X | X |
| Antevil (2006) | Adult | 992 | X |
|
|
| Smink (2004) | Pediatric | 959 | X |
|
|
| Garcia Pena (2002) | Pediatric | 1338 | X |
|
|
| Krishnamoorthi (2011) | Pediatric | 631 | X |
|
|
| Santillanes (2012) | Pediatric | 475 | X |
|
|
| Naoum (2002) | Adult | 194 | X |
|
|
| Yu (2014) | Pediatric/complicated appendicitis | 94 | X |
|
|
| Torbati (2003) | Adult & pediatric | 506 | X |
| X |
| Ball (2014) | Adult | 741 | X |
|
|
| Skarda (2014) | Pediatric/ruptured appendicitis | 306 | X | X |
|
| Bensard (2009) | Pediatric | 72 |
| X |
|