Table 2. Summary of all included studies.
| Study Publication year | Quality points | Number (n) colonoscopies | Study type | Bowel preparation scale |
|---|---|---|---|---|
| Mahadev [1] 2014 | 4 | 1,649 | Comparative Retrospective | Unique |
| Kim [28] 2014 | 5 | 482 | Comparative Prospective | BBPS Aronchick |
| Holt [19] 2014 | 4 | 413 | Comparative Prospective | Ottawa |
| Singhal [23] 2014 | 1 | 297 | Repeat-colonoscopy Retrospective | Aronchick |
| Anderson [25] 2014 | 1 | 13,022 | Comparative Prospective | Unique |
| Lee [41] 2014 | 4 | 31,088 | Comparative Prospective | Unique |
| Fayad [42] 2013 | 2 | 2,163 | Comparative Retrospective | Aronchick |
| Menees [31] 2013 | 3 | 71 | Repeat-colonoscopy Retrospective | Aronchick |
| Gao [37] 2013 | 4 | 1,012 | Comparative Prospective | BBPS |
| Jover [26] 2013 | 6 | 4,539 | Comparative Prospective (RCT) | Aronchick |
| Bryant [27] 2012 | 0 | 1,785 | Comparative Retrospective | Unique |
| Adler [43] 2013 | 6 | 11,166 | Comparative Prospective | Aronchick-based |
| Chokshi [29] 2012 | 3 | 133 | Repeat-colonoscopy Retrospective | Aronchick |
| Goncalves [44] 2011 | 2 | 1,545 | Comparative Retrospective | Unique |
| Sherer [45] 2012 | 2 | 8,800 | Comparative Retrospective | Unique |
| De Jonge [39] 2012 | 2 | 4,800 | Comparative Retrospective | Unique |
| Enestvedt [46] 2011 | 4 | 190 | Comparative Prospective (RCT) | BBPS |
| Calderwood [33] 2010 | 4 | 983 | Comparative Prospective | BBPS |
| Shaukat [47] 2009 | 5 | 47,253 | Comparative Retrospective | Unique |
| Radaelli [48] 2008 | 1 | 12,835 | Comparative Consecutive | Unique |
| Froehlich [22] 2005 | 2 | 5,832 | Comparative Prospective | Unique |
| Harewood [13] 2003 | 1 | 93,004 | Comparative Retrospective | Unique |
| Pontone [49] 2014 | 1 | 190 | Comparative Retrospective | Aronchick |
| Xiang [30] 2014 | 3 | 2,093 | Repeat-colonoscopy Retrospective | Unique |
| Aslanian [50] 2013 | 4 | 502 | Comparative Prospective (RCT) | Aronchick |
| Lebwohl [12] 2011 | 1 | 216 | Repeat-colonoscopy Retrospective | Aronchick |
| Hong [21] 2012 | 5 | 277 | Repeat-colonoscopy Prospective | Aronchick |
Quality points were given for a detailed reporting of lesions, the study population, study design, validation of stool scales and correction for confounders (for details see methods). RCT: Randomized controlled trial. BBPS: Boston Bowel Preparation Scale.