Table 4. Effects of bowel preparation on the detection of right-sided, flat or serrated polyps/ adenomas.
| Study Year of publication | Quality | n | Readout | Study results | Study conclusion |
|---|---|---|---|---|---|
| Comparative studies | |||||
| Kim [28] 2014 | 5 | 482 | Right- sided polyps | Correlation analysis: BBPS≥ 8 vs. BBPS< 8 BBPS segment scores in the right colon but not in the left colon correlated with polyp detection rates (right: r = 0.107, p = 0.018; left: r = 0.059, p = 0.198) | Bowel preparation more relevant for polyp detection in the right colon |
| de Wijkerslooth [24] 2013 | 6 | 1,354 | Proximal serrated adenoma | Multivariate analysis: Ottawa scale was associated with: | Bowel preparation equally relevant for detection of right-sided serrated adenoma vs. other adenomas |
| - overall ADR (OR 0.95; CI: 0.91–0.99) | |||||
| - but not proximal SDR (OR: 0.98; CI: 0.92–1.05) | |||||
| Anderson [25] 2014 | 1 | 13,022 | Right- sided serrated | Optimal vs. poor bowel preparation | Bowel preparation equally relevant for overall, right-sided, and serrated adenoma detection |
| - Overall ADR: 26.3% vs. 20.9% | |||||
| - Proximal ADR: 12.9% vs. 8% | |||||
| - SDR 8.8% vs. 7.5% | |||||
| no significant differences | |||||
| Lee [41] 2014 | 4 | 31,088 | Right-sided | Adequate vs. inadequate bowel preparation | Bowel preparation equally relevant for adenoma detection in the right and left colon |
| - OR overall adenoma detection 1.38 (1.23–1.54) | |||||
| - OR right sided adenoma 1.16 (1.13–1.33) | |||||
| no significant differences | |||||
| Jover [26] 2013 | 6 | 4,539 | Right-sided | No significant effects of bowel preparation on adenoma detection, similar trends for right- and left sided adenomas | Bowel preparation equally relevant for adenoma detection in the right and left colon |
| Bryant [27] 2012 | 0 | 1785 | Right- sided polyp | Adequate vs. poor preparation | Bowel preparation equally relevant for polyp detection in the right and left colon |
| - OR left-side: 1.1 (0.8–1.5) | |||||
| - OR right-side: 1.1 (0.8–1.5) | |||||
| no significant differences | |||||
| Calderwood [33] 2010 | 4 | 983 | Right-sided polyp | BBPS 0.1 vs. BBPS 2,3. Multivariate analysis | Bowel preparation equally relevant for polyp detection in the right and left colon |
| - OR right side: 1.6 (1.01–2.55) | |||||
| - OR left side: 2.6 (1.34–4.98) | |||||
| Repeat colonoscopy studies | |||||
| Xiang [30] 2014 | 3 | 2,093 | Flat adenoma | In patients with poor bowel preparation the OR for missing a flat adenoma is 4.4 (no comparison to protruding adenoma provided) | Bowel preparation relevant for flat adenoma miss rate |
| Lebwohl [12] 2011 | 1 | 216 | Proximal | Adenoma miss rate 42% for proximal and distal adenomas | Bowel preparation equally relevant for adenoma miss rate in the right and left colon |
| Singhal [23] 2014 | 1 | 297 | Right-sided | 67% of all missed adenomas were right-sided adenomas | Bowel preparation more relevant for adenoma miss rate in the right colon |
| Chokshi [29] 2012 | 3 | 133 | Right-sided | 65% of all missed adenomas and 80% of all missed advanced adenomas were in the right colon | Bowel preparation more relevant for adenoma miss rate in the right colon |
n.s. = not significant. ADR = Adenoma detection rate. Adv. ADR = Advanced adenoma detection rate. SDR = serrated adenoma detection rate. BBPS = Boston Bowel Preparation Scale.