The timing of bowel preparation before colonoscopy determines the quality of cleansing, and is a significant factor contributing to the detection of flat lesions: A randomized study

Table 3 Distribution by size and shape of all polyps detected in the patients who received bowel preparation the same day and the day before

Lesion	Preparationsame day(group 1, 2)	Preparationday before(group 3, 4)	P
Polyp size (mean ± SD)	5.6 ± 3.8	5.3 ± 5.1	NS
Polyp size ≤ 5 mm (n = 121)	59	62	NS
Flat lesions (n = 37)	28	9	< 0.01
Flat lesions size (mean ± SD)	4.8 ± 3.7	9.0 ± 12.0	NS
Protruding polyps (n = 146)	69	77	NS
Protruding polyps size (mean ± SD)	5.9 ± 3.8	4.9 ± 3.6	NS
Total polyps (flat + protruding) (n = 183)	97	86	NS

Bonferroni's correction.