Can optical diagnosis of small colon polyps be accurate? Comparing standard scope without narrow banding to high definition scope with narrow banding

Table 1 Comparing the characteristics of patients underwent standard scope vs high definition scope with narrow band imaging n (%)

Parameters	Standard scope (1) (n = 68)	HD scope (n = 72)	P value
Female	41 (60)	48 (67)	0.40
Age (yr), median (IQR)	56 (52-61)	57 (53-64)	0.70
Education			0.40
High school and lower	31 (46)	38 (54)
> High school	37 (54)	34 (47)
H/o previous colonoscopy	25 (37)	19 (26)	0.20
H/o previous colon polyp	6 (9)	7 (10)	0.80
Family h/o colon cancer	22 (22)	12 (17)	0.40
Indication			0.20
Screening	34 (50)	45 (63)
Diagnostic	18 (26)	19 (26)
Follow up	16 (24)	8 (11)
Colon preparation			0.08
Good	63 (93)	71 (99)
Moderate	5 (7)	1 (1)
Number of patient with polyp diagnosis	41 (60)	49 (68)	0.30
Total number of polyps detected, median (IQR)	1 (1-2)1	2 (1-3)2	0.20
Adenoma detection rate	23 (34)	32 (44)	0.20
Advanced adenoma detection rate	7 (10)	8 (11)	0.90
Hyperplastic polyp detection rate	19 (28)	21 (29)	0.90
Proportion of patients with multiple polyps	17 (41)1	28 (57)2	0.10

¹n = 41;

²n = 49. HD: High definition.

Table 2 Clinical diagnostic value of adenoma by scope

	Sensitivity (%)	Specificity (%)	PPV (%)(true positive/all positive)	NPV (%)(true negative/all negative)	PLR (%)(true positive/false positive)
ALL	61 (51-70)	79 (69-86)	78 (68-86)	62 (53-71)	2.9 (1.8-4.5)
Scope 1	53 (39-67)	87 (70-95)	86 (69-94)	55 (41-69)	4.0 (1.5-10.4)
Scope 2	68 (55-79)	74 (60-84)	74 (60-84)	69 (55-79)	2.6 (1.6-4.3)
P value for two scopes	0.1	0.2	0.2	0.1

Numbers in parentheses indicate 95%CI. PPV: Positive predictive value; NPV: Negative predictive value; PLR: Positive likelihood ratio.

Table 3 Clinical diagnostic value of hyper plastic polyp by scope

	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	PLR (%)
All	73 (59-84)	63 (55-71)	40 (30-51)	88 (79-93)	2.0 (1.5-2.6)
Scope 1	74 (51-88)	59 (46-71)	38 (24-54)	87 (73-94)	1.8 (1.2-2.7)
Scope 2	74 (54-86)	66 (55-76)	42 (29-57)	88 (77-94)	2.2 (1.5-3.2)
P value for two scopes	0.9	0.4	0.7	0.9

Numbers in parentheses indicate 95%CI. PPV: Positive predictive value; NPV: Negative predictive value; PLR: Positive likelihood ratio.

Table 4 Comparison of clinical characteristics of all polyps in standard scope vs high definition scope with narrow band imaging n (%)

Parameters	Standard scope (1) (n = 75)	HD scope (2) (n = 103)	P value
Polyps < 10 mm in size	67 (89)	89 (87)	0.7
Adenoma detection rate	45 (60)	53 (51)	0.3
Hyperplastic polyp detection rate	19 (25)	26 (25)	0.9

HD: High definition.

Table 5 Comparasion of adenoma detection between endoscopists

Parameter	Sensitivity	Specificity	PPV	NPV	PLR
Endoscopist 1	75 (55-88)	88 (70-96)	86 (65-95)	79 (61-90)	6.3 (2.1-18.5)
Endoscopist 2	60 (46-74)	78 (58-90)	84 (67-93)	51 (34-67)	2.8 (1.2-6.3)
Endoscopist 3	52 (35-68)	72 (55-84)	64 (45-80)	61 (45-74)	1.8 (0.4-1.0)
P value for three endoscopists	0.2	0.3	0.1	0.1

PPV: Positive predictive value; NPV: Negative predictive value; PLR: Positive likelihood ratio.

Table 6 Comparison of hyper plastic polyp detection between endoscopists

Parameter	Sensitivity	Specificity	PPV	NPV	PLR
Endoscopist 1	53 (32-73)	83 (66-93)	67 (42-85)	74 (57-85)	3.2 (1.3-7.8)
Endoscopist 2	91 (62-98)	56 (43-69)	29 (17-46)	97 (84-99)	2.1 (1.5-3.0)
Endoscopist 3	87 (62-96)	58 (44-71)	39 (25-56)	93 (79-98)	2.1 (1.4-3.1)
P value for three endoscopists	0.026	0.033	0.049	0.008

PPV: Positive predictive value; NPV: Negative predictive value; PLR: Positive likelihood ratio.