Table 2.

Studied needles’ average rank and incidence-rate ratios (IRRs)

	Pooled		Overall		TED		SED
Needle	Avg. Rank (95% CI)	IRR	Avg. Rank (95% CI)	IRR	Avg. Rank (95% CI)	IRR	Avg. Rank (95% CI)	IRR
5	8.63 (8.07, 9.19)	-ref-	8.82 (8.39–9.24)	-ref-	8.40 (7.94–8.86)	-ref-	8.72 (8.36, 9.07)	-ref-
10	7.72 (7.20, 8.24)	0.89 p=0.004 (0.83, 0.97)	7.92 (7.44–8.41)	0.90 p=0.001 (0.84, 0.96)	7.51 (7.02–7.99)	0.89 p=0.007 (0.82, 0.97)	7.76 (7.31, 8.20)	0.89 p<0.001 (0.84, 0.94)
1	7.27 (6.77, 7.77)	0.84 p<0.001 (0.78, 0.91)	7.27 (6.79–7.74)	0.82 p<0.001 (0.76, 0.89)	7.17 (6.76–7.58)	0.85 p<0.001 (0.79, 0.92)	7.34 (6.93, 7.76)	0.84 p<0.001 (0.80, 0.89)
6	7.23 (6.73, 7.72)	0.84 p<0.001 (0.77, 0.90)	7.53 (7.03–8.03)	0.85 p<0.001 (0.80, 0.92)	6.16 (5.67–6.66)	0.73 p<0.001 (0.67, 0.80)	8.00 (7.63, 8.38)	0.92 p=0.001 (0.87, 0.97)
8	6.92 (6.44, 7.40)	0.80 p<0.001 (0.74, 0.87)	7.13 (6.62–7.64)	0.81 p<0.001 (0.74, 0.88)	6.09 (5.57–6.60)	0.72 p<0.001 (0.66, 0.80)	7.53 (7.11, 7.95)	0.86 p<0.001 (0.81, 0.92)
7	6.91 (6.42, 7.39)	0.80 p<0.001 (0.74, 0.87)	7.07 (6.68–7.47)	0.80 p<0.001 (0.76, 0.85)	6.30 (5.86–6.74)	0.75 p<0.001 (0.69, 0.81)	7.33 (6.96, 7.71)	0.84 p<0.001 (0.80, 0.89)
2	6.69 (6.21, 7.16)	0.77 p<0.001 (0.72, 0.84)	7.21 (6.65–7.77)	0.82 p<0.001 (0.75, 0.90)	5.94 (5.48–6.41)	0.71 p<0.001 (0.64, 0.78)	6.98 (6.44, 7.52)	0.80 p<0.001 (0.73, 0.87)
9	6.29 (5.83, 6.74)	0.73 p<0.001 (0.67, 0.79)	6.57 (5.98–7.17)	0.75 p<0.001 (0.67, 0.82)	5.35 (4.81–5.89)	0.64 p<0.001 (0.57, 0.71)	6.93 (6.48, 7.38)	0.80 p<0.001 (0.75, 0.85)
3	6.04 (5.60, 6.48)	0.70 p<0.001 (0.64, 0.76)	6.47 (5.94–7.00)	0.73 p<0.001 (0.67, 0.80)	4.74 (4.27–5.21)	0.56 p<0.001 (0.50, 0.63)	6.96 (6.57, 7.36)	0.80 p<0.001 (0.75, 0.85)
4	5.05 (4.65, 5.45)	0.58 p<0.001 (0.54, 0.64)	5.02 (4.42–5.63)	0.57 p<0.001 (0.50, 0.65)	4.72 (4.22–5.21)	0.56 p<0.001 (0.50, 0.64)	5.31 (4.77, 5.85)	0.61 p<0.001 (0.55, 0.68)

^*Needles were sorted in descending order based on the pooled average rank.

TED: tip echo-definition, SED: shaft echo-definition, Avg.: average.