Estimated difference or ratio | ||||||||
---|---|---|---|---|---|---|---|---|
PF | SBP | Pain | ||||||
Test | Needle 1 | Needle 2 | Ratio | p Value | Ratio | p Value | Difference (mm) | p Value |
Diameter | NF-32 | NF30 | 1.16* | <0.01 | 1.04 | 0.72 | 0.44 | 0.90 |
NF-32 | NF28 | 1.29* | <0.01 | 1.51* | <0.01 | 4.58 | 0.20 | |
NF-30 | NF28 | 1.11* | <0.05 | 1.45* | <0.01 | 4.13 | 0.25 | |
Tip design | ||||||||
Asymmetrical 3-grind | NF-32 | TER-34 | 0.71* | <0.01 | 0.97 | 0.85 | −1.28 | 0.72 |
BD-32 | TER-34 | 1.08 | 0.06 | 0.83 | 0.11 | 0.28 | 0.94 | |
3-grind vs 5-grind | NF-32 | BD-32 | 0.66* | <0.01 | 1.17 | 0.16 | −1.56 | 0.66 |
Standard 3-grind vs short 3-grind | HN-32 | HN3-32 | 2.18* | <0.01 | 1.60* | <0.01 | 6.71 | 0.067 |
HN-32 | HN3-34 | 1.34* | <0.01 | 1.28* | 0.03 | 4.14 | 0.26 | |
HN3-32 | HN3-34 | 0.62* | <0.01 | 0.80 | 0.05 | −2.58 | 0.48 | |
Standard 3-grind vs short 2-grind | HN-32 | HN2-32 | 3.00* | <0.01 | 1.75* | <0.01 | 11.97* | <0.01 |
HN-32 | HN2-34 | 1.80* | <0.01 | 1.41* | <0.01 | 6.58 | 0.09 | |
HN2-32 | HN2-34 | 0.60* | <0.01 | 0.81 | 0.10 | −5.39 | 0.20 | |
Standard 3-grind vs short 1-grind | HN-32 | HN1LO-32 | 1.34* | <0.01 | 1.42* | <0.01 | 2.17 | 0.55 |
HN-32 | HN1LO-34 | 1.33* | <0.01 | 1.15 | 0.22 | −1.72 | 0.64 | |
HN1LO-32 | HN1LO-34 | 0.99 | 0.89 | 0.81 | 0.082 | −3.89 | 0.29 | |
HN-32 | HN1SH-32 | 2.14* | <0.01 | 1.74* | <0.01 | 6.77 | 0.07 | |
HN-32 | HN1SH-34 | 1.59* | <0.01 | 1.26* | 0.04 | 5.28 | 0.15 | |
HN1SH-32 | HN1SH-34 | 0.74* | <0.01 | 0.72* | <0.01 | −1.49 | 0.69 | |
Worn-off silicone | NF-32 | NOSILIC | 1.51* | <0.01 | 1.30* | <0.05 | 0.137 | 0.96 |
Hooks | NF-32G | HOOK50 | 1.94* | <0.01 | 1.38* | <0.01 | 3.54 | 0.33 |
NF-32G | HOOK150 | 5.55* | <0.05 | 2.48* | <0.01 | 12.45* | <0.01 | |
HOOK50 | HOOK150 | 2.86* | <0.01 | 1.79* | <0.01 | 8.91* | <0.05 |
Between-needle comparisons of peak PF and increase of SBP, respectively, are expressed as a ratio. A ratio value higher than 1.00 indicates that needle 2 caused higher PF or SB than needle 1. Pain comparisons are expressed as a difference in mm on a 100 mm VAS scale. A positive value indicates that needle 2 rated higher on pain than needle 1.
*Comparison is statistically different (p<0.05).
PF, penetration force; SBP, skin blood perfusion; VAS, visual analog scale.