Shortened eutectic mixture of lidocaine and prilocaine plus skin cooling for pediatric vaccination pain: A randomized non-inferiority trial

Table 2 Wong-Baker FACES Pain Rating Scale scores and non-inferiority analysis at each assessment time point (linear mixed-effects model, intention-to-treat population, n = 150), mean ± SD

Time point	Group A	Group B	Adjusted difference (B-A)	95%CI	Non-inferiority
Before injection	0.89 ± 1.37	0.95 ± 2.08	+0.07	-0.70 to +0.80	Met
Immediately after injection (primary)	2.73 ± 2.66	2.42 ± 3.03	-0.30	-1.00 to +0.50	Met
5 minutes after injection	2.00 ± 2.20	1.76 ± 2.29	-0.22	-1.00 to +0.50	Met

Adjusted mean differences are presented as group B minus group A; because lower Wong-Baker FACES scores indicate less pain, negative values favour group B. Non-inferiority was concluded if the upper bound of the two-sided 95% confidence interval lay below the prespecified margin of Δ = +1.4 points (equivalent to a one-sided α of 0.025). The model included a random intercept per participant and fixed effects for group, time point and their interaction. CI: Confidence interval.