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

Figure 1 Consolidated Standards of Reporting Trials flow diagram showing participant enrollment, allocation, follow-up, and analysis. A total of 150 children were recruited and randomized into two groups: 74 were allocated to group A and received a eutectic mixture of lidocaine and prilocaine (EMLA) for 40 minutes, and 76 were allocated to group B and received the EMLA for 20 minutes plus skin cooling for 30 seconds. All participants completed the follow-up and were included in the intention-to-treat analysis. Three participants in group A were excluded from the per-protocol analysis due to minor protocol deviations (EMLA application duration shorter than the predefined per-protocol threshold). EMLA: Eutectic mixture of lidocaine and prilocaine; ITT: Intention-to-treat. Claude (Anthropic, San Francisco, CA, United States) was used to generate the foundational digital layouts and structural frameworks for this figure.

Figure 2 Mean Wong-Baker FACES Pain Rating Scale scores over time by treatment group. Pain scores were recorded before injection, immediately after injection, and 5 minutes after injection. The solid lines represent the mean pain scores for each group, and the shaded bands represent the 95% confidence intervals. The participants in group A received a eutectic mixture of lidocaine and prilocaine for 40 minutes, and those in group B received the eutectic mixture of lidocaine and prilocaine for 20 minutes plus skin cooling for 30 seconds. EMLA: Eutectic mixture of lidocaine and prilocaine. Claude (Anthropic, San Francisco, CA, United States) was used to generate the foundational digital layouts and structural frameworks for this figure.

Figure 3 Non-inferiority forest plot of adjusted mean differences in Wong-Baker FACES Pain Rating Scale scores between the groups. Estimates are presented as adjusted mean differences (group B minus group A), with corresponding 95% confidence intervals. Negative values indicate that the participants who received the eutectic mixture of lidocaine and prilocaine for 20 minutes plus skin cooling experienced less pain than those who received the eutectic mixture of lidocaine and prilocaine for 40 minutes. The dashed vertical line represents the prespecified non-inferiority margin of +1.4. Non-inferiority was confirmed when the upper boundary of the 95% confidence interval was below the prespecified margin. CI: Confidence interval. Claude (Anthropic, San Francisco, CA, United States) was used to generate the foundational digital layouts and structural frameworks for this figure.