The Effect of Using Distraction Card and Squeezing Emotion-Regulation Toy on Pain and Pain-Related Fear During Intramuscular Vaccination in Children Aged 4-7 Years: A Single-Center, Parallel-Group, Randomized Experimental Study

The study is planned as a single-center, randomized experimental trial with two parallel active intervention groups. The study population will consist of children aged 4-7 years for whom intramuscular tetanus vaccination is planned at Mersin University Hospital.

The sample size was calculated using a priori power analysis based on an effect size of d = 0.714 from Ugucu et al. (2022), with alpha = 0.05 and power = 0.80. The final sample is planned as 68 children, with 34 children in each intervention group.

The Pediatric Vaccination/Injection Unit will be arranged to provide the same environmental conditions for all children and parents, including lighting, temperature, noise level, seating, and procedural workflow. It is decorated with cartoon characters and ornaments. Only one child will undergo the procedure in the room at a time. Routine practice will support parental presence during the invasive procedure. The nurse who performs the intramuscular tetanus vaccination will be the same for both groups and children where feasible and will have pediatric clinical experience.

Before the procedure, children will receive an explanation appropriate to their developmental level, and their physical comfort will be ensured. In the distraction-card group, the child will begin using age-appropriate distraction cards two minutes before the intramuscular injection. The child will be actively engaged with the cards through visual attention and simple developmentally appropriate prompts until the injection procedure is completed. In the emotion-regulation toy-squeezing group, the child will begin squeezing an age-appropriate emotion-regulation toy two minutes before the intramuscular injection and will continue until the procedure is completed.

Pain and pain-related fear scores will be recorded by the researchers two minutes before the procedure, during the procedure at needle insertion/vaccine administration, and one minute after the procedure. Data will be collected during the routinely planned intramuscular tetanus vaccination procedure without delaying or replacing standard clinical care.