Shotblocker or Cold Application; Which One is More Effective in Reducing the Pain Associated With the Intramuscular Injection in Children: A Randomized Controlled Trial

The population of this study consisted of the children within the age range of 7-12 years who applied to the injection room in the pediatrics clinic of a university hospital between November 2017 and June 2018. On the other hand, the sample of this study consisted of 150 children who met the case-selection criteria and agreed to participate in the study.

In the Power analysis carried out based on the literature, the sample size of the study was determined as 150 with the confidence level of 90% (α=0.10). For 150 children, the power was β=0.20, 1-β=0.80 with α =.05. The approximate number of subjects was calculated as 50 per group with the Cohen's effect size of α = .05 and the confidence interval of 95%. The children in the sample were randomly assigned to the following groups: Cold application, Shotblocker, and control. In order to determine which case to include in which group, the numbers were randomly distributed to the 3 groups without repetition using a software. In the study, the sample size for each of the 3 groups, that is, cold application group (n=50), Shotblocker group (n=50), and control group (n=50) was determined as 50.

The intramuscular injection was carried out in the pediatric injection room of a university hospital. Before the intervention, the parents and children were met, they were informed about the study, and they were asked whether they would accept to participate in the study. The written and verbal consent were obtained from the parents and the children, respectively. In order to ensure reliability in the study results, the intramuscular injection was applied by the same nurse having at least 5 years of working experience throughout the study; and the pain behavior and anxiety levels of the children were evaluated by the same researcher. The parents were allowed to stay with their children during the intramuscular injection.

The following information was obtained from the children and parents who agreed to participate in the study using the Child Information Form: the socio-demographic characteristics of the children and parent, the previous history of IM injection, the previous history of being subject to a painful intervention, whether the child took an analgesic drug within the last 6 hours, the body mass index (BMI), etc. Prior to the intramuscular injection, the children's weight and height were measured and recorded. The same medicine (procaine penicilline) was administered to all children.

During the intramuscular injection, it was ensured that the environmental factors (temperature, light, noise, etc.), the injection site, and the antiseptic solution (70% alcohol) were standardized. The injection site was wiped using an antiseptic (batticon/chlorhexidine) cotton by gently pressing from center to periphery. It was ensured that the child was in the appropriate position, that is, in the prone position, with the toes facing inward. Prior to the injection, Shotblocker or the cold gel pad was introduced to the children in the experimental group and they were informed of how they would be used. Furthermore, the children and parents were informed about the Wong-Baker FACES® Pain Rating Scale and Children's Fear Scale (CFS) to be used in the study. The parents and children who volunteered to take part in the study were informed of the scale scoring. Which parent would take part in the study was left to the choice of parents to take participate. The CFS scale was evaluated preoperatively after receiving consent from the children and parents and completing the information form. The pain evaluation was made by the children, parents, and observers right after the procedure. When applying the scales, a particular attention was paid so that the children, parents and observers would not see each other's evaluation and not affect one another. Before the injection, the anxiety level was evaluated by the child, parent, and researcher using Children's Fear Scale (CFS). After the injection; the pain level was evaluated by the child, parent, and researcher using the Wong-Baker FACES® Pain Rating Scale, and the anxiety level was evaluated by the parent and researcher using Children's Fear Scale (CFS).