The research was conducted as a randomized controlled experiment to investigate the effect of Buzzy® on pain level during the measles-rubella-mumps (MMR) vaccine injection in 12-month-old infants. This study was done with infants meeting the sampling criteria (buzzy group: 30, control group: 30) on November 2018-May 2019 in Istanbul Bakirkoy 9 Family Health Center.

To determine the effect of Buzzy® application on pain, which is a combination of cold and vibration, during measles-rubella-mumps (MMR) vaccine injection administration on 12-month-old infants. The study is a randomized contrlled experimental research. The research sample is composed of 60 infants (buzzy:30, control:30) who are 12-month-old injected MMR vaccine at Bakırköy No. 9 Family Health Center between November 2018-May 2019. As a data collection tool Data Collection Form, FLACC Pain Scale and Buzzy® device have been used. While Buzzy® was applied on infants in the trial group before, during and after the vaccine injection, the infants in the control group were applied routine vaccine injection. The pain response of the infants was evaluated by the nurse and the parent before, during and after the vaccine injection and the physiological parameters were evaluated by the nurse before and after the vaccine injection.

Inclusion Criteria:

• The baby has completed 12 months,
• MMR vaccine will be applied,
• Being at a suitable weight for the month,
• The baby has not been given analgesic medication during the day,
• It can be listed as the parent's willingness to participate in the research.

Exclusion Criteria:

• It can be listed as having a body temperature above 37.5.