This randomized controlled trial investigates the effects of using a musical toy (xylophone) as a distraction technique during peripheral intravenous cannulation on pain, fear, and parental satisfaction in hospitalized children aged 3 to 6 years. The study will be conducted in the Pediatric Health and Diseases Clinic of Trakya University in Edirne, Turkey.

A total of 64 children will be randomly assigned to either the intervention group or the control group. Children in the intervention group will be encouraged to play with a xylophone, accompanied by a nurse, before and during the cannulation procedure. The control group will receive standard care without any distraction. Pain levels will be measured using the Wong-Baker FACES Pain Rating Scale, fear will be assessed using the Children's Fear Scale, and parental satisfaction will be evaluated using the PedsQL Healthcare Satisfaction Scale.

The primary objective of this randomized controlled trial is to evaluate whether the use of a musical toy during peripheral intravenous cannulation reduces procedural fear in preschool children.

Secondary objectives are to determine whether the intervention reduces procedural pain and improves parental satisfaction with the healthcare experience

This study is expected to contribute to the evidence base supporting the use of non-pharmacological methods in pediatric pain management and to promote child-friendly approaches in clinical settings.

Inclusion Criteria:

• Children aged between 3 and 6 years
• Hospitalized and scheduled for peripheral intravenous cannulation
• No hearing or mental disabilities
• No chronic disease associated with pain
• No analgesic use in the past 6 hours
• One parent present during the procedure
• Both child and parent voluntarily agree to participate
• Intravenous cannulation to be performed in a single attempt
• Parent/guardian is literate

Exclusion Criteria:

• Children with hearing impairment or mental disabilities
• Use of analgesics within the last 6 hours
• Presence of chronic pain conditions
• Parental refusal to participate
• Failed intravenous cannulation attempt
• Illiterate parent/guardian
• Any parental mental disability
• Child or parent unwilling to participate

Due to the nature of the intervention, children, parents, and the nurse delivering the intervention could not be blinded. Outcome assessments (fear and pain) were conducted using video recordings evaluated by an independent researcher who was blinded to group assignment. All recordings were coded and anonymized. The statistician performing the analysis was also blinded, and group labels were masked (Group A and Group B) during statistical analysis to minimize detection and analytical bias.