The robot NAO, academic edition (Aldebaran Robotics) was used in this study. Some of its features include an on-board fully programmable computer CPU: x86 AMD Geode with 500 MHz, 256 MB SDRAM and 1 GB flash memory, WiFi (802.11g) and Ethernet, two cameras with up to 30 frames per second, two hands with self adaptive gripping abilities, force sensitive sensors on its arms and feet to perceive contact with objects, Light Emission Diodes in its eyes and body, four microphones to identify the source of sounds, and two loud speakers for communication where tone and voice pitch can be modified in real-time. It runs on a native Linux Operating system platform and can be programmed using a proprietary SDK called NaoQi, or in C, C++, Ruby and Urbi, which makes it compatible with other robot simulators such as Microsoft Robotics Developer Studio.

standard care procedures were used during the vaccination

The Faces Pain Scale-Revised was administered to children and their parents while in the waiting room and after consent was signed. Once this questionnaire and consent were completed, the parent and child entered the vaccination room for the vaccination. As soon as the vaccination was completed, the Faces Pain Scale-Revised was re-administered.

The Behavioral Approach-Avoidance Distress Scale was used by researchers one week after the data collection phase was completed while reviewing the videos.