Data collection for clinical, behavioral, and social research has traditionally been accomplished via paper-and-pencil forms collected in-person, by telephone, or through the mail; however, recent technological advances have resulted in a multitude of online data collection systems (DCS) that deploy measures and collect data online. More than 35% of all data collection is now being conducted through online surveys. Furthermore, evidence indicates online data collection offers higher response rates, higher quality data, and substantial cost savings over traditional methods. Unfortunately, however, none of the current technology products offer developmentally appropriate tools specifically designed for collecting data with children younger than 13. This Phase II SBIR project will continue development and testing of a child-friendly data collection system, Quest, providing game-like user interfaces with built-in accessibility tools to maximize both engagement and usability for children and enabling researchers to design, build, and deploy developmentally appropriate surveys for children (ages 6-12). This Phase II SBIR project will build on positive Phase I feedback and support to accomplish three specific aims: (1) Fully develop Quest software by finalizing user flows and interfaces, embedding recommended software features and functions, and integrating researcher and child portal components. To ensure maximum usability, we will employ an iterative development model incorporating continuous feedback from children and researchers during development of the full product. (2) Conduct usability testing with children ages 6-12 who will be randomly assigned to complete pediatric self-report social behavioral measures using one of three data collection methods: (a) paper-and-pencil, (b) online survey, or (c) Quest. Observational data and ratings will be gathered for each method to assess participant engagement, motivation, attention, and usability. (3) Conduct pilot testing with pediatric clinical, social, and behavioral researchers randomly assigned to (a) Quest or (b) data collection as usual (DCU) conditions. Researchers will complete ratings of their data collection experience with children over a 3-month period. We expect researchers in the Quest condition to report significantly greater (a) ease of use, (b) data quality, (c) participant engagement, (d) cost savings, and (e) method satisfaction compared to researchers in the DCU condition. We also expect them to report the Quest software is (a) highly innovative, (b) feasible, and (c) valuable for conducting research with children. This project will yield a highly innovative, affordable product that can be broadly applied in the service of clinical, behavioral, and social research and for which there is a demonstrated market need. In effect, this work will support NCATS’s Strategic Priorities to build research capacity by addressing the developmental challenges of data collection with children and supporting researchers’ capacity to collect high quality survey data with children, which in turn, would support efforts to translate research findings into clinical practice so that health outcomes for children can be enhanced.