The Sleep and Activity Database for the Early Years (SADEY)   

SADEY aims to provide evidence from a large sample of young children (<6 years) on the optimal daily levels and compositions of physical activity, sedentary behaviour and sleep needed for healthy growth and development. The specific objectives of SADEY are:

  • To develop an international database of physical activity, sedentary behaviour and sleep for children of the early years.
  • To identify how much daily physical activity, sedentary behaviour and sleep is associated with the best physical, social-emotional, cognitive and motor development outcomes for young children.

The database will include pooled international data on children’s movement behaviours including device-measured data from Actigraph accelerometers and parent-reported survey data (e.g., sleep and screen time) as well as measures of physical, social-emotional, cognitive, language, and motor development.


SADEY is governed by a Leadership Group including Dr Dylan Cliff and Prof Ian Janssen (Co-Lead Researchers), Prof Tim Olds, Dr Esther van Sluijs, Prof Mark Tremblay, A/Prof Catherine Draper, A/Prof Diego Augusto Santos Silva, Prof Fan Jiang, and Prof Rute Santos.


Contribute to the Database or Access the Database for Research Purposes


SADEY is the result of a growing network of international 24-hour movement behaviour researchers who will be sharing this unique database. Researchers who would like to collaborate on SADEY by contributing study data on young children’s 24-hour movement behaviours and health outcomes can contact the SADEY team at Data contributors will be invited to be co-authors on all SADEY papers that use their data and will have first access to the database to lead their own papers.


For additional information about the SADEY team and project, please see the following link –


Or contact the SADEY Team with your enquiries at