Objective methods, such as accelerometers, have become a preferred option when measuring population levels of physical activity, examining trends in activity patterns and when examining associations between activity and health outcomes in young people.
The International Children’s Accelerometry Database (ICAD) project is a consortium including 20 partners which pooled and reduced raw accelerometer data using standardized methods to create comparable outcome variables in 32,000 young people aged 3 to 18 years across studies from Europe, the US, Brazil and Australia.
By pooling and reanalysing accelerometer data from different studies the ICAD has the potential to; a) increase statistical power due to a large sample size, b) create a more heterogeneous and potentially more representative sample, c) standardize and optimize the analytical methods used in the generation of outcome variables, and d) provide a means to study the causes of inter-study variability in physical activity.
The ICAD project was funded by the National Prevention Research Initiative in the UK and is led by a steering committee including representatives from MRC Epidemiology Unit (Prof. Ulf Ekelund, Dr. Esther van Sluijs), University of Bristol (Prof. Ashley Cooper, Dr. Angie Page), Loughborough University (Dr. Lauren Sherar, Dr. Dale Esliger) and Norwegian School of Sports Scineces (Prof. Ulf Ekelund).
The database is managed by the MRC Epidemiology Unit and is publicly available for data requests.
Applying to use ICAD data
The ICAD is open for data request as a supported access rescource. Please find information regarding the application process to access the data below. Data will be released in chronological order by date of accepted proposals and usually within 5 to 10 working days. Please contact Dr Lauren Sherar with data requests using the application form below:
- General instructions
- Data Dictionary (Accelerometer data, Non-accelerometer data)
- ICAD application form
- Data use agreement
Publishing and presenting ICAD Data
- ICAD approved proposals and progress (updated October 2014)
- List of ICAD partners
- Log of changes to ICAD database
- Sherar L, Griew P, Esliger D, Cooper A, Ekelund U, Judge K, Riddoch C. International children’s accelerometry database (ICAD): Design and methods. BMC Public Health, 2011 [full text]
- Ekelund U, Luan JA, Sherar LB, Esliger DW, Grew P, Cooper A. Moderate to Vigorous Physical Activity and Sedentary Time and Cardiometabolic Risk Factors in Children and Adolescents. JAMA 2012; 307: 704-712 [full text]
- Kwon S, Janz KF; International Children’s Accelerometry Database (ICAD) Collaborators. Tracking of accelerometry-measured physical activity during childhood: ICAD pooled analysis. Int J Behav Nutr Phys Act 2012; 9:68 [full text]
- Atkin AJ, Sharp SJ, Corder K, van Sluijs EM; on behalf of the International Children’s Accelerometry Database (ICAD) Collaborators. Prevalence and correlates of screen time in youth: an international perspective. Am J Prev Med. 2014 Sep 16 [full text]
Studies that have contributed data
NHANES (wave 2003/2004 and 2005/2006)
Project TAAG (Trial of Activity for Adolescent Girls)
CHAMPS (Physical Activity in Pre-School Children)
1993 Pelotas Birth Cohort
European Youth Heart Study (Norway, Portugal, Estonia and Denmark)
PEACH Project (Personal and Environmental Association with Children’s Health)
Project MAGIC (Movement and Activity Glasgow Intervention with Children’s Health)
ALSPAC (Avon Longitudinal Study of Parents and Children)
Project SPEEDY (Sport Physical Activity & Eating Behaviour: Environmental Determinants in Young People)
CHAMPS (Children’s Health and Activity Monitoring Program)
The Copenhagen School Children Intervention Study
Belgium Pre-school Study
Swiss Ballabeina Study
Swiss Kinder-Sportstudie (KISS) Study
Project CLAN (Children Living in Active Neighbourhoods)
Project HEAPS (Healthy Eating And Play Study)