WHO European Childhood Obesity Surveillance Initiative (COSI)

The WHO European Childhood Obesity Surveillance Initiative (COSI) was set up as a response to the European Ministerial Conference on Counteracting Obesity. Member States recognized the need for harmonized surveillance systems, providing measured and comparable data on rates of overweight/obesity among primary-school children. Such data is essential to inform policy development within the European Region, indicate trends and provide an insight into the impact of action taken. COSI was a response to this need. The importance of, and political commitment to, such surveillance mechanisms has been reinforced  in the Vienna Declaration on Nutrition and Noncommunicable Diseases in the Context of Health 2020 and the European Food and Nutrition Action Plan 2015-2020.

Countries participating in COSI routinely measure trends in overweight and obesity in primary school children (6-9 years) in order to understand the progress of the epidemic in this population group, gain intercountry comparisons within the European Region and inform action to reverse the trend.

The COSI system does not aim to replace countries' existing health, anthropometric and dietary surveillance systems or those in the planning stages; on the contrary, the COSI approach has a strong potential to be integrated into existing systems if possible. Countries are expected to collect data according to COSI protocol, which allows each participating country to develop a system that fits its local circumstances.

Twenty-five countries (and the number is increasing) participate, including: (Albania, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Greece, Hungary, Ireland, Italy, Kazakhstan, Latvia, Lithuania, Malta, Norway, Poland, Portugal, Republic of Moldova, Romania, Slovenia, Spain, Sweden, The former Yugoslav Republic of Macedonia, and Turkey).

Prior to the introduction of COSI in a country, the country identifies an institute with responsibility for the overall national coordination and management, and assigns a Principal Investigator as the institute's authorized representative. This institute then signs a Collaboration Arrangement with the WHO Regional Office for Europe that describes the roles of the participating country and the Regional Office, including data release and publication policies, principles, terms and procedures.

Network meetings took place in June 2007 (Paris, France), December 2007 (Maceira, Portugal), June 2009 (Copenhagen, Denmark), February 2010 (Rome, Italy), July 2011 (Lisbon, Portugal), November 2012 (Oslo, Norway) and February 2014 (Athens, Greece).