In 2014 the Danish Government introduced a wide-ranging school reform that applies to all public schools in Denmark. The reform involved changes in several aspects of the school structure and content. In a physical activity promotion perspective, a distinctive feature of the school reform is that it has become mandatory to integrate an average of 45 minutes of daily physical activity during the regular school day. The overarching objective of the PHASAR study is to evaluate the implementation of this ambitious policy-driven physical activity promotion initiative and the possible effect on children's level of physical activity and overweight. Moreover, by applying improved accelerometry technology, the study aims to provide a detailed characterization of physical activity during the children's entire day including the school day.~The evaluation is divided into a quantitative effect evaluation and a combined quantitative and qualitative process evaluation. A total of 31 schools were enrolled and 2,683 pairs of accelerometers were handed out to school-aged children from 1st to 9th grade in the PHASAR study during the 2017/18 school year. The objectively measured physical activity data will be compared to repeated cross-sectional data collected in four historical school-based studies from 1998-2012. Body mass index data from 2012-2018 will be collected from The Child Database, which includes repeated cross-sectional assessments on approximately 100,000 children annually. In the absence of a control group, interrupted time-series analysis will be used to evaluate pre- and post-reform physical activity and body mass index levels and trends. A characterization of the school environment relevant for physical activity promotion on a political, environmental, organizational and individual level, as well as school implementation processes will be conducted to evaluate the implementation process. Data will be collected using interviews, surveys, document analyses and observations.~The PHASAR study provides a rare opportunity to evaluate the effectiveness of a nation-wide policy-driven school-based physical activity promotion initiative. The use of objectively measured pre- and post-reform physical activity and body mass index data combined with a characterization of the school implementation processes regarding the promotion of physical activity will provide a comprehensive source of information needed to evaluate the school reform.
In 2014 the Danish Government introduced a wide-ranging school reform that applies to all public schools in Denmark. In a physical activity promotion perspective, a distinctive feature of the school reform is that it has become mandatory to integrate an average of 45 minutes of daily physical activity in the regular school day. The overarching objective of the PHASAR study is to evaluate the implementation of this ambitious policy-driven physical activity promotion initiative and its potential effect on physical activity and overweight.~The PHASAR study provides a rare opportunity to evaluate the effectiveness of a nation-wide policy-driven school-based physical activity promotion initiative.