Developing methodologies

In epidemiological research the development and application of valid, reliable and precise assessment methods is of major importance, and the methods must be acceptable for the participants. Such assessment methods are necessary in order to systematically map and monitor the development in dietary intake, physical activity and overweight of the population. High-quality assessment methods improve the basis for launching and assessing the impact of health-promoting initiatives.

Large population studies often involve subjective assessment methods such as questionnaires and diaries for determining diet, physical activity and overweight as objective methods rarely are practically applicable when studying a large number of people.

For assessing physical activity, objective methods are available, e.g. movement sensors, while this is not the case for diet. Objective assessment methods offer more reliable measurements and are thus recommended for monitoring developments over time and international comparisons.

The National Food Institute is continuously working to develop and carry out better, and for the respondents more acceptable assessment methods in order to improve the data basis for determining diet, physical activity and overweight in Denmark and internationally. The work involves both developing and validating new methodologies for assessing dietary intake and physical activity, but also improving existing methods currently used in the Danish National Survey of Diet and Physical Activity. The work also includes development of a series of photos for estimating portion sizes. Efforts are also made to incorporate new technology in the assessment methods, such as computer-based diet recording for children and youth, among other things to facilitate survey participation.

The National Food Institute has extensive  experience in applying both subjective and objective methods for assessing dietary intake, physical activity and overweight in different age groups (infants, children and youth, adults and senior citizens) through population surveys. For examples of the questionnaires that were used to measure dietary intake, physical activity and overweight in children and adults in the Nordic countries use the links in the right hand menu of this page: Monitoring dietary intake, physical activity and overweight in the Nordic countries. The questionnaires may be used freely.

The National Food Institute continually works to improve and implement better – and for the participants more acceptable – measuring methods. The aim is to improve on the database from which we determine dietary intake, physical activity and overweight both nationally and internationally. 

This work involves developing and validating new methods of assessing dietary intake and physical activity but also improving on existing methods including those used in the Danish National Survey of Diet and Physical Activity, DANSDA. This includes the development of a series of pictures for use in estimating portion sizes as well as the use of biomarkers (for measuring blood levels of vitamin D and iron) to estimate dietary intake. Work is also underway to make use of technology in measurement methods such as computer-based diet registration for children and young people, among other things to make it easier to participate.

In 2016-17 the institute is designing a computer assisted method based on the 2x24-hour recall method in order to validate and test the feasibility of this method against the currently used method in DANSDA, which is a seven day food record.  

Collaboration

Department of Sport Science
Linnaeus University, Kalmar
Department of Food, Nutrition and Sport Science, University of Gothenburg
University of Oslo
National Institute for Public Health and the Environment (RIVM)
French Agency for food, environmental and occupational health safety (ANSES)