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Currently submitted to: Journal of Medical Internet Research

Date Submitted: Aug 2, 2019
Open Peer Review Period: Aug 5, 2019 - Sep 20, 2019
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The Kids Obesity Prevention program (KOP): A cluster randomized controlled trial to evaluate a serious game for the prevention and treatment of childhood obesity

  • Isabelle Mack; 
  • Nadine Reiband; 
  • Carolin Etges; 
  • Sabrina Eichhorn; 
  • Norbert Schaeffeler; 
  • Guido Zurstiege; 
  • Caterina Gawrilow; 
  • Katja Weimer; 
  • Riyad Peeraully; 
  • Martin Teufel; 
  • Gunnar Blumenstock; 
  • Katrin Giel; 
  • Florian Junne; 
  • Stephan Zipfel; 



Health games provide opportunities for the treatment and prevention of childhood obesity. We developed a motion-controlled serious game for children that addresses three core topics of nutrition, physical activity and stress coping. It is the first serious game which extensively targets the dietary energy density principle (DED-P) in relation to nutrition. The game is intended to provide an additional educational component for the prevention and treatment of obesity in children.


To evaluate the newly developed game and evaluate how well children are able to understand and apply the DED-P.


This cluster-randomized, controlled trial collected data from 82 primary school children aged 9 to 12 years and their parents at baseline (T0), 2 weeks after study commencement (T1) and at 4 weeks follow-up (T2). The drop out rate was 3.6%. The intervention group (IG) played the game within 2 weeks (two sessions with different game modules). One part of the game involves selection of the food with the lower energy density when presented with a pair of foods. This allows assessment of whether the children have understood the DED-P, and also whether they can apply it to unknown foods under time pressure. The control group (CG) received a brochure about the food pyramid concept and physical activity. Primary outcome was the gain of knowledge (nutrition, stress coping) applying a pre-tested questionnaire. Secondary outcomes were the maintenance of knowledge, application of the DED-P, feelings during game play, game acceptance and behavioral measures (physical activity, media consumption, dietary intake).


The knowledge score ranging from 0 to 100 increased from T0 (IG: 53(10), CG: 50(11)) to T1 (IG: 69(11), CG: 52(12)) in IG versus CG (p<.001). At T2, the knowledge score of IG remained at the same level. Game data show that after DED-P education, the classification under time pressure of unknown versus known food pairs according to their DED category was similar (hit rate around 70%). 95% of the children liked the game very much or much. No group changes were observed at behavioral level.


KOP sustainably increases knowledge in the areas of nutrition and stress coping and children were able to apply the DED-P. Clinical Trial: NCT02551978.


Please cite as:

Mack I, Reiband N, Etges C, Eichhorn S, Schaeffeler N, Zurstiege G, Gawrilow C, Weimer K, Peeraully R, Teufel M, Blumenstock G, Giel K, Junne F, Zipfel S

The Kids Obesity Prevention program (KOP): A cluster randomized controlled trial to evaluate a serious game for the prevention and treatment of childhood obesity

JMIR Preprints. 02/08/2019:15725

DOI: 10.2196/preprints.15725


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