Case Control Study for Nudge in School Canteens

Last registered on June 25, 2024


Trial Information

General Information

Case Control Study for Nudge in School Canteens
Initial registration date
May 15, 2024

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published
June 25, 2024, 2:15 PM EDT

First published corresponds to when the trial was first made public on the Registry after being reviewed.


Primary Investigator

ENS de Lyon

Other Primary Investigator(s)

PI Affiliation
ENS de Lyon, department of Economics

Additional Trial Information

Start date
End date
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
This paper tackles the issue of ongoing food waste in school canteens. We design a case control study for applying nudge in school canteens to curb food waste. Firstly, we write a protocol for a pilot study. Then, we propose an extended protocol for a large scale experiment. Our main contribution to the research field is to provide a nudge that is interactive. It is a revisited "Climate Fresk" between searchers, school canteen staff, teachers and children aged from 11 years old to 15 years old. We expect to reduce significantly the amount of food waste during the one-month experiment.
External Link(s)

Registration Citation

Campone, Virgile and Anthony Rocher. 2024. "Case Control Study for Nudge in School Canteens." AEA RCT Registry. June 25.
Experimental Details


The nudge is called "Game against Food Waste". It is a jigsaw puzzle and it involves pupils as well as canteen staff members, teachers and searchers. We have 40 cards with concepts, places, numbers and diagrams that must help to contemplate food waste as systemic issue. The point of our nudge is to make children thinking actively on their food practices.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
We expect a reduction in quantity wasted at the end of the experiment.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
The study focuses on middle schools in the Region Auvergne Rhône Alpes because it is the most performing region after the Region Île de France (Paris) [Préfecture de la région Auvergne-Rhône- Alpes, 2024]. The region that has the advantage of not having either the red tape or the political games of the Paris region. It is an extremely dynamic region, and also geographically diverse. As a result, it is an exemplary open-air laboratory for economic research. Furthermore, it is one of the leading regions in term of public policy against food waste in school canteens [Région Auvergne- Rhône-Alpes, 2024]. Besides, the region has with super-scale cities such as Lyon, medium-scale cities as Grenoble and Saint-Etienne and along with rural areas. It is suitable for a proper random sampling, as it will be mentioned herein-after. Last but not least, as the laboratory is located in Lyon, it is easier to work in this Region. Hence, logistically and politically it is cogent to work with the Region Auvergne Rhone Alpes.
Experimental Design Details
Not available
Randomization Method
The case-control study is conducted with a sample extracted from the 827 middle schools. First, to have homogeneity the population of the 827 middle school is divided into two groups: urban and rural. In fact, the case-control study is well-performing if and only if the population compared are the same. According to the Region, in 2022 35,1 % of the students in middle schools lived in rural areas while 64,1 % lived in urban areas [Prinzis, 2022]. It is a proxy for the distribution of middle schools in the territory. Hence, there is 536 middle schools in urban areas and 291 middle schools in rural areas. We use Cocheran’s formula to determine the size of our sample. We find that the cardinal of the sampled urban middle school is 225. And the cardinal of the sampled rural school is 166.
Randomization Unit
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
391 Schools.
Sample size: planned number of observations
534408 Pupils
Sample size (or number of clusters) by treatment arms
20 Schools control
20 Schools Test including :
- 10 Schools Rural
- 10 Schools Urban
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Institutional Review Boards (IRBs)

IRB Name
IRB Approval Date
IRB Approval Number