TABLE 1.

Tasks and estimated time associated with each task needed to carry out the fieldwork training necessary for data collection for the impact evaluation of the Chilean Law of Food Labeling and Advertising¹

Task	Responsible	Estimated time
Training with designated fieldworker coordinator on all the subsequent training and work required for data collection	Principal or co-investigators; fieldwork coordinator	8 h
Presentation
General introduction	Principal or co-investigators	1 h
Introduction to data collection in the field	Fieldwork coordinator	2.5 h
Introduction to photography of food packages	Fieldwork coordinator	0.5 h
Practical session: photographing food packages in controlled (institution) setting	Fieldwork coordinator with fieldworkers	2.5 h
Recommended practical session: advanced photography training with a professional or highly experienced photographer (optional depending on quality of camera)	Professional or highly experienced photographer; fieldworkers	5–6 h
Optional weekend practice: fieldworkers practice taking food package photos at home	Fieldworkers	3 d
Practical session: half-day training simulation in a supermarket	Fieldwork coordinator with fieldworkers	4 h

¹Before training, it is important to obtain an agreement with desired supermarkets or other food establishments, which could take ≥2 mo.