The study design and data collection procedures
| . | Self-service restaurant 1 Vocational school restaurant . | Self-service restaurant 2 Spa hotel restaurant . |
|---|---|---|
| Lunch buffet details | ||
| Lunch served daily | 10.30 am–12.30 pm | 11 am–1 pm |
| Customer profile | Approx. 80% of students are from high schools and vocational schools; the rest are customers and school employees | Approx. 65–70% are pensioners in spa rehabilitation, approx. 25–30% are adults, <5% are families with kids |
| Food consumption data collection (three days in each research week including Tues., Weds., Thurs.) | ||
| Control period | Week 8/2022 | Week 17/2022 |
| Number of customers | 704 (232, 217, 255) | 972 (338, 315, 319) |
| Intervention (nutrition label) period | Week 13/2022 | Week 19/2022 |
| Number of customers | 1,006 (364, 295, 347) | 835 (303, 243, 289) |
| . | Self-service restaurant 1 Vocational school restaurant . | Self-service restaurant 2 Spa hotel restaurant . |
|---|---|---|
| Lunch buffet details | ||
| Lunch served daily | 10.30 am–12.30 pm | 11 am–1 pm |
| Customer profile | Approx. 80% of students are from high schools and vocational schools; the rest are customers and school employees | Approx. 65–70% are pensioners in spa rehabilitation, approx. 25–30% are adults, <5% are families with kids |
| Food consumption data collection (three days in each research week including Tues., Weds., Thurs.) | ||
| Control period | Week 8/2022 | Week 17/2022 |
| Number of customers | 704 (232, 217, 255) | 972 (338, 315, 319) |
| Intervention (nutrition label) period | Week 13/2022 | Week 19/2022 |
| Number of customers | 1,006 (364, 295, 347) | 835 (303, 243, 289) |
Note(s): Identical menus, meaning the same foods, were served in the study restaurants during both the control and intervention periods (see Supplementary Material for more information). For each research, the food intake over a span of three days was measured, and then divided by the total number of customers during that same period
Source(s): Authors’ work