Table 3.
Summary of participants classified as positive, non and negative responders to portion size reductions.
| Large-normal vs. smaller than normal portion size |
Large-normal vs. small-normal portion size |
Small-normal vs. smaller than normal portion size |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| +ve responder | Non responder | -ve responder | +ve responder | Non responder | -ve responder | +ve responder | Non responder | -ve responder | |
| Study 1 (n = 45) | 33 (73%) | 8 (18%) | 4 (9%) | 26 (58%) | 9 (20%) | 10 (22%) | 24 (53%) | 11 (24%) | 10 (22%) |
| Study 2 (n = 36) | 26 (72% | 6 (17%) | 4 (11%) | 15 (42%) | 14 (39%) | 7 (19%) | 21 (58%) | 10 (28%) | 5 (14%) |
| Study 3 (n = 30) | 21 (70%) | 8 (27%) | 1 (3%) | 15 (50%) | 12 (40%) | 3 (10%) | 12 (40%) | 14 (47%) | 4 (13%) |
| Across studies (n = 111) | 80 (72%) | 22 (20%) | 9 (8%) | 56 (51%) | 35 (32%) | 20 (18%) | 57 (51%) | 35 (32%) | 19 (17%) |
+ve responder refers to number of participants whose energy intake was reduced by 10% or more when comparing energy intake in the larger portion size condition vs. smaller portion size condition of contrast (eating less in smaller portion condition of contrast). Non-responder refers to number of participants who energy intake was between +9.9% and −9.9% when comparing energy intake in the larger portion size condition vs. smaller portion size condition of contrast. –ve responder refers to number of participants whose energy intake was increased by 10% or more when comparing energy intake in the larger portion size condition vs. smaller portion size condition of contrast (eating more in smaller portion condition of contrast).