Table 5.

Comparison of portion size estimation accuracy across the type of food presentation in the image-series validation study, the Norwegian version of myfood24

Difference in portion size estimations	Correct estimation		P
	Median	IQR
Food presentation
As depicted (n 36)	0⋅60	0⋅51	0⋅416
Not as depicteda (n 10)	0⋅63	0⋅43
Presented weight
Identical weight (n 23)	0⋅59	0⋅49	0⋅597
Altered weightb (n 23)	0⋅61	0⋅59

Mann–Whitney U test. Correct estimation referring to the participants’ mean proportion of correctly classified portion size image estimates per dish/food item, correctly classified defined as a perfect match between the portion size image chosen by the participant and the portion size of that same food or dish presented to the participant. Median represents the central tendency of the mean correct estimates per dish/food item, with interquartile range (IQR) representing the measure of variability.

^aPresented with a different plate or bowl than depicted.

^bPresented with ±25 % of the differential to an adjacent portion size image.