Introducing the Front-Of-Pack Acceptance Model: the role of usefulness and ease of use in European consumers’ acceptance of Front-Of-Pack Labels

Figures & data

Table 1. Sample size and characteristics per study.

	Preliminary study			Study 1		Study 2
	Initial phase	Advanced phase		UK	France	Multiple Traffic Light	Nutri-Score	NutrInform Battery
Variables	Italy	France	UK
	(n = 61)	(n = 150)	(n = 138)	(n = 800)	(n = 673)	(n = 318)	(n = 303)	(n = 319)
Age
Under 18	0.0%	0.8%	1.6%	0.1%	0.0%	0.0%	0.0%	0.0%
18–24	71.0%	32.0%	16.3%	12.9%	34.2%	0.6%	0.6%	0.9%
25–34	29.0%	35.2%	41.1%	29.1%	31.3%	49.1%	50.3%	48.6%
35–44	0.0%	22.6%	20.9%	25.6%	21.0%	31.1%	33.1%	31.1%
45–54	0.0%	5.5%	13.2%	16.0%	7.1%	13.1%	11.9%	14.2%
55–64	0.0%	3.1%	5.4%	11.9%	6.1%	4.9%	3.5%	4.3%
65+	0.0%	0.8%	1.5%	4.4%	0.3%	1.2%	0.6%	0.9%
Education
Less than high school	0.0%	2.3%	1.6%	2.1%	1.2%	0.6%	0.6%	1.9%
High-school graduate	0.0%	10.2%	31.0%	26.3%	14.2%	27.1%	22.1%	29.5%
College/bachelor or equivalent	0.0%	39.1%	43.9%	53.1%	38.2%	35.1%	41.7%	35.1%
Master of science/master of arts or equivalent	100.0%	43.7%	19.9%	15.9%	40.9%	29.9%	28.9%	28.0%
Doctorate	0.0%	4.7%	3.6%	2.6%	5.5%	7.3%	6.7%	5.5%
Gender
Male	56.0%	57.8%	25.6%	32.5%	51.6%	48.8%	44.2%	49.1%
Female	44.0%	34.4%	68.2%	67.2%	46.5%	50.0%	55.2%	49.7%
Non-binary/third gender	0.0%	6.2%	4.7%	0.2%	1.5%	0.9%	0.0%	0.6%
Prefer not to say	0.0%	1.6%	1.5%	0.1%	0.4%	0.3%	0.6%	0.6%
Occupation
Employed full time	0.0%	46.1%	45.0%	54.6%	43.1%	51.8%	49.4%	51.2%
Employed part time	0.0%	12.5%	23.0%	18.6%	13.0%	20.1%	20.2%	18.3%
Unemployed looking for a job	0.0%	10.9%	9.8%	3.9%	10.8%	12.8%	10.9%	12.1%
Unemployed not looking for a job	0.0%	2.3%	8.5%	7.5%	3.0%	2.1%	3.8%	3.8%
Retired	0.0%	1.6%	3.6%	7.1%	1.2%	0.9%	15.4%	0.9%
Student	100.0%	25.0%	8.5%	6.9%	28.3%	12.3%	0.3%	13.7%
Disabled	0.0%	1.6%	1.6%	1.4%	0.6%	0.0%	0.0%	0.0%
Income
	0.0%	32.8%	18.6%	16.0%	39.1%	25.3%	26.3%	24.2%
10,000€–19,999€	0.0%	15.6%	20.9%	19.0%	17.8%	24.1%	21.5%	28.9%
20,000€–39,999€	0.0%	22.7%	38.0%	40.4%	23.4%	34.1%	37.8%	31.1%
40,000€–59,999€	0.0%	18.8%	11.6%	16.6%	12.0%	9.1%	10.6%	10.5%
60,000€–89,999€	71.0%	3.9%	7.5%	5.5%	4.6%	5.8%	2.8%	5.0%
90,000€–99,999€	27.0%	2.3%	2.1%	1.5%	0.6%	1.0%	0.0%	0.0%
	2.0%	3.9%	1.3%	1.0%	2.5%	0.6%	1.0%	0.3%

Table 2. Set of items deriving from the early stage of the preliminary phase.

Construct(s)	Item(s)	Normalised Score	Cluster	Selected
Perceived Usefulness (PU)	Using Food FOP improves the quality of the food purchase I do	10.9	1	Selected
	Overall, I find the Food FOP useful in my food purchase	9.31	1	Selected
	Food FOP give (will give) me access to useful food purchase information	8.59	1	Selected
	Food FOP are (will be) very beneficial to me	7.52	1	Selected
	For me food FOP for food purchase has great value	7.17	1
	Food FOP make (will make) me a smarter buyer	6.03	1
	Using food FOP improves my food purchase	14.79	2	Selected
	Using food FOP gives me greater control over my food purchase	14.34	2	Selected
	The food FOP addresses my food purchase-related needs	12.34	2	Selected
	Food FOP supports critical aspects of my food purchase	10.86	2	Selected
	Using Food FOP enhances my effectiveness on the food purchase	8.28	2	Selected
	Using food FOP saves me time	10.69	3	Selected
	Food FOP enables me to accomplish food purchase more quickly	10.24	3	Selected
	Using Food FOP reduces the time I spend on unproductive food purchase activities	7.76	3	Selected
	Using Food FOP makes it easier to do my food purchase	7.03	3	Selected
	Using Food FOP increases my food purchase productivity	6.69	3
	Food purchase would be difficult to perform without food FOP	10.83	NA	Selected
	Food FOP allows me to accomplish more tasks than would otherwise be possible	7.62	NA
Perceived Ease Of Use (PEOU)	My interaction with the Food Front-Of-Pack is easy for me to understand	14.28	1	Selected
	Overall, I find the Food Front-Of-Pack easy to use	13.97	1	Selected
	It is easy to learn how to use food Front-Of-Pack for food purchase	13.76	1	Selected
	I find it easy to get the Food Front-Of-Pack to do what I want it to do	13.17	1	Selected
	It is easy for me to remember how to perform food purchase using the Food Front-Of-Pack	12.76	1	Selected
	The Food Front-Of-Pack provides helpful guidance in performing food purchase	12.59	1	Selected
	I find it cumbersome to use the Food Front-Of-Pack	9.48	2	Selected
	I need to consult the user/reference manual/App often when using food Front-Of-Pack	8.59	2	Selected
	I often become confused when I use the food Front-Of-Pack label	9.76	3	Selected
	I make errors frequently when using food Front-Of-Pack label	9.59	3	Selected
	Interacting with the Food Front-Of-Pack is often frustrating	9.03	3	Selected
	Interacting with the Food Front-Of-Pack requires a lot of my mental effort	8.86	3	Selected
	Find it easy to recover from errors encountered while using food Front-Of-Pack	10.45	NA
	The Food Front-Of-Pack often behaves in unexpected ways	9.76	NA
	The food Front-Of-Pack is rigid and inflexible to interact with	8.97	NA

***p < 0.001

Table 2a. Convergent validity of the reduced set of items.

Construct(s)	Item(s)	M	SD	CFA loading	SMC	t value	p	α	AVE
Perceived Usefulness (PU)	Food Front-Of-Pack label give (will give) me access to useful food purchase information	5.37	1.35	0.834	0.617	16,036	***	0.916	0.731
	Food Front-Of-Pack label are (will be) very beneficial to me	5.08	1.43	0.907	0.723	18,340	***
	Using Food Front-Of-Pack label improves my food purchase	4.96	1.38	0.869	0.691	17,116	***
	Using Food Front-Of-Pack label gives me greater control over my food purchase	5.15	1.41	0.806	0.610	15,222	***
Perceived Ease of Use (PEOU)	My interaction with the Food Front-Of-Pack label is easy for me to understand	5.85	1.20	0.880	0.833	17,249	***	0.895	0.747
	Overall, I find the Food Front-Of-Pack label easy to use	5.95	1.14	0.917	0.625	18,312	***
	It is easy to learn how to use Food Front-Of-Pack label for food purchase	5.88	1.23	0.791	0.791	14,743	***

Table 2b. Discriminant validity of the reduced set of items.

	Perceived usefulness	perceived ease of use
Perceived usefulness	0.731
Perceived ease of use	0.633	0.747

Table 2c. Final set of items in Study 2.

Construct(s)	Item(s)
Perceived Usefulness (PU)	Food Front-Of-Pack label give (will give) me access to useful food purchase information
	Food Front-Of-Pack label are (will be) very beneficial to me
	Using Food Front-Of-Pack label improves my food purchase
	Using Food Front-Of-Pack label gives me greater control over my food purchase
Perceived Ease of Use (PEOU)	My interaction with the Food Front-Of-Pack label is easy for me to understand
	Overall, I find the Food Front-Of-Pack label easy to use
	It is easy to learn how to use Food Front-Of-Pack label for food purchase

Table 3a. Model assessment – convergent validity.

Item(s)	UK (n = 800)								France (n = 673)
	M	SD	CFA loading	SMC	t value	p	α	AVE	M	SD	CFA loading	SMC	t value	p	α	AVE
Food Front-Of-Pack label give (will give) me access to useful food purchase information	5.540	1.140	0.771	0.555	18.479	***	0.924	0.771	4.994	1.329	0.807	0.599	24.992	***	0.924	0.756
Food Front-Of-Pack label are (will be) very beneficial to me	5.330	1.307	0.921	0.773	14.020	***			4.782	1.369	0.893	0.714	29.382	***
Using Food Front-Of-Pack label improves my food purchase	5.090	1.390	0.922	0.791	13.891	***			4.896	1.395	0.911	0.768	30.408	***
Using Food Front-Of-Pack label gives me greater control over my food purchase	5.260	1.374	0.862	0.704	16.949	***			4.848	1.430	0.863	0.691	27.792	***
My interaction with the Food Front-Of-Pack label is easy for me to understand	5.970	0.980	0.911	0.769	13.477	***	0.936	0.832	5.878	1.084	0.796	0.563	24.477	***	0.888	0.734
Overall, I find the Food Front-Of-Pack label easy to use	6.020	0.987	0.947	0.797	9.253	***			5.997	1.056	0.918	0.704	29.776	***
It is easy to learn how to use Food Front-Of-Pack label for food purchase	6.050	0.955	0.876	0.711	15.850	***			5.990	1.058	0.85	0.628	26.441	***
		0.000
I am positive about the Front-Of-Pack label t for food purchase	5.620	1.183	0.914	0.726	14.421	***	0.933	0.828	5.596	1.320	0.906	0.737	30.134	***	0.929	0.816
The use of the Front-Of-Pack label for food purchase is a good idea	5.930	1.039	0.898	0.762	15.486	***			5.731	1.217	0.918	0.773	30.795	***
It makes sense to use the Front-Of-Pack label for food purchase	5.820	1.090	0.917	0.770	14.204	***			5.545	1.292	0.884	0.701	28.916	***
		0.000
I will use the Front-Of-Pack label for food purchase in the future	5.580	1.315	0.942	0.480	5.850	***	0.810	0.681	5.209	1.453	0.942	0.480	0.532	***	0.842	0.746
I will recommend using Front-Of-Pack label for food purchase to my friends	4.790	1.597	0.736	0.480	17.952	***			4.579	1.584	0.736	0.480	0.532	***

Table 3b. Model assessment – discriminant validity.

	UK (n = 800)				France (n = 673)
	Perceived usefulness (PU)	Perceived ease of use (PEOU)	Attitude towards using (ATT)	Behavioural Intention (BI)	PU	PEOU	Attitude towards using (ATT)	BI
PU	0.771				0.756
PEOU	0.588	0.832			0.529	0.734
ATT	0.676	0.690	0.828		0.713	0.652	0.816
BI	0.690	0.555	0.825	0.681	0.798	0.520	0.768	0.746

Figure 1. Basic FOPAM model.

Figure 2. Structural model – basic FOPAM.

Table 4a. Model assessment – convergent validity.

Construct(s)	Item(s)	MTL (n = 318)						Nutri-Score (n = 303)						NutrInform Battery (n = 319)
		CFA l oading	SMC	t value	p	α	AVE	CFA loading	SMC	t value	p	α	AVE	CFA loading	SMC	t value	p	α	AVE
Perceived Usefulness (PU)	Food Front-Of-Pack label give (will give) me access to useful food purchase information	0.866	0.751	19,269	***	0.934	0.783	0.872	0.761	19,080	***	0.945	0.815	0.817	0.670	17,507	***	0.911	0.871
	Food Front-Of-Pack label are (will be) very beneficial to me	0.937	0.878	22,046	***			0.934	0.872	21,455	***			0.862	0.742	19,048	***
	Using Food Front-Of-Pack label improves my food purchase	0.873	0.761	19,523	***			0.909	0.825	20,445	***			0.884	0.784	19,845	***
	Using Food Front-Of-Pack label gives me greater control over my food purchase	0.862	0.745	19,116	***			0.896	0.804	19,975	***			0.828	0.690	17,896	***
Perceived Ease of Use (PEOU)	My interaction with the Food Front-Of-Pack label is easy for me to understand	0.879	0.773	19,761	***	0.942	0.846	0.865	0.748	18,611	***	0.925	0.808	0.909	0.829	20,994	***	0.946	0.856
	Overall, I find the Food Front-Of-Pack label easy to use	0.952	0.905	22,609	***			0.920	0.847	20,589	***			0.951	0.908	22,724	***
	It is easy to learn how to use Food Front-Of-Pack label for food purchase	0.927	0.860	21,610	***			0.911	0.829	20,246	***			0.912	0.834	21,112	***
Attitude towards using (ATT)	I am positive about the Front-Of-Pack label t for food purchase	0.936	0.874	22,112	***	0.957	0.882	0.930	0.928	21,354	***	0.959	0.890	0.925	0.926	21,703	***	0.953	0.873
	The use of the Front-Of-Pack label for food purchase is a good idea	0.947	0.895	22,606	***			0.959	0.957	22,607	***			0.934	0.935	22,112	***
	It makes sense to use the Front-Of-Pack label for food purchase	0.936	0.875	22,105	***			0.942	0.941	21,872	***			0.941	0.943	22,403	***
Behavioural Intention (BI)	I will use the Front-Of-Pack label for food purchase in the future	0.961	0.906	22,530	***	0.895	0.816	0.935	0.820	21,348	***	0.915	0.844	0.938	0.763	21,682	***	0.901	0.821
	I will recommend using Front-Of-Pack label for food purchase to my friends	0.844	0.725	18,313	***			0.903	0.869	20,111	***			0.874	0.588	19,221	***

Table 4b. Model assessment – discriminant validity.

	MTL (n = 318)				Nutri-Score (n = 303)				NutrInform Battery (n = 319)
	Perceived usefulness (PU)	Perceived ease of use (PEOU)	Attitude towards using (ATT)	Behavioural Intention (BI)	PU	PEOU	ATT	BI	PU	PEOU	ATT	BI
PU	0.783				0.815				0.871
PEOU	0.698	0.846			0.650	0.808			0.727	0.856
ATT	0.750	0.762	0.882		0.890	0.686	0.890		0.853	0.757	0.873
BI	0.721	0.650	0.880	0.816	0.892	0.643	0.835	0.844	0.831	0.642	0.858	0.821

Table 5. Model comparisons.

Model	χ^2	Df	CFI	RMSEA (95% CI)	ΔCFI
Unconstrained	4,74,073	150	0.975	0.048 (0.043–0.053)	<0.01
Measurement weights	5,09,993	166	0.973	0.047 (0.042–0.052)	<0.01
Structural weights	5,25,760	174	0.973	0.046 (0.042–0.051)	<0.01
Structural covariances	5,36,708	176	0.972	0.047 (0.042–0.051)	<0.01
Structural residuals	5,53,652	182	0.971	0.047 (0.042–0.051)	<0.01
Measurement residuals	5,98,354	206	0.970	0.045 (0.041–0.049)	<0.01