Table 1.

Overview of the classification of CAI implemented in the included studies based on the TIPPME typology^(8,9)

Intervention class	Intervention type	Definition	Examples	Studies/examples
Primarily alter properties of product or related object	Functionality/ Functional design	physical changes of equipment or products that change how they work	Shape/type/size of eating/drinking utensils, e.g. easier to open, pour or access	29,30
	Information/Labelling	Changing words, symbols or pictures on product or related objects that convey information about the product or object	• Nutritional labels about nutrients, calories • Traffic lights, health warnings • Fruit/vegetables with nice and interesting names	19,21–26,28–32
	Presentation	Sensory quality and/or visual design of product or its packaging is altered	Way food is arranged, cut, shaped, e.g. see-through containers, pre-sliced food, fruit/vegetables in nice bowls/containers	20,23,25,26,28,30–32
	Sizing *	Size or quantity of product or related object is changed	• Package, portion size • Size of product, e.g. smaller plates	–
Primarily alter placement of product or related objects	Availability	Adding behavioural options to environment with previous potential behaviour still available	Increasing available healthy food option, e.g. more healthy items in vending machines, greater variety of fruit/vegetables in cafeteria	25,27–32
	Position/ Proximity	Accessibility, visibility, proximity of product is altered thus reducing effort for choosing healthier options by making them more salient	• Decreasing distance of products from routes of passage, e.g. fruit/vegetables next to cash register • Placing certain products less prominently • Changing item position on menu	23,25–28,30–32
Alter both properties and placement of product or related objects	Priming	Placement of stimuli within micro-environment to influence via the activation of a semantic relationship or associative process	• Placing decorative objects within a lunchroom or cafeteria	25,30
	Prompting	Explicit verbal, visual, numeric information to promote awareness, more general motivational prompting	• Motivational prompts, e.g. footsteps, posters signs • Promotional signs, e.g. ‘Eat more fruit!’	23–25,30

^*None of the studies matching the inclusion criteria for this review implemented this intervention type.