Table 3 Matrix for parents/caregivers at the interpersonal level of the ToyBox-study intervention

PO.1. Parents/caregivers limit preschoolers’ screen viewing activities to one hour per day.

SE.1.a. Parents/caregivers express confidence that they can use different strategies to limit screen viewing activities even when their child wants to continue doing screen viewing activities.

K.1.a. Parents/caregivers know that it is recommended to limit screen activities of their child to one hour per day.

A.1. Parents/caregivers express positive feelings about the benefits that limiting the screen viewing activities one hour per day by using different strategies has for their child.

H1.a. Parents/caregivers plan no or only a limited amount of screen viewing activities of their child in their daily routine.

SE.1.b. Parents/caregivers express confidence that they can use different strategies to limit screen viewing activities even when their child is nagging.

K.1.b. Parents/caregivers list different strategies to limit screen viewing activities.

H.1.b. Parents/caregivers only turn on the TV after a certain time or at a certain moment (e.g., at 7 pm).

H.1.c. Parents/caregivers turn off the TV after a certain program or show or after a certain time.

PO.2. Parents/caregivers motivate (verbally) their children to do other activities instead of screen viewing activities.

SE.2. Parents/caregivers express confidence that they can motivate their child to do other activities instead of screen viewing activities even when their child is nagging.

K.2. Parents/caregivers know how to motivate their child to do other activities instead of screen viewing activities (e.g., tips, tricks).

A.2. Parents/caregivers express positive feelings about the benefits that doing other activities instead of screen viewing activities has for their child.

SI.2. Parents/caregivers indicate that they are able to motivate their child to do other activities instead of screen viewing activities even when their colleagues/ friends/ neighbours don’t motivate their own child.

PO.3. Parents/caregivers do other activities together with their child instead of screen viewing activities.

SE.3. Parents/caregivers express confidence that they can do activities with their child which are not screen viewing activities even when their child only wants to do screen viewing activities.

K.3. Parents/caregivers list activities that can be done instead of screen viewing activities (e.g., tips, tricks, …).

A.3. Parents/caregivers express positive feelings about the benefits that doing other activities together with their child instead of screen viewing activities has for their child.

H.3. Parents/caregivers plan to do other activities together with their child before they turn on the TV at a certain time.

PO.4. Parents/caregivers are a role model for their children and limit their own time sitting down.

SE.4.a. Parents/caregivers express confidence that they can be a role model for their child, even when they had a rough day.

K.4. Parents/caregivers know that being a role model for their child and limit their own time sitting down, encourages their child to also limit his/her time sitting down because they will copy this behavior.

A.4. Parents/caregivers express positive feelings about the benefits of being a role model for their children has for their child because the child will copy this behavior and therefore limit the time sitting down.

H.4. Parents/caregivers change their own habit and turn of the TV if they are together with their child.

SE.4.b. Parents/caregivers express confidence that they can be a role model for their child, even when they are tired or they are not in the mood.

SE.4.c. Parents/caregivers express confidence that they can be a role model for their child.