Table 1.
Assessment of potential mediators
| Concept | Items | Answer categories | α |
|---|---|---|---|
| Individual cognitions | |||
| Attitude towards consuming 200 grams of vegetables a daya | I think eating 200 grams of vegetables per day is … | Very unhealthy (1) – very healthy (5) | 0.75 |
| Very unimportant (1) – very important (5) | |||
| Very disgusting (1) – very delicious (5) | |||
| Perception of vegetables as being expensivea | I think eating 200 grams of vegetables per day is … | Very expensive (1) – very cheap (5) | N.A. |
| Self-efficacya | Do you think you can eat 200 grams of vegetables per day in the next 6 months if you really want to? | Definitely not (1) – definitely (5) | 0.73 |
| How difficult or easy do you think it is to eat 200 grams of vegetables each day in the next 6 months? | Very difficult (1) – very easy (5) | ||
| Subjective norma | Most people who are important to me… | Definitely not (1) – definitely (5) | 0.77 |
| … Think I should eat 200 grams of vegetables each day | |||
| … Eat 200 grams of vegetables each day | |||
| Intentiona | Do you intend to eat 200 grams of vegetables a day? | Definitely not (1) – definitely (5) | N.A. |
| Self-regulation concepts | |||
| General self-regulationa | When I have a goal, I can usually plan how to reach it | Definitely not (1) – definitely (5) | 0.79 |
| I give up quickly (reversed) | |||
| I have trouble to make plans that help me to reach my goals (reversed) | |||
| I have a hard time setting goals for myself (reversed) | |||
| I set goals for myself and keep track of my progress | |||
| If I try to change something, I pay attention on how I am doing | |||
| Action planningb | I have a clear plan for… | Completely disagree (1) – completely agree (4) | 0.91 |
| … When I am going to eat more vegetables | |||
| … Which kinds of vegetables I am going to eat more | |||
| … How much vegetables I am going to eat more | |||
| Coping planningb | I have a clear plan for… | Completely disagree (1) – completely agree (4) | 0.92 |
| … What I am going to do when something interferes with my plans to eat more vegetables | |||
| … What I am going to do in situations in which it can be more difficult to eat more vegetables | |||
| Environmental-level factors | |||
| Perception of availability in supermarketa | In the store where I usually do my shopping, there is a sufficient amount of vegetables available | Completely disagree (1) – completely agree (5) | N.A. |
| Availability of vegetables at homea | How often do you have vegetables available at home? | Never (1) – always (5) | N.A. |
α = Cronbach’s alpha.
aMeasured on a 5-point scale (ranging from 1 to 5); bMeasured on a 4-point scale (ranging from 1 to 4).