Table 1 Description of survey items for potential personal, social-environmental and physical-environmental correlates of weight status

Self-care related to healthy eating

1. "I often feel guilty preparing healthy food when my family would prefer to eat other kinds of foods." 5 responses ranging from "strongly disagree" to "strongly agree." Mean: 2.0 ± 1.0; range: 1-5.

2. "My family's food preferences usually take priority over my own food preferences." 5 responses ranging from "strongly disagree" to "strongly agree." Mean: 2.8 ± 1.2; range: 1-5.

3. "I make time to eat healthy foods even when I am busy looking after my family." 5 responses ranging from "strongly disagree" to "strongly agree." Mean: 3.6 ± 1.0; range: 1-5.

Self-care related to physical activity

1. "I often feel guilty doing physical activity when I have family commitments." 5 responses ranging from "strongly disagree" to "strongly agree." Mean: 3.2 ± 1.2; range: 1-5.

2. "My family commitments usually take priority over my physical activity." 5 responses ranging from "strongly disagree" to "strongly agree." Mean: 3.9 ± 1.1; range: 1-5.

3. "I make time for physical activity even when I am busy with family commitments." 5 responses ranging from "strongly disagree" to "strongly agree." Mean: 2.8 ± 1.2; range: 1-5.

SOCIAL ENVIRONMENTAL

Family support for healthy eating

1. "During the past year, how often did members of your family eat healthy low-fat foods with you?" 5 responses ranging from "never" to "very often." Mean: 3.9 ± 1.1; range: 1-5.

2. "During the past year, how often did members of your family encourage you to eat healthy low-fat foods?" 5 responses ranging from "never" to "very often." Mean: 3.1 ± 1.3; range: 1-5.

3. "During the past year, how often did members of your family discourage you from eating unhealthy foods?" 5 responses ranging from "never" to "very often." Mean: 2.6 ± 1.3; range: 1-5.

Family or friend support for physical activity

1. "During past year, how often did family members do physical activity with you?" 5 responses ranging from "never" to "very often." Mean: 2.9 ± 1.3; range: 1-5.

2. "During past year, how often did family members encourage you to be physically active?" 5 responses ranging from "never" to "very often." Mean: 3.1 ± 1.3; range: 1-5.

3. "During past year, how often did family members discourage you from sitting around too much?" 5 responses ranging from "never" to "very often." Mean: 2.0 ± 1.2; range: 1-5.

4. "If you wanted to do physical activity without your children, do you have access to childcare either at a childcare centre, a partner/family member or a friend?" 3 responses: "yes", "no" and "not applicable" (i.e., I do not do physical activity at all/I would not do physical activity without my children). Distribution: "yes" (69.9%), "no" (20.1%), "not applicable" (10.0%).

Frequency of family meals

1. "How often do you usually eat dinner together with your family?" 6 response options were collapsed into three categories: "≤ 3 times/week" (rarely/never, less than once a week, about 1-3 times a week), "about 4-6 times/week" (about 4-6 times a week), and "daily" (everyday). Distribution: "≤ 3 times/week" (14.3%), "about 4-6 times/week" (29.9%), and "daily" (55.8%).

Children's influence

1. "I like to eat fruit because my children like to eat them." 7 response options were collapsed into 2 categories: "agree" (strongly agree, agree), "other" (neither agree nor disagree, disagree, strongly disagree, I don't eat fruit, not applicable). Distribution: "agree" (79.6%), "other" (20.4%).

2. "I like to eat vegetables because my children like to eat them." 7 response options were collapsed into 2 categories: "agree" (strongly agree, agree), "other" (neither agree nor disagree, disagree, strongly disagree, I don't eat fruit, not applicable). Distribution: "agree" (65.1%), "other" (34.9%).

PHYSICAL ENVIRONMENTAL

Home food availability

1. "About how often are fruits available in your home?" 4 response options were collapsed into 2 categories: "always" (always), "other" (usually, sometimes, never). Distribution: "always" (80.5%), "other" (19.5%).

2. "About how often are vegetables available in your home?" 4 response options were collapsed into 2 categories: "always" (always), "other" (usually, sometimes, never). Distribution: "always" (88.7%), "other" (11.3%).

3. "About how often are these foods available in your home?... (a) cakes/doughnuts/biscuits, (b) potato chips or other salty snack foods, (c) chocolate or other lollies." 3 item scale, How often are energy-dense snacks available in home?, with response options ranging from "never" to "always". Cronbach's alpha = 0.68. Mean: 7.3 ± 1.7; range: 3-12.

4. "About how often are these foods available in your home?... (a) fruit juice, (b) soft drink, (c) sports drinks or energy drinks." 3 item scale, How often are energy-dense snacks available in home?, with response options ranging from "never" to "always". Cronbach's alpha = 0.44. Mean: 6.8 ± 1.8; range: 3-12.