Table 4.
Agreement of classification in test and retest of the SF-FFQ4PolishChildren questionnaire (%).
| Variables | Cat. 1 | Children Aged 6–10 Years | Adolescents Aged 11–15 years | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Parent (Test–Retest) | Adolescent (Test–Retest) | Adolescent (Test) & Parent (TestP) | |||||||||||
| n | Total Agreement | Misclassification | n | Total Agreement | Misclassification | n | Total Agreement | Misclassification | |||||
| ±1 Cat. | ±2 Cat. or More | ±1 Cat. | ±2 Cat. or More | ±1 Cat. | ±2 Cat. or More | ||||||||
| Nutrition knowledge level 2 | 3 | 432 | 85.0 | 14.8 | 0.2 | 615 | 72.7 | 27.3 | 0.0 | 628 | NA | ||
| Dietary habits | |||||||||||||
| Breakfast | 4 | 436 | 88.8 | 7.8 | 3.4 | 629 | 77.3 | 17.8 | 4.9 | 628 | 80.3 | 12.6 | 7.2 |
| Meal at school | 4 | 435 | 95.4 | 3.9 | 0.7 | 629 | 79.8 | 16.2 | 4.0 | 626 | 81.6 | 14.7 | 3.7 |
| Dairy products | 7 | 435 | 68.0 | 24.8 | 7.1 | 630 | 51.3 | 33.8 | 14.9 | 627 | 44.3 | 34.4 | 21.2 |
| Fish | 7 | 436 | 77.1 | 19.3 | 3.7 | 628 | 57.3 | 31.5 | 11.1 | 627 | 50.9 | 37.0 | 12.1 |
| Fast food | 7 | 436 | 80.7 | 16.7 | 2.5 | 628 | 61.8 | 30.9 | 7.3 | 627 | 58.9 | 27.8 | 13.4 |
| Sweetened soft drinks | 7 | 436 | 64.9 | 23.4 | 11.7 | 628 | 50.8 | 26.8 | 22.5 | 628 | 41.1 | 32.0 | 26.9 |
| Fruit or mixed fruit and vegetable juices | 7 | 434 | 59.0 | 26.7 | 14.3 | 629 | 42.9 | 33.7 | 23.4 | 628 | 43.5 | 30.7 | 25.8 |
| Energy drinks | 7 | 437 | 98.4 | 1.4 | 0.2 | 629 | 80.1 | 12.4 | 7.5 | 628 | 83.9 | 8.4 | 7.6 |
| Vegetables | 7 | 437 | 66.6 | 19.9 | 13.5 | 628 | 45.9 | 32.3 | 21.8 | 627 | 46.3 | 26.3 | 27.4 |
| Fruit | 7 | 432 | 66.2 | 22.7 | 11.1 | 629 | 44.5 | 34.0 | 21.5 | 627 | 42.9 | 28.9 | 28.2 |
| Sweets | 7 | 433 | 70.2 | 21.5 | 8.3 | 629 | 49.4 | 36.1 | 14.5 | 628 | 43.8 | 31.1 | 25.2 |
| pHDI | 3 | 430 | 79.5 | 20.5 | 0 | 625 | 75.8 | 23.5 | 0.6 | 622 | 69.0 | 30.5 | 0.5 |
| nHDI | 3 | 432 | 96.8 | 3.2 | 0.0 | 625 | 92.0 | 7.7 | 0.3 | 623 | 92.3 | 7.7 | 0.0 |
| Active/sedentary lifestyle | |||||||||||||
| Screen time | 6 | 434 | 86.9 | 11.5 | 1.6 | 623 | 64.8 | 24.9 | 10.3 | 625 | 60.0 | 29.9 | 10.1 |
| Physical activity level | 3 | 432 | 86.3 | 13.4 | 0.2 | 622 | 74.8 | 24.6 | 0.6 | 626 | 65.3 | 32.1 | 2.6 |
| Physical activity at school | 3 | 435 | 84.4 | 14.5 | 1.1 | 622 | 74.6 | 24.0 | 1.4 | 627 | 64.6 | 29.8 | 5.6 |
| Physical activity at leisure time | 3 | 432 | 83.8 | 15.3 | 0.9 | 623 | 71.3 | 27.0 | 1.8 | 626 | 59.9 | 37.9 | 2.2 |
| FAS components | |||||||||||||
| How many computers, laptops, or tablets does your family own? | 4 | 433 | 87.1 | 11.5 | 1.4 | 626 | 83.7 | 15.2 | 1.1 | 623 | 75.6 | 20.5 | 3.9 |
| Does your family own a car, van, or truck? | 3 | 433 | 91.9 | 7.6 | 0.5 | 627 | 86.3 | 11.5 | 2.2 | 622 | 83.6 | 13.0 | 3.4 |
| Does your family have a dishwasher? | 2 | 435 | 97.5 | 2.5 | 625 | 95.8 | 4.2 | 622 | 95.5 | 4.5 | |||
| Do you have your own bedroom? | 2 | 435 | 96.1 | 3.9 | 622 | 95.8 | 4.2 | 620 | 92.9 | 7.1 | |||
| How many bathrooms (room with a bath or shower) are in your home? | 4 | 434 | 95.2 | 4.1 | 0.7 | 628 | 90.9 | 7.5 | 1.6 | 624 | 89.4 | 9.9 | 0.6 |
| Does your home have an outdoor space attached (e.g., garden)? | 2 | 432 | 95.1 | 4.9 | 625 | 95.2 | 4.8 | 622 | 95.2 | 4.8 | |||
| BMI-for-age | 3 | 407 | 89.4 | 10.6 | 0.0 | 583 | 90.2 | 9.6 | 0.2 | 585 | 92.1 | 7.7 | 0.2 |
1 number of categories in the question; cat.—categories; nutrition knowledge level—based on 18 questions and assessed in three categories: Low (5 points), moderate (12 points), high (13–18 points) [22]; 2 in a group of 6–10-year-old children, nutrition knowledge was assessed in their parents; pHDI—a pro-healthy diet index composed of four questions (dairy products, fish, vegetables, fruit) and assessed in three categories: Low (0–33.32% points), moderate (33.33–66.65% points), high (66.6–100% points) [22]; nHDI—a non-healthy diet index composed of four questions (fast food, sweetened soft drinks, energy drinks, sweets) and assessed in three categories: Low (0–33.32% points), moderate (33.33–66.65% points), high (66.66–100% points) [22]; physical activity level—based on two questions: Physical activity at school and physical activity at leisure time and assessed in three categories: Low (0–1 points), moderate (2–4 points), high (5 points) [22]; FAS components—six questions of the Family Affluence Scale [26]; BMI-for-age—the age-sex-specific body mass index calculated using self-reported height and weight and assessed in three categories [27]; NA—not applied.