From: Correlates of objectively measured sedentary time and self-reported screen time in Canadian children
Variable | Measurement method | Use in analysis |
---|---|---|
Anthropometric | ||
Sex | Parent-report: Demographic and Family History Questionnaire | Binary variable: male, female (used as a covariate) |
BMI | Directly measured height and weight, calculated using CDC cut-points [23] | Ordered categorical: underweight, normal weight, overweight, obese |
Percent body fat | Directly measured using Tanita | Continuous |
Waist circumference | Directly measured by ISCOLE researcher | Continuous |
Child ethnicity | Parent-report: Demographic and Family History Questionnaire | Categorical: white, African American, Asian, First Nations, East Indian, don’t know, other (used as a covariate) |
Behavioural characteristics | ||
Healthy and unhealthy eating scores | Child-report food frequency questionnaire: ISCOLE Diet and Lifestyle Questionnaire | Continuous: Continuous: obtained from a principal component analysis derived from a 23-item food frequency questionnaire |
Breakfast consumption (weekend, and weekday) | Child-report: ISCOLE Diet and Lifestyle Questionnaire | Re-coded as dichotomous: those who ate breakfast at least once per weekday (versus never) and those who at breakfast at least weekend day (versus never). |
Commute to school (main part of journey) | Child-report: ISCOLE Diet and Lifestyle Questionnaire | Re-coded as dichotomous: active (walking, bicycle/rollerblade/skateboard/scooter, other), and inactive (bus/train/tram/underground/boat, car/motorcycle/moped) |
Sleep (in the past week) | Child-report: ISCOLE Diet and Lifestyle Questionnaire | Categorical: Sleep quality (4 responses: very good, fairly good, fairly bad, very bad), sleep quantity (4 responses: very good, fairly good, fairly bad, very bad). Re-coded for analysis, collapsing very good and fairly good categories, and fairly bad and very bad categories for both sleep quality and sleep quantity. |
Physical activity | Child-report: ISCOLE Diet and Lifestyle Questionnaire | Categorical: 8 responses (0Â days, 1Â day, 2Â days, 3Â days, 4Â days, 5Â days, 6Â days, 7Â days). Was included in the model re-coded as those active more and less than 6Â days in the past week. |
Accelerometer measured minutes per day of LPA and MVPA | Accelerometer: time spent at different PA intensities using Evensen cut-points [19] | |
Family situation | ||
Number of siblings | Parent-report: Demographic and Family History Questionnaire | Continuous (used as a covariate) |
Parental BMI | Parent-report: Demographic and Family History Questionnaire | Re-coded as dichotomous: normal weight, or overweight/obese |
Parental education | Parent-report: Demographic and Family History Questionnaire | Re-coded as dichotomous: ≤high school, and high school or higher |
Combined household income | Parent-report: Demographic and Family History Questionnaire | Ordered categorical: 8 options ranging from < $14,999, to > $140,000 or more (used as covariate). In the model, income was re-coded as above/below mean category. |
Home environment | ||
Number of TVs in home | Parent report: ISCOLE neighbourhood and home environment questionnaire | Re-coded as dichotomous: ≤1, and ≥2 |
TV/electronics in bedroom | Child-report: ISCOLE Diet and Lifestyle Questionnaire | Binary response: yes/no |
Parent report: ISCOLE neighbourhood and home environment questionnaire | ||
Automobile ownership | Parent report: ISCOLE neighbourhood and home environment questionnaire | Continous: number of working automobiles owned per household. Re-coded as dichotomous: <2 and ≥2. |