The CCHS 2015 is a cross-sectional survey in which the Canadian population was surveyed from January 2, 2015 to December 31, 2015 . The survey design comprised samples of people according to 12 DRI categories (Age-Sex Dietary Reference Intake). CCHS 2015 was a 24-hour voluntary nutritional recall survey conducted using a modified 5-step automated multi-pass method (AMPM) developed by the U.S. Department of Agriculture and adapted for the Canadian population. Respondents performed a 24-hour nutritional recall and provided additional information on demographics and lifestyle characteristics. The total sample size of the survey was n = 20,487 people with a response rate of 61.6% . After the 24-hour nutritional callback, 35% of respondents were asked to call back on the second day of the week within 3 to 10 days of the first interview.
The survey respondents were> 1 year of age in the 10 provinces of Canada, excluding those living in the following areas: territories, reservations, Aboriginal settlements, full-time members of the Canadian armed forces, and institutionalized individuals . Results from pregnant and lactating women, infants, and those with invalid nutritional recalls (as defined by Statistics Canada) were excluded from this study. This study examined the nutritional quality of foods consumed from individual 24-hour nutritional recalls for boys and girls between the ages of 2 and 18 (n = 4642).
Classification of foods in the 24-hour nutritional recall according to HCST
The foods reported in the 24-hour nutritional recall were categorized and their nutritional composition was determined using the 2015 Canadian Nutrient File (CNF), which contained information on 5690 commonly consumed Canadian foods [11, 12]. Health Canada and the Public Health Agency of Canada developed the CNF / CFG classification, which enables CNF food codes to be linked to four CFG food groups and 21 subgroups according to the 2007 Canadian Food Guide [12, 13]. Foods in CCHS 2015 were categorized into Canada’s Food Guide subgroups and graded according to set thresholds for sodium, saturated fats, total fats and sugars [8, 9, 13]. These thresholds were derived from thresholds used to provide information on nutrient content, DRI and nutritional standards for food in schools .
Exact methods that Health Canada uses to classify foods into animal groups are described elsewhere [8, 9]. In short, lower thresholds for fat and sodium were based on nutritional information for amounts commonly consumed in one session, known as the reference intake (RA). . Level 1 foods must not exceed any of the lower threshold values: ≤ 3 g / RA fat, ≤ 140 mg / RA sodium and ≤ 6 g / RA sugar . Since there is no daily value (DV) for sugar, the upper and lower threshold values for sugar were determined from the recommendation of the Institute of Medicine (IOM). . The 15% DV of sodium (> 360 mg / RA), total fats (> 10 g / RA) and saturated fats (> 2 g / RA) and for sugar (> 19 g) were set as upper thresholds . Tier 2 foods can exceed one or two lower thresholds, but not upper thresholds. Tier 3 foods are foods with a nutrient content above all lower thresholds (i.e. sodium, sugar, and total fat) and can exceed an upper threshold. Tier 4 represents foods that exceed ≥2 upper threshold values. However, foods that belong to the meat and alternative and milk and alternative categories were given special consideration as they naturally have a higher content of saturated fat . Additional adjustments for food based on directions from CFG can be found in HCST .
With the CNF / CFG classification system, 9 food groups could not be classified according to levels 1–4 . From these groups, 5 categories of foods were grouped as “other foods”, which are foods that were not recommended in the 2007 Canadian Food Guide. These groups are: 1) saturated and / or trans fats and oils; 2) high-fat and high-sugar foods like candies, chocolates, and syrups; 3) high calorie drinks ≥ 40 kcal / 100 g; 4) low-calorie drinks <40 kcal / 100 g (without water); and 5) alcoholic beverages [8, 13].
The analyzes were carried out using the Statistical Analysis Software (SAS) version 9.4 (SAS Institute Inc., Cary, NC, USA). A 500-repeat bootstrap balanced replication was used to estimate population parameters, ie, confidence intervals, standard errors, and coefficients of variation. The survey weights supplied with the master files were used for all persons between the ages of 2 and 18 to ensure that the samples from CCHS 2015 remained nationally representative . Food intake was rated by DRI age and sex groups and adjusted for additional lifestyle measures, including smoking, physical activity, and body mass index (BMI). The BMI was determined using the measured height and weight, and the limits for BMI categorization were derived based on the WHO BMI growth curves . PROC SURVEYREG and PROC SURVEYLOGISTIC were used for continuous (e.g. portions of fruit and vegetables) or for categorical (e.g. lifestyle measures) analyzes, whereby the energy intake, age and gender were adjusted if necessary. Results with a two-sided p-value ≤ 0.05 were reported as statistically significant.
Identification of implausible reporters
Studies with the CCHS 2015 identified a large percentage of underreporting [14, 15]. Underreporting is most common in many socially undesirable foods or foods high in fat and sugar [14,15,16]. Following previous publications, this study identified individuals as sub-reporters, plausible reporters and over-reporters based on a comparison of their estimated energy requirements (EER) with total energy consumption (EER: TEE). [11, 16, 17]. The Institute of Medicine (IOM) developed the EER equation taking into account age, gender, BMI, and physical activity . For children under the age of 12, sub-reporters were rated with a Reported Energy Intake (EI).< 74% of the EER, and over-reporters >135% of their EER . For children ≥ 12 years of age, sub-reporters were found to have an EER of less than 70% of the reported values and over-reporters had an EI of greater than 142% of the EER . If children did not have a reported physical activity level (PAL), they were classified as “little active” (< 14 years) and “sedentary” (>14 years), based on findings by Garriguet et al. [11, 15, 17].
All researchers were given goodwill status under the Government Security Policy and passed a security clearance by the Royal Ontario Mounted Police, as required by the Statistics Canada Act. Data analysis was conducted at Statistics Canada’s Toronto, Ontario Research Data Center (RDC), in accordance with survey guidelines and procedures. In order to protect the confidentiality of the respondents, the RDC analysts have reviewed and published the data contained in this manuscript to ensure that the guidelines developed by Statistics Canada are followed. The data presented in this study have been completed as secondary analyzes only and all information provided has been de-identified and did not require institutional REB approval.