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Relationship between dietary diversity and nutritional adequacy in Iranian children aged 24–59 months: a study protocol | BMC Nutrition

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Development of dietary diversity questionnaires

Guided by FAO guidelines for measuring individual dietary diversity [3, 9], a scale item is generated. According to the guidelines, foods are classified into nine groups as shown in Table 1. Food amounts of at least 1 tablespoon (≥ 15 g) are included in the score. Dietary diversity scores are calculated by summing the number of food groups consumed by individual respondents.

Table 1 Food groups for calculating dietary diversity scores

Content validity

Nutritional experts will evaluate the first version of the questionnaire for its relevance, clarity, meaning, and completeness.

predictive validity

Pearson correlation analysis was performed to analyze the correlation between DDS and NAR, mean adequacy ratio (MAR), anthropometric indices (height versus age, weight versus age, BMI z-score versus age), and serum retinol. increase.

sample size

To calculate the sample size, errors in α and β were taken as 5% and 10%, respectively.According to Hatroy [10], the correlation coefficient between MAR and DDS was estimated to be 0.4. The sample size was calculated as her 51 children in each state.

Recruitment/Aptitude Screening

Children aged 24-59 months from 11 states including Sistan-Baloochestan, South Khorasan, Ilam, Kohkiluyeh-Boyerahmad, Khuzestan, Kerman, Hormozgan, Bushehr, Kordestan, North Khorasan, and Tehran are included in this study. Exclusion criteria included reluctance to participate in the study, physical and/or mental retardation, and adherence to special diets. Eligible children are enrolled through random cluster sampling proportional to size. The Iran Statistics Center provides a list of clusters. Ten clusters are randomly selected in each state, including seven urban clusters and three rural clusters. A total of 561 children will be enrolled.

Data collection

We collect information using mobile apps and electronic surveys. General information is obtained using questionnaires. Children’s weight and height are measured using standard methods. A biochemical test will be performed for each child Serum retinol assessment will be performed in the same laboratory using high performance liquid chromatography (HPLC). All parents/carers must sign an informed her consent form after a complete review of the inclusion and exclusion criteria and explanation of the study protocol. The study protocol has been approved by the Ethics Committee of the National Institute of Nutrition and Food Technology, Shahid Beheshti Medical College.

nutritional assessment

The dietary diversity questionnaire is completed by the child’s parent/guardian. A 24-hour food recall will also be performed on his two occasions to assess energy and nutrient intake. The interval between two recalls ranges from 1 day up to 7 days. Consumed foods are first converted to grams and then nutrient and energy content are calculated using Nutritionist-IV software and the United States Department of Agriculture (USDA) Food Composition Tables (FCT). His FCT in Iran is also used in local foods. All stages are performed by an experienced and trained nutritionist.

nutritional adequacy

To estimate nutrient adequacy, nutrient compatibility of energy, protein, and micronutrients (vitamin A, vitamin E, B1, B2, niacin, B6, B12, folic acid, vitamin C, calcium, iron, and zinc) (NAR) is used.Calculated [10]As an overall measure of nutrient adequacy, the MAR is calculated. This is the sum of each NAR (rounded down at 100%) divided by the number of nutrients (excluding energy and protein). [10]A value of 100% is ideal for both NAR and MAR as it means that the intake is the same as the requirement. Energy, protein, vitamin and mineral requirements for each gender and age group are calculated based on estimated average requirements (EAR). [11,12,13].

data analysis

Data are analyzed using STATA software (version 17; StataCorp).a P. Values ​​< 0.05 are considered statistically significant in all analyses. The WHO Anthro Survey Analyzer is applied to analyze anthropometric data. Data files in comma-delimited format (.csv) are uploaded to the URL: After calculating the DDS, to analyze the correlations between the DDS and NAR, MAR, anthropometric indices (height for age, weight for age, her Z-score for her BMI for age), and serum retinol, Pearson correlation was used. Analysis is done.