Reproducibility and validity of a food-frequency questionnaire designed for use in girls age 7 to 12 years

Reproducibility and Validity of a Short Food Frequency Questionnaire for Dietary Assessment in Children Aged 7⁻9 Years in Spain

The purpose of this study was to examine if the short semi-quantitative food frequency questionnaire (FFQ) is a reliable and valid tool to assess the diet of Spanish children aged 7-9 years. We collected data from 156 children of the birth cohort INMA (Infancia y Medio Ambiente (Environment and Childhood)). Children's parents or care-givers completed a 46-item FFQ on two occasions over a 9-12-month period about the children's diet. To explore the reproducibility of the FFQ, the nutrient and food group intake collected from the both FFQs were compared, while validity was examined by contrasting the nutrient values from the FFQs and the average of three 24-hour dietary recalls (24hDRs) taken in this period, and also with the concentration of several vitamins in the blood (carotenoids, vitamin D and α-tocopherol). Pearson and de-attenuated correlation coefficients were calculated. The average correlation coefficients for nutrient intake's reproducibility was 0.41, ranging from 0.25 (calcium) to 0.65 (β-carotene), and for food group intake was 0.45, ranging from 0.18 (cereals) to 0.68 (sweetened beverages). Correlation coefficients slightly improved when we compared energy-adjusted intakes. The average correlation coefficients for validity against 24hDRs was 0.34 for energy-adjusted intakes, and 0.39 when de-attenuation coefficients were used. The validity coefficients against the blood concentrations of vitamins were 0.38 for β-cryptoxanthin, 0.26 for lycopene, 0,23 for α-carotene and 0.15 for β-carotene, all of them statistically significant (p < 0.05). This study suggests that our brief FFQ is a suitable tool for the dietary assessment of a wide range of nutrients and food groups in children 7-9 years, despite the low to moderate reproducibility and validity observed for some nutrients.

Relative Validity of Three Food Frequency Questionnaires for Assessing Dietary Intakes of Guatemalan Schoolchildren

Objective

To determine the relative validity of three food frequency questionnaires (FFQs) compared with results from 24-hour dietary recalls for measuring dietary intakes in Guatemalan schoolchildren.

Design

A cross-sectional study of primary caregivers (mothers or grandmothers) of 6–11 year-old children. Caregivers completed one of three constructed FFQs to measure the child’s dietary consumption in the last week: FFQ1 did not incorporate portion sizes; FFQ2 provided portion sizes; and FFQ3 incorporated pictures of median portion sizes. During the same week, each caregiver also completed three 24-hour dietary recalls. Results from the FFQ were compared with corresponding results from the 24-hour dietary recalls.

Setting

Santa Catarina Pinula, peri-urban Guatemala City.

Subjects

Caregivers (n = 145) of 6–11 year-old children: 46 completed FFQ1, 49 completed FFQ2, and 50 completed FFQ3.

Results

The mean values for all nutrients obtained from the 24-hour dietary recall were lower than for those obtained from the FFQs, excluding folic acid in FFQ3, cholesterol and zinc in FFQ2, and cholesterol, folic acid, magnesium, potassium, sodium, and zinc in FFQ1. Energy-adjusted Pearson correlation coefficients ranged from 0.07 (protein) to 0.54 (cholesterol) for FFQ1 and from 0.05 to 0.74 for FFQ2 and FFQ3. Agreement by both methods (FFQ and 24-hour dietary recalls) of classifying children into the same or adjacent quartiles of energy-adjusted nutrient consumption ranged from 62.0% for cholesterol to 95.9% for vitamin B12 across all three FFQs.

Conclusions

Our FFQs had moderate to good relative validity in measuring energy and nutrient intakes for 6–11 year-old Guatemalan children. More evidence is needed to evaluate their reproducibility and applicability in similar populations.

Is the food frequency questionnaire suitable to assess micronutrient intake adequacy for infants, children and adolescents?

The objective of this study was to review how accurately micronutrient intakes in infants, children, and adolescents were assessed with validated food frequency questionnaires (FFQs) to which study quality criteria had been applied. The methodology and the analysis presented were based on several research activities carried out within the European Micronutrient Recommendation Aligned Network of Excellence. The analysis was limited to vitamin D, vitamin C, vitamin B₁₂, folate, selenium, iron, zinc, iodine, calcium, and copper. A search strategy was defined in MEDLINE and EMBASE literature for studies validating FFQs that estimated intakes of micronutrients being evaluated. Identification of at least three validation studies per micronutrient was required to be included in the analysis. A total score for each nutrient was calculated from the mean of the correlation coefficients weighted by the quality of the study, which included a quality score that was based on sample size, statistics used, data collection procedure, consideration of seasonality and supplement use, an adjustment/weighting of the correlation coefficient according to the quality score, and a rating of the adjusted/weighted correlation. When the mean weighted correlation coefficient was equal to or higher than 0.5, micronutrient intake was considered as adequately estimated. Sufficient validation studies were identified for vitamin C, vitamin D, vitamin B₁₂, iron, zinc, and calcium for infants and pre-school children, and vitamin C, calcium, and iron for older children and adolescents. Results showed that the FFQ was a good instrument for estimating intake of vitamin C, vitamin D, calcium, zinc and iron in infants and pre-school children, and for estimating calcium and vitamin C in children and adolescents.

Dietary assessment methods for micronutrient intake in infants, children and adolescents: a systematic review

A systematic literature search identified studies validating the methodology used for measuring the usual dietary intake in infants, children and adolescents. The quality of each validation study selected was assessed using a European micronutrient Recommendations Aligned-developed scoring system. The validation studies were categorised according to whether the study used a reference method that reflected short-term intake ( < 7 d), long-term intake ( ≥ 7 d) or used biomarkers. A correlation coefficient for each nutrient was calculated from the mean of the correlation coefficients from each study weighted by the quality of the study. Thirty-two articles were included in the present review: validation studies from infants (1–23 months); child preschool (2–5 years); children (6–12 years); adolescents (13–18 years). Validation of FFQ studies in infants and preschool children using a reference method that reflected short-term intake showed good correlations for niacin, thiamin, vitamins B6, D, C, E, riboflavin, Ca, K, Mg, Fe and Zn (with correlations ranging from 0·55 for vitamin E to 0·69 for niacin).Regarding the reference method reflecting short-term intake in children and adolescents, good correlations were seen only for vitamin C (r 0·61) and Ca (r 0·51). Using serum levels of micronutrient demonstrated that the 3 d weighed dietary records was superior to the FFQ as a tool to validate micronutrient intakes. Including supplement users generally improved the correlations between micronutrient intakes estimated by any of the dietary intake methods and respective biochemical indices.

Racial and socioeconomic disparities in nutrition behaviors: targeted interventions needed

OBJECTIVE

To compare dietary knowledge, behaviors and self-efficacy of black middle school students of low socioeconomic status with their white counterparts of higher socioeconomic status.

DESIGN

Cross-sectional, school-based survey.

SETTING

Large metropolitan area in the United States.

PARTICIPANTS

Middle school students (1,208 of low socioeconomic and 978 of higher socioeconomic status).

MAIN OUTCOME MEASURES

Dietary behaviors, dietary knowledge, and dietary self-efficacy were assessed by questionnaire.

ANALYSIS

Differences between black students of low socioeconomic status and white students of higher socioeconomic status in the above variables.

RESULTS

Black students of low socioeconomic status scored significantly lower than did white students of higher socioeconomic status on several of the variables. They were more likely to consume empty calorie food, meat, and fried food and less likely to eat fruit, vegetables, dairy products, and grains; they were less knowledgeable about dietary variables; and they had significantly lower self-efficacy regarding their ability to change dietary habits.

CONCLUSIONS AND IMPLICATIONS

The results of this study suggest that black students of low socioeconomic status should be targeted for early intervention related to dietary behaviors. This age group is amenable to change, and interventions designed specifically for them may result in lifetime reductions in risk of morbidity and mortality.

Food-frequency questionnaires: a review of their design, validation and utilisation

A review of the literature concerning the design, utilisation and validation of food-frequency questionnaires (FFQ) has been carried out using a semi-systematic approach to obtaining, reviewing and extracting data from articles. Databases were searched from 1980 to 1999. The present review identified 227 validation (from 1980 to September 1999) and 164 utilisation (for 1998 only) studies. A number of design issues have been evaluated through the present review. These include: the need to consider how portion sizes have been described, self-defined giving higher mean correlations; how an FFQ was administered, interviewer-administered giving higher mean correlations for some nutrients; how many items to include on an FFQ, those with the largest number of items having higher correlations. Validation techniques were described. Most validation studies involved comparing an FFQ against another dietary assessment method; only 19 % compared an FFQ to a biomarker. Measurement differences were most commonly assessed by correlation coefficients as opposed to other more appropriate methods. Mean correlation coefficients were highest for Ca and fat, and lowest for vitamin A and vegetables. The utilisation studies showed that FFQ were most commonly used in cross-sectional surveys, with ninety-three of the FFQ being designed to be disease-specific. The present review results were presented to a group of experts and a consensus arrived at concerning the development, validation and use of FFQ. Recommendations derived from the consensus arising from the literature review are presented as an appendix to the present paper.

Validity and reliability of a calcium checklist in early elementary-school children

Objective

To create, validate and assess the reliability of a checklist to measure calcium intake in children.

Design

Calcium intakes from a checklist and parent-assisted 24-h dietary recall were compared. Checklist reliability was assessed separately.

Setting

After-school programmes in the United States.

Subjects

Forty-two children (18 males, 24 females, age = 8.0 ± 0.9 years) participated in the validation analysis and 49 children (28 males, 21 females, age = 7.5 ± 0.9 years) in the reliability analysis.

Results

No differences in mean calcium intakes were found by method or gender. The checklist correlated well with recall among girls (r = 0.65, P = 0.01) but not boys (r = −0.33, P = 0.19). Agreement over time was above 80% for most foods.

Conclusion

The calcium checklist is useful for assessing calcium intake among groups of 6–10-year-old children in settings that preclude parental assistance. More research is needed to improve accuracy among boys.

Examining intention to control preschool children's sugar snacking: a study of carers in Uganda

AIM

The aims of this study were to investigate parents' intention to control their children's sugar consumption and whether that behaviour is reported to occur in 3-5-year-old preschool children according to sociodemographics and attitudinal factors derived from the Theory of Planned Behaviour (TPB).

DESIGN

Some 589 children aged 3-5 years (51% boys, response rate = 85%) attending nursery schools in Kampala Central (urban) and Nakawa (suburban), Uganda, were examined clinically for dental caries. A questionnaire to assess sociodemographic factors, sugar intake and the constructs of the TPB was completed by their parents'/caregivers in face-to-face interviews.

RESULTS

Analyses of variance revealed more positive attitudes and stronger intention to control children's intake of sugared snacks in highly as compared to less highly educated parents. Independent of educational level, parents having children with caries perceived themselves to have less control over their child's intake of sugared snacks and perceived them to be more susceptible to tooth decay compared to parents of children without caries. In multiple linear regression, the TPB provided a significant prediction of intention with attitude (b = 0.16, P < 0.001), subjective norms (b = 0.18, P < 0.001) and perceived barriers (b = 0.11, P = 0.01), significant and reported sugar intake with attitudes (b = -0.10, P = 0.02), and perceived susceptibility (b = 16, P < 0.001) all significant.

CONCLUSION

The TPB components predict parental intention to control sugar snacking and whether that behaviour occurs in preschool children. The strengths of parents' attitudes and reported level of child sugar snacking varied between diverse socioeconomic family groups. Implications for oral health education are discussed.

Ratio of omega-6 to omega-3 fatty acids and childhood asthma

Asthma is a leading cause of morbidity for children and is a major public health problem in Australia. Ecological and temporal data suggest that dietary factors may have a role in recent increases in the prevalence of asthma.

AIM

The aim of conducting this study was to investigate whether childhood asthma was associated with the ratio of omega 6 (n-6) to omega 3 (n-3) fatty acids in the diet (n-6:n-3).

METHOD

The Western Australian Pregnancy Cohort Study is a prospective birth cohort of 2602 children. Using a nested case-control cross-sectional study design within this cohort, a group of children were identified as cases with current asthma at 6 or at 8 years of age or as controls with no asthma at 6 or at 8 years. Dietary details including n-6 and n-3 fatty acid intake data were collected by parent response to a questionnaire when the children were 8 years old. Logistical regression was used to compare quartiles of n-6:n-3 intake in cases and controls. Adjustment was made for covariates: gender, gestational age, breastfeeding, older siblings, maternal smoking during pregnancy, maternal age, maternal asthma, child's current age in months, body mass index, total energy intake, and antioxidant intake (vitamins A, C, E, and zinc).

RESULTS

A response rate of 83% was achieved by providing complete data from 335 children [49% cases with current asthma (n = 166), 51% controls (n = 169)]. Following adjustment for covariates the association between the ratio of n-6:n-3 fatty acids and risk for current asthma was statistically significant (p = 0.022).

CONCLUSION

We found evidence for a modulatory effect of the dietary n-6:n-3 fatty acid ratio on the presence of asthma in children. Our results provide evidence that promotion of a diet with increased n-3 fatty acids and reduced n-6 fatty acids to protect children against symptoms of asthma is warranted.

A cohort study of dietary fibre intake and menarche

OBJECTIVE

To evaluate the influence of dietary fibre on menarche in a cohort of pre-menarcheal girls.

DESIGN

Prospective cohort study.

SETTING

Ontario, Canada.

SUBJECTS

Free-living pre-menarcheal girls (n = 637), 6 to 14 years of age.

METHODOLOGY

Information on dietary intake, physical activity and date of menarche was collected at baseline and was updated annually by self-administered questionnaires for three years. Cox proportional hazards models were used to evaluate the association between dietary fibre and menarche, adjusting for age at entry to the study and potential confounders.

RESULTS

A higher intake of energy-adjusted dietary fibre was associated with a lower risk of (i.e. a later age at) menarche (relative hazard 0.54, 95% confidence interval (CI) 0.31-0.94 for highest vs. lowest quartile, P for trend = 0.027). At the fibre component level, a higher intake of energy-adjusted cellulose was associated with a lower risk of menarche (relative hazard 0.45, 95% CI 0.26-0.76, P for trend = 0.009).

CONCLUSIONS

The findings are consistent with the hypothesis that pre-menarcheal dietary intake can influence menarche.

An investigation of the validity and reliability of a food intake questionnaire

AIMS

To evaluate the reliability and criterion validity of a food intake questionnaire (FIQ) designed for use in schoolchildren.

METHODS

Study of reliability: 98 young people aged 13-14 years attending two schools in deprived areas of Liverpool completed the FIQ on three separate occasions over a 3-month period. VALIDITY STUDY: Ninety-six young people (aged 11-13 years) completed the FIQ and 2 weeks later completed a 3-day food diary (with interview).

RESULTS

The FIQ gave consistent response on separate occasions over the 3-month reliability study period. Levels of agreement were consistent between survey combinations. Analysis of variance showed no differences in mean score for food groups between surveys. Pearson correlations for mean scores estimated by separate FIQ ranged from 0.42 for fibre food group to 0.76 for negative marker food group; the majority of the correlations were above 0.5. The data suggested the FIQ should be able to detect a change of +/-10% in eating habits. The validity study provided modest but significant Pearson correlations between energy intake, fat intake as a percentage of energy intake and sugars intake derived from 3-day diaries, and mean scores for the fatty, sugary and negative marker food group assessed by the FIQ.

CONCLUSIONS

The results from both studies provide an indication of the FIQ's reliability, and suggest it has criterion validity for fatty and sugary and negative marker foods.

Validity and reliability of a modified qualitative dietary fat index in low-income, overweight, African American adolescent girls

This study evaluated the validity and reliability of a modified qualitative dietary fat index questionnaire (QFQ) in an adolescent minority population. The QFQ was administered to study participants twice over a 2-week period, and data were compared with mean values from three 24-hour recalls. Fifty-seven low-income, overweight, African American adolescent girls, aged 11 to 17 years, were recruited from 7 public housing developments in Atlanta, Georgia. To determine validity, the total QFQ score was compared with the mean values of total fat, percentage of energy from fat, and total energy from three 24-hour recalls within 2 weeks of first administration of the QFQ. Reliability was tested in a subsample (n = 22) by comparing total QFQ scores administered 2 weeks apart. Total fat was significantly correlated (r = 0.31, P < .05) with the QFQ score. Total energy (r = 20.23) and percentage of energy from fat (r = -0.23) were not significantly correlated with the QFQ score. The test-retest QFQ scores were significantly correlated (r = 0.54, P < .01). The data suggest that additional modifications are needed to make the QFQ more appropriate for low-income, over-weight, African American adolescent girls.

Development of a modified picture-sort food frequency questionnaire administered to low-income, overweight, African-American adolescent girls

There is essentially no ideal method of dietary assessment. Physiologic methods (i.e., doubly labeled water) probably come closest, but high cost, participant burden, and limited information limit their use. Furthermore, most dietary assessment methods have been designed for and tested in white adults. Very few have been designed for and tested in African-American adolescents. This study examined validity and reliability of a modified picture-sort food frequency questionnaire (FFQ) administered to 22 low-income, overweight, African-American adolescent girls, aged 11 to 17 years. The FFQ was administered to subjects twice during a 2-week period, and evaluated using the mean values of three 24-hour recalls. The natural log-transformed energy-adjusted, deattenuated correlation coefficients between the second FFQ and the mean from 3 recalls exceeded 0.50 for most nutrients, ranging from 0.32 (protein) to 0.87 (saturated fat). The energy and nutrient values from the first FFQ were greater than those from the second FFQ. Most correlation coefficients for the test-retest reliability of the FFQ were not significant. We conclude that although larger samples are needed to generalize results, the picture-sort dietary assessment method appears to be promising and merits further research.