Tool Library Tool Information
Validation Information: FFQ (Suihua, North China)
Reproducibility and Relative Validity of a Food Frequency Questionnaire Developed for Female Adolescents in North China
This study aims to evaluate the reproducibility and validity of a food frequency questionnaire (FFQ) developed for female adolescents in the Suihua area of North China. The FFQ was evaluated against the average of 24-hour dietary recalls (24-HRs).
A total of 168 female adolescents aged 12 to 18 completed nine three consecutive 24-HRs (one three consecutive 24 HRs per month) and two FFQs over nine months. The reproducibility of the FFQ was estimated using intraclass correlation coefficients (ICCs), and its relative validity was assessed by comparing it with the 24-HRs. The mean values of the 24-HRs were lower than those of the FFQs, except for protein (in FFQ1) and iron (in FFQ2). The ICCs for all nutrients and food groups in FFQ1 and FFQ2 were moderately correlated (0.4–0.8). However, all the ICCs decreased after adjusting for energy. The weighted κ statistic showed moderate agreement (0.40–0.6) for all nutrients and food groups, except for niacin and calcium, which showed poor agreement (0.35). The relative validity results indicate that the crude Spearman's correlation coefficients of FFQ1 and the 24-HRs ranged from 0.41 (for Vitamin C) to 0.65 (for fruit). The coefficients of each nutrient and food group in FFQ2 and the 24-HRs were higher than those in FFQ1 and the 24-HRs, indicating good correlation. Although all energy-adjusted Spearman's correlation coefficients were lower than the crude coefficients, de-attenuation to correct for intra-individual variability improved the correlation coefficients. The weighted κ coefficients of nutrients and food groups ranged from 0.32 for beans to 0.52 for riboflavin in FFQ1 and the 24-HRs, and 0.32 for Vitamin C to 0.54 for riboflavin in FFQ2 and the 24-HRs.
The FFQ developed for female adolescents in the Suihua area is a reliable and valid instrument for ranking individuals within this study.
Total number of nutrients validated: 13
Not all of the nutrients validated in the validation studies are included in the table below, as statistical data was only selected to be displayed for a number of nutrients, this included:
- Saturated Fat
- Mono-unsaturated Fat
- Poly-unsaturated Fat
- Non‐starch polysaccharides(NSP)
- Folic Acid
- Vitamin B12
- Vitamin C
- Fruit & Vegetables
- Urinary Nitrogen
To find information on the other validated nutrients please read the validation study.
- Macronutrients: 4
- Micronutrients: 9
|Comparator||Lifestage||Sex||Nutrient Measured||Mean Difference||Standard Deviation||Correlation Coefficient||Cohen's Kappa Coefficient||Percentage Agreement||Percentage Agreement Categories||Lower Limits of Agreement||Upper Limits of Agreement|
|24hr recall||Adolescents||Female Only||energy (kcal)||327||340||0.65 (S)||0.41 (W)|
|Protein (g)||11||22||0.59 (S)||0.45 (W)|
|Fat (g)||14||18||0.62 (S)||0.49 (W)|
|Carbohydrates (g)||40||106||0.63 (S)||0.43 (W)|
|Fibre (g)||6||10||0.52 (S)||0.40 (W)|
|Calcium (mg)||121||187||0.64 (S)||0.54 (W)|
|Iron (mg)||-2||5||0.62 (S)||0.48 (W)|
|Zinc||2||4||0.62 (S)||0.46 (W)|
|Retinol (µg)||124||324||0.62 (S)||0.43 (W)|
|Vitamin C (mg)||20||37||0.43 (S)||0.32 (W)|
|Fruit||39||123||0.71 (S)||0.40 (W)|
|Vegetables||49||94||0.57 (S)||0.43 (W)|
Some results have been calculated using statistical techniques based on the published data.
For further information on statistical terms click on Statistical tests used in validation studies
All correlations coefficients in the table are unadjusted unless stated otherwise. For adjusted correlation coefficients and other statistical methods used in the study e.g. paired t-tests, please read the validation articles.
- # Adjusted
- † Energy adjusted.
- ‡ For loge-transformed, energy-adjusted nutrient intakes.
- ^ Adjacent included.
- ᵟ Participants provided identical responses.
- (w) = Weighted.
Xia W, Sun Cailong, Zhang L, Zhang,X, Wang J & Wu, L. Reproducibility and Relative Validity of a Food Frequency Questionnaire Developed for Female Adolescents in Suihua, North China. PlosONE 2011 6(5) 1-7