Log in Register

Tool Library Tool Information Best Practice Guidelines – Evaluation Checklist (opens new tab)

Validation Information: Food4Me

Fallaize 2014

Online Dietary Intake Estimation: Reproducibility and Validity of the Food4Me Food Frequency Questionnaire Against a 4-Day Weighed Food Record

Background: Advances in nutritional assessment are continuing to embrace developments in computer technology. The online Food4Me food frequency questionnaire (FFQ) was created as an electronic system for the collection of nutrient intake data. To ensure its accuracy in assessing both nutrient and food group intake, further validation against data obtained using a reliable, but independent, instrument and assessment of its reproducibility are required.

Objective: The aim was to assess the reproducibility and validity of the Food4Me FFQ against a 4-day weighed food record (WFR).

Methods: Reproducibility of the Food4Me FFQ was assessed using test-retest methodology by asking participants to complete the FFQ on 2 occasions 4 weeks apart. To assess the validity of the Food4Me FFQ against the 4-day WFR, half the participants were also asked to complete a 4-day WFR 1 week after the first administration of the Food4Me FFQ. Level of agreement between nutrient and food group intakes estimated by the repeated Food4Me FFQ and the Food4Me FFQ and 4-day WFR were evaluated using Bland-Altman methodology and classification into quartiles of daily intake. Crude unadjusted correlation coefficients were also calculated for nutrient and food group intakes.

Results: In total, 100 people participated in the assessment of reproducibility (mean age 32, SD 12 years), and 49 of these (mean age 27, SD 8 years) also took part in the assessment of validity. Crude unadjusted correlations for repeated Food4Me FFQ ranged from .65 (vitamin D) to .90 (alcohol). The mean cross-classification into “exact agreement plus adjacent” was 92% for both nutrient and food group intakes, and Bland-Altman plots showed good agreement for energy-adjusted macronutrient intakes. Agreement between the Food4Me FFQ and 4-day WFR varied, with crude unadjusted correlations ranging from .23 (vitamin D) to .65 (protein, % total energy) for nutrient intakes and .11 (soups, sauces and miscellaneous foods) to .73 (yogurts) for food group intake. The mean cross-classification into “exact agreement plus adjacent” was 80% and 78% for nutrient and food group intake, respectively. There were no significant differences between energy intakes estimated using the Food4Me FFQ and 4-day WFR, and Bland-Altman plots showed good agreement for both energy and energy-controlled nutrient intakes.

Conclusions: The results demonstrate that the online Food4Me FFQ is reproducible for assessing nutrient and food group intake and has moderate agreement with the 4-day WFR for assessing energy and energy-adjusted nutrient intakes. The Food4Me FFQ is a suitable online tool for assessing dietary intake in healthy adults.

Web Link

Validation Information

Year of Publication

Tool Information

Dietary Exposure Measured
Full Nutrient, Food Groups
Tool Type
Food Frequency Questionnaire
Timeframe Tool Measures info
1 Month
Portion Size Measures info
Reporting Method info
Usual; Retrospective
Format info
Supplements Measured
Administration Method info

Study Information

Study Location
Reading, England
Associated Nutrient Database
WISP Food composition databank (Tinuviel Software, Anglesey, UK) which uses McCance & Widdowson's The Composition of Foods, 5th & 6th editions and supplements.
Comparator Validated Against
Weighed Food Diary


Sample Size
Age of Population

Mean(SD): 26.9(8.4) years

Other Notable Characteristics

Total number of nutrients validated: 20 info

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:

  • Energy
  • Fat
  • Saturated Fat
  • Mono-unsaturated Fat
  • Poly-unsaturated Fat
  • Carbohydrates
  • Protein
  • Sugar
  • Non‐starch polysaccharides(NSP)
  • Sodium
  • Calcium
  • Iron
  • Zinc
  • Retinol
  • Folate
  • Folic Acid
  • Vitamin B12
  • Vitamin C
  • Fruit & Vegetables
  • Urinary Nitrogen

To find information on the other validated nutrients please read the validation study.

  • Energy
  • Macronutrients: 7
  • Micronutrients: 12
Comparator Lifestage Sex Nutrient Measured info Mean Difference Standard Deviation info Correlation Coefficient info Cohen's Kappa Coefficient Percentage Agreement Percentage Agreement Categories info Lower Limits of Agreement Upper Limits of Agreement
Weighed Food Diary Adults Both Energy (kcal) 178 690 0.53 (S) 41 4 -1202 1558
Protein (g) 10 29 0.59 (S) 45 4 -48 68
Fat (g) 11 30 0.56 (S) 37 4 -49 71
Saturated Fat (g) 21 14 0.48 (S) 37 4 -7 49
MUFA (g) 8 6 0.56 (S) 53 4 -4 20
PUFA (g) 2 5 0.45 (S) 49 4 -8 12
Carbohydrates (g) 5 86 0.43 (S) 37 4 -167 177
Total Sugars (g) 16 39 0.60 (S) 41 4 -62 94
Sodium (mg) -228 1096 0.37 (S) 49 4 -2420 1964
Calcium (mg) 178 357 0.47 (S) 41 4 -536 892
Iron (mg) 1.1 5.5 0.50 (S) 41 4 -9.9 12.1
Retinol (µg) 189.9 341.4 0.31 (S) 37 4 -492.9 872.7
Folate (µg) 63.8 121.8 0.58 (S) 45 4 -179.8 307.4
Vitamin B12 (µg) 2.2 3.0 0.46 (S) 39 4 -3.8 8.2
Vitamin C (mg) 41.6 72.1 0.54 (S) 37 4 -102.6 185.8

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.

Fallaize R, Forster H, Macready AL, Walsh MC, Mathers JC, Brennan L, et al. Online dietary intake estimation: reproducibility and validity of the Food4Me food frequency questionnaire against a 4-day weighed food record. Journal of medical Internet research. 2014;16(8):e190.