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Validation Information: Food Amount Frequency Questionnaire

Hartwell 2001

Comparison of a self-administered quantitative food amount frequency questionnaire with 4-day estimated food records

Our objective was to assess the relative validity of a self-administered food amount frequency questionnaire (FAQ), using 4-day estimated food records (FRs) as a reference method, for use in a subsequent clinical study of patients undergoing heart surgery. Thirty healthy subjects (19 males, 11 females), aged 45-75 years, were randomly recruited from patient lists generated by two local GP practices in Oxford. Complete data from the FAQ and FR, administered twice 6 months apart, were available for 25 subjects (16 males, 9 females). For absolute nutrient values, intakes of protein, CHO, total fat, PUFA, thiamin, iron, dietary fibre and alcohol were not significantly different between the FAQ and FR, and Pearson's correlation coefficients ranged from 0.28 for protein to 0.88 for total fat. Estimates from the FAQ were within ± 10% of the estimates produced by the FR for two-thirds of nutrients. When nutrients were expressed as a percentage of total energy intake, no statistically significant differences were observed for any nutrient between the two methods, and correlations ranged from 0.32 for protein to 0.80 for SFA. In conclusion, the broad dietary patterns obtained by the two methods of assessment were comparable. This simple and inexpensive FAQ can be used to usefully estimate group intakes for a variety of nutrients in the study of patients undergoing heart surgery.

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Validation Information

Year of Publication

Tool Information

Dietary Exposure Measured
Full Nutrient
Tool Type
Food Frequency Questionnaire
Timeframe Tool Measures info
Portion Size Measures info
Subjects were asked to record usual portion size, which were estimates using either common household measures or whole units (i.e. grams, mililitres). Where this was not possible, subjects were asked to indicate whether their usual portion size was 'small, medium or large'. Food photographs of 65 food items were also included.
Reporting Method info
Usual; Retrospective
Format info
Supplements Measured
Not Reported
Administration Method info

Study Information

Study Location
Oxford, England
Associated Nutrient Database
Comparator Validated Against
Food Diary Estimated


Sample Size
Age of Population

Range: 45-75 years

Mean(SE): 58.1(1.7) years

Other Notable Characteristics
Healthy Population. Data for male only and female only is available in the publication.

Total number of nutrients validated: 13 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: 8
  • Micronutrients: 4
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
Estimated Food Diary Adults Both Energy (kcal) 265 464 0.46 (P) -663 1193
Energy (kJ) 1106 1939 0.46 (P) -2772 4984
Protein (g) 8 22 0.28 (P) -36 52
Fat (g) 5 13 0.88 (P) -21 31
Saturated Fat (g) 5 8 0.78 (P) -11 21
MUFA (g) 3 5 0.70 (P) -7 13
PUFA (g) 1 4 0.81 (P) -7 9
Carbohydrates (g) 22 55 0.52 (P) -88 132
Calcium (mg) 145 212 0.63 (P) -279 569
Iron (mg) 1 3 0.64 (P) -5 7
Vitamin C (mg) 21 26 0.79 (P) -31 73

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.

Hartwell DH. Comparison of a self-administered quantitative food amount frequency questionnaire with 4-day estimated food records. International journal of food sciences and nutrition. 2001 Jan 1;52(2):151-9.