Validation Information: Medical Research Council-Caerphilly Questionnaire
Thompson 1993
Comparison of a Food Frequency Questionnaire with a 10-Day Weighed Record in Cigarette Smokers
The aim of the study was to compare nutrient intakes estimated by a self-administered food frequency questionnaire and a 10-day weighed record in 122 men and 179 women cigarette smokers aged 40-59 years. Comparison of nutrient intake by means, per cent mean differences and ability to rank individuals correctly between the methods showed good agreement for most nutrients. Spearman rank correlations were statistically significant for all nutrients except vitamin A intake in men; adjusting for energy intake increased the strength of the associations found. Bland-Altman plots showed differences in agreement over the range of intakes for energy in men and ascorbic acid in women. Food frequency questionnaires may be used to assess the dietary habits of smokers, but some caution is required and the method should be assessed in the study sample before being applied to the whole sample.
Total number of nutrients validated: 16
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: 9
- Micronutrients: 6
| 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Weighed Food Diary | Adults | Male Only | Energy (kcal) | -96 | 537 | 0.38 (S) | -1170 | 979 | |||
| Energy (kJ) | -400 | 2250 | 0.38 (S) | -4900 | 4100 | ||||||
| Protein (g) | -0.2 | 22 | 0.35 (S) | -44 | 44 | ||||||
| Fat (g) | -11 | 31 | 0.34 (S) | -73 | 51 | ||||||
| Saturated Fat (g) | -2 | 27 | 0.45 (S) | -56 | 52 | ||||||
| PUFA (g) | -2 | 7 | 0.56 (S) | -15 | 12 | ||||||
| Carbohydrates (g) | -1 | 77 | 0.54 (S) | -156 | 153 | ||||||
| Total Sugars (g) | 7 | 45 | 0.66 (S) | -90 | 104 | ||||||
| Calcium (mg) | 65 | 276.1 | 0.45 (S) | -487.2 | 617.2 | ||||||
| Iron (mg) | -0.8 | 5.6 | 0.48 (S) | -12.1 | 10.5 | ||||||
| Folate (µg) | 37 | 79 | 0.59 (S) | -121 | 195 | ||||||
| Vitamin C (mg) | 4.2 | 32.1 | 0.51 (S) | -60.1 | 68.4 | ||||||
| Weighed Food Diary | Adults | Female Only | Energy (kcal) | 48 | 652 | 0.36 (S) | -1256 | 1352 | |||
| Energy (kJ) | 200 | 2730 | 0.36 (S) | -5260 | 5660 | ||||||
| Protein (g) | 11 | 20 | 0.35 (S) | -29 | 50 | ||||||
| Fat (g) | -5 | 25 | 0.44 (S) | -55 | 46 | ||||||
| Saturated Fat (g) | -1 | 11 | 0.59 (S) | -22 | 21 | ||||||
| PUFA (g) | -0.2 | 6 | 0.44 (S) | -11 | 11 | ||||||
| Carbohydrates (g) | 12 | 60 | 0.52 (S) | -109 | 132 | ||||||
| Total Sugars (g) | 11 | 39 | 0.61 (S) | -67 | 89 | ||||||
| Calcium (mg) | 123 | 266.2 | 0.53 (S) | -409.4 | 655.4 | ||||||
| Iron (mg) | 1.8 | 5.5 | 0.47 (S) | -9.1 | 12.7 | ||||||
| Folate (µg) | 49 | 68 | 0.49 (S) | -88 | 186 | ||||||
| Vitamin C (mg) | 13.5 | 32.1 | 0.52 (S) | -50.7 | 77.7 |
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.
Thompson RL, Margetts BM. Comparison of a food frequency questionnaire with a 10-day weighed record in cigarette smokers. International Journal of Epidemiology. 1993 Oct 1;22(5):824-33.