In a group of 528 men, 30-54 years old, answers to various questions about dietary habits given in a questionnaire were compared to corresponding information given in a dietary history interview two years later. High concordance was found between the two methods for questions concerning types of foods most commonly used. For most food items, the mean intake according to the dietary recall corresponds well with intake reported in the questionnaire. For food items used every day in easily recorded units (slices of bread, cups of coffee, glasses of milk), the frequency questionnaire can be used to rank individuals according to consumption. For other food items, the concordance is less satisfactory.
Three methods of estimating group and individual dietary consumption have been developed and assessed in a case-control study of diet and breast cancer. The methods comprised a 24-hour recall, a detailed quantitative diet history directed to the most recent two-month period and the two-month period six months before, and a four-day diet diary. There is a high degree of correlation between the estimates of food consumption for the controls using each of the methods. The highest estimate was obtained from the diet history, with a slightly higher estimate in the period six months before than the current period, while the lowest is found in the 24-hour recall. The latter corresponds with the same method in a Nutrition Canada Survey. It is concluded that all methods ara applicable to case-control studies, but the diet history is preferred when current food intake may be influenced by a disease.
The reproducibility of a self-administered questionnaire about dietary habits was assessed by comparing answers from 201 men and women to identical questions posed in two surveys separated by approximately one year. In spite of possible changes in the diet in the time period between the two surveys, the concordance between the information was high, both concerning type of food item most commonly eaten and the frequency with which the food items were consumed. The highest reproducibility was found for food items consumed habitually (e.g. alcohol) or often (e.g. coffee). The results are in accordance with most other similar studies, and support the use of self-administered questionnaires in nutritional epidemiology.
A dietary survey concerning 1348 persons aged 25-64 was carried out in connection with the first FINMONICA risk factor survey in the three monitoring areas, North Karelia and Kuopio in the east, and Turku-Loimaa in the south-west in 1982. Three-day food records were used in the dietary assessment. The fat content of the diet in men was 38-39% of energy in all areas, whereas in women it was about 36% in the east compared to 38% in the south-west. The ratio of polyunsaturated to saturated fat of the diet was lower in the east than in the south-west in both sexes (0.25 vs. 0.31). This seemed to be the result of higher milk and butter consumption in the east. The regional differences in the quality of dietary fats seemed to be the result of both different occupational structures and different dietary habits within each occupational group, especially among women.
This study was conducted to evaluate a detailed diet history questionnaire. Diet histories obtained from 16 men were compared with food records kept by their partners for a 30-day period. Mean estimates for all 13 nutrients calculated were higher with the diet history than with food records. Positive correlation coefficients were found between estimates from the two methods for all nutrients as well as food groups and six of the 13 nutrients gave a good fit for the corresponding regression equations. The questionnaire was also evaluated by repeating it after six months on 26 case-control pairs of an ongoing diet and cancer study. High correlation coefficients were obtained for most nutrients for the controls. However, cases showed lower correlations probably due to changes in their diet. The study found that the diet history method as an estimate of dietary patterns among groups shows sufficient validity and reliability to make it a useful instrument for epidemiologic studies.
This study investigates the association of dietary quality with dental caries increment of 11-year-old children. A 3-day dietary record including one weekend day was completed by the subjects and their parents. The nutritional quality was evaluated using a quality index based on the eating frequency of foods recommended in food guides and divided into 8 levels. The frequency of consumption of sugary foods, liquid and solid, at and between meals was also calculated. Two oral examinations 20 months apart were made in 1983-85; each time, the quality of oral hygiene was determined by using the simplified oral hygiene was determined by using the simplified oral hygiene index of Greene and Vermillon. the dental caries increment between the two examinations was evaluated using the DMFS index. When the subjects were distributed into 3 groups according to their nutritional quality index, the mean dental caries increment had a tendency to decrease as the nutritional quality increased for the total sample as well as for boys and girls considered separately; however, the analysis of variance did not reveal any differences of statistical significance. No association was established for children in this study between frequency of consumption of sugary foods and caries increment. No association was observed between nutritional quality and oral hygiene nor between the mother's education and the children's frequency of consumption of sugary foods. Thus, in our study, children with the highest dental caries increment are not necessarily the ones having a diet of poor nutritional quality nor the ones consuming sugary foods more frequently.