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.
As part of the Euronut SENECA study, food consumption has been assessed in 1217 men and 1241 women, born between 1913 and 1918 and living in 18 towns in 12 European countries. The method used was a standardized modified dietary history, including a 3-day estimated record and a food frequency list based on local food patterns. Intakes of energy, protein, fat, carbohydrate, fatty acids, cholesterol and alcohol are described in this paper. As expected, a difference between men and women in energy and nutrient intake was observed in all towns. There was a great variation between towns in mean dietary intakes of all dietary components. Mean energy intake of men ranged from 12.7 MJ in Marki (Poland) to 8.2 MJ in Yverdon (Switzerland) and Chateau Renault-Amboise (France). For women the range was from 10.9 MJ in Marki (Poland) to 6.3 MJ in Yverdon (Switzerland) and Vila Franca de Xira (Portugal). A geographical pattern can be detected for the intake of fatty acids. Intakes of saturated fat were lower in southern than in northern European towns. The calculated ratio for intakes of unsaturated and saturated fatty acids (polyunsaturated fatty acids plus monounsaturated fatty acids/saturated fatty acids) for all participants was higher in the southern European centres than in the northern centres and ranged from 2.7 in Markopoulo (Greece) to 1.2 in Elverum (Norway) and Marki (Poland). Alcohol consumption was considerable higher in men than in women. In men a north-south gradient in alcohol intake can be detected, with the highest intake in the two centres in Italy, where, on average 11% of energy intake was derived from alcohol.
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.
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 authors conducted a dietary methodology study in 1984 in Finnish men aged 55-69 years in order to validate two dietary assessment instruments being used in the US-Finland Alpha-Tocopherol, Beta-Carotene Lung Cancer Prevention Trial. Twelve 2-day food records collected from 162 men over a 6-month period, including every day of the week, served as the reference measure. This report focuses on three important questions for investigating diet and disease relations: 1) How many days are necessary to classify "usual" intake? 2) Is there loss as a result of using consecutive days? 3) Which days are necessary for assessment and classification of "usual" diet? A repeated-measures regression model was used to estimate the variance components and the effects of consecutive days, weekday (weekday vs. weekend), and season. Correlations between the averages of different numbers of days of food records and "true" usual intake were examined along with the resulting attenuations in relative risk. Results suggest that 7-14 days are required to adequately classify most individuals into categories of intake for most nutrients and some foods. There appears to be some loss of information from using consecutive days rather than days further apart. Weekday/weekend differences in mean intakes are slight, and the rank ordering of individuals appears to be preserved. A moderate seasonal effect is shown for classification of fruits, but only a slight one is seen for micronutrients and berries. Implications for the design of epidemiologic and validation studies are discussed.
The objective of the study was to measure the prevalence of overweight and obesity in Mexican school-age children (5-11 years) in the National Nutrition Survey 1999 (NNS-1999).
Overweight and obesity (defined as an excess of adipose tissue in the body) were evaluated through the Body Mass Index (BMI) in 10,901 children, using the standard proposed by the International Obesity Task Force. Sociodemographic variables were obtained using a questionnaire administered to the children's mothers.
The national prevalence of overweight and obesity was reported to be 19.5%. The highest prevalence figures were found in Mexico City (26.6%) and the North region (25.6%). When adjusting by region, rural or urban area, sex, maternal schooling, socioeconomic status, indigenous ethnicity and age, the highest prevalences of overweight and obesity were found among girls. The risks of overweight and obesity were positively associated with maternal schooling, children's age and socioeconomic status.
Overweight and obesity are prevalent health problems in Mexican school-age children, particularly among girls, and positively associated with socioeconomic status, age, and maternal schooling. This is a major public health problem requiring preventive interventions to avoid future health consequences. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.
OBJECTIVE: To assess manifest bias in ageing effects, i.e. longitudinal changes due to unintended time effects or to selection. DESIGN: Mixed-longitudinal study in birth cohorts 1913-1918, with baseline measurements taken in 1988/1989 and repeated in 1993, including a short questionnaire in non-responders. SETTING: Full baseline and follow-up data were collected in nine towns in eight European countries including Belgium, Denmark, France, Italy, The Netherlands, Portugal, Spain and Switzerland. Incomplete data were available from towns in Portugal, Poland, Northern Ireland and Connecticut, USA. SUBJECTS: Using standardized methodologies data were collected from a random age-stratified sample of elderly men and women, including a total of 1221 re-invited subjects from nine towns and 210 newly-invited subjects from three towns in 1993. RESULTS: An overall retrieval of 50-74% of the former participants could be reached in towns that had previously participated (apart from one exception of 41%), where estimates of mortality varied from 10% to 18%. There was a tendency for healthy and active persons to have a higher participation rate than others, as was the case for high educated newly-invited subjects compared to lower educational classes. For most of the variables used in the analysis of period effects, no evidence of any undesirable period effect was found. In those instances that period effects showed up to be statistically significant, coinciding implausible cohort effects gave the impression that these were due to instability of the estimation procedure. CONCLUSIONS: Non-participants may be less healthy and active than the participants. Only very limited unconvincing evidence to suggest unintended time effects was observed. This confirms the high standards of the methodology and of measurements.