Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Portion Size”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources
PubMed2004

Development of a comprehensive dietary antioxidant index and application to lung cancer risk in a cohort of male smokers.

In many observational studies, a higher intake of individual antioxidants is inversely associated with lung cancer risk. Data from in vitro and animal experiments suggest that there are biochemical interactions among antioxidant nutrients; therefore, consideration of multiple antioxidants simultaneously may be important in terms of risk estimation. The authors constructed a dietary antioxidant index and evaluated its ability to predict lung cancer risk within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study cohort. At baseline (1985-1988), 27,111 Finnish male smokers aged 50-69 years completed a dietary questionnaire that assessed usual frequency of consumption and portion sizes for the previous 12 months. A total of 1,787 incident cases of lung cancer were identified during a follow-up period of up to 14.4 years (1985-1999). Principal components analyses were individually applied to the carotenoid, flavonoid, and vitamin E nutrient groups, and summation of retained principal component scores, plus selenium and vitamin C, yielded the composite antioxidant index. In multivariate proportional hazards models, the relative risks for lung cancer according to increasing quintiles of the antioxidant index were 1.00 (referent), 1.00 (95% confidence interval (CI): 0.87, 1.14), 0.91 (95% CI: 0.79, 1.05), 0.79 (95% CI: 0.68, 0.92), and 0.84 (95% CI: 0.72, 0.98) (p for trend = 0.002). These findings support the hypothesis that a combination of dietary antioxidants reduces lung cancer risk in male smokers.

Aged↗
PubMed1991

Dietary and non-dietary predictors of serum total and HDL-cholesterol in men and women: results from the Scottish Heart Health Study.

UNLABELLED: An analysis of the associations between dietary and non-dietary variables and serum total cholesterol (Total-C) and high density lipoprotein cholesterol (HDL-C) was performed using data from the Scottish Heart Health Study--a cross-sectional survey of men (n = 5123) and women (n = 5236), aged 40-59. Subjects completed a questionnaire which provided health, socio-demographic and food frequency data. Nutrient intakes were calculated from UK food composition tables using standard portion sizes. For men, the significant independent dietary predictors of Total-C, after adjustment for all the other dietary variables, were saturated fat and cereal fibre, and after adjustment for the non-dietary variables, were cereal fibre, saturated fat and cholesterol. For women, intake of vegetable fibre, white fish and beta-carotene were significant independent predictors of Total-C after adjustment for all the other dietary variables. Only beta-carotene remained significant after adjustment for all the non-dietary variables. Alcohol intake and body mass index were respectively the strongest positive and negative predictors of HDL-C for both sexes. IN CONCLUSION: (1) certain dietary factors may affect serum cholesterol levels differently for men and women; (2) a possible role for the antioxidant vitamins and fibre in the prediction of serum cholesterol, may be indicated, in addition to the 'classical' role of dietary cholesterol and saturated fat and (3) confounding between the social and dietary variables does occur, and confirms the need for multiple adjustments in studies of this nature.

Adult↗
PubMed1991

Validation of a semiquantitative food frequency questionnaire developed in Denmark.

In 1989, a self-administered food frequency questionnaire, including 92 food items and 40 portion-size photographs, was validated against two times seven days of weighed diet records. A total of 144 subjects, aged 40-64 years, from the general population in Copenhagen were included. Correlations between mean calorie-adjusted intakes from the two-week diet records and the food-frequency questionnaire ranged from 0.27 for vitamin A to 0.71 for calcium. In general, higher correlation coefficients were observed for men than for women. On average, about 70% of subjects were classified in the same (+/- 1) quintile in the food frequency questionnaire and the diet records. Of those subjects belonging to the lowest quintile, estimated from the diet records, 42% fell in the same quintile and 68% into the lowest two quintiles in the food frequency questionnaire. Findings were similar for the upper tail of the distribution. Gross misclassification, observed in the highest and lowest quintile, was found for 4% and 7% of the subjects, respectively. It is concluded that this food frequency questionnaire is a useful instrument for categorizing individuals according to their intake of nutrients and energy.

Adult↗
PubMed1993

Salt and gastric cancer: a case-control study in Puerto Rico.

A total of 136 incident intestinal type gastric cancer cases and 151 age-comparable population controls were interviewed in Puerto Rico about their dietary habits with special emphasis on dietary salt consumption. All interviews were conducted at home using a quantitative dietary frequency instrument. The weekly intake of foods was estimated from the reported frequency of consumption and portion size according to a food model. The dietary salt exposure was estimated from the intake of nine selected food items which are highly salted food items commonly consumed in Puerto Rico. A strong (odds ratio [OR] = 3.34) and statistically significant (P < 0.001) unadjusted difference was found between cases and controls regarding dietary salt exposure. A statistically significant dose response for the index of salt exposure and gastric cancer was also found. The association remained positive and statistically significant after simultaneously adjusting for the confounding effects of sex, education and cigarette smoking.

Adenocarcinoma↗
PubMed1997

Relative validity and reproducibility of a French dietary history questionnaire.

BACKGROUND: A self-administered dietary history questionnaire, especially developed for use in a large French prospective cohort study, was tested for accuracy of food intake measurement by comparing it to the average of 9-12 24-hour recalls. This questionnaire was structured according to the French meal pattern. An important feature of the questionnaire was the separation into a quantification part and qualification part. The first part quantifies consumption by frequency and portion sizes per food group or food item. The second part provides more detailed qualitative information on separate items within one food group. The total number of food items in the questionnaire was 238. METHODS: The questionnaire was administered twice to 119 study subjects, with an interval of approximately one year (1990-1991). During that year, 24-hour recalls were carried out monthly. Reproducibility and relative validity of the questionnaire were assessed. RESULTS: The correlation coefficients for reproducibility ranged from 0.40 to 0.74 for foods and from 0.54 to 0.75 for nutrients. The correlation coefficients for relative validity ranged from 0.10 to 0.71 for foods and from 0.29 to 0.81 for nutrients (adjustment for total energy and attenuation for nutrients). Percentage of subjects classified in the same or adjacent quintile by questionnaire as well as by 24-hour recall was on average 76% for foods and 72% for nutrients. CONCLUSIONS: These data indicate that this questionnaire can be used to classify study subjects according to their food or nutrient intake over a one-year period, within a known degree of precision.

Adult↗
PubMed1997

Relative validity and reproducibility of a food frequency dietary questionnaire for use in the Italian EPIC centres.

A pilot questionnaire was developed for the EPIC centres of northern Italy, and validated in the feasibility part of the cohort project. The questionnaire was self-administered and of the food frequency type with portion size estimated by means of pictures. It was structured by courses within a meal characteristic of Italian dietary habits. Dietary intake estimated by the questionnaire was compared to the corresponding estimates obtained from 8-14 24-hour recall interviews administered over a 1-year period. The reference method was validated by means of urinary nitrogen in 4-6 repeated 24-hour urine collections. One hundred and ninety-seven volunteers (47 men and 150 women) were enrolled and completed the study lasting 1 year. They filled out two questionnaires at the beginning and at the end of the study, and had a 24-hour recall interview once a month. Twenty-four-hour urine samples were collected at regular intervals. Usual intake of energy, the major nutrients and some vitamins were estimated for the questionnaires and the reference method by means of food composition tables compiled for this study. The agreement between the questionnaire and the 24-hour recalls was only good for alcohol consumption: Pearson's correlation was 0.73 and 0.77 in men and women respectively. Otherwise the relative validity of the questionnaire ranged between 0.28 for fat to 0.52 for carbohydrates in men and 0.25 and 0.50 in women for the same nutrients. The validity of the two interview methods in estimating protein intake, compared to mean urinary nitrogen was 0.24 (M) and 0.18 (W) for the questionnaire and 0.63 (M) and 0.48 (W) for 24-hour recalls. The main causes of low performance of the questionnaire were identified to be the estimated intake of dressing and cooking fats, vegetables and meat. Remedies were devised and introduced in the final version of the questionnaire currently in use in the EPIC project.

Cohort Studies↗
PubMed1997

The Malmö Food Study: validity of two dietary assessment methods for measuring nutrient intake.

BACKGROUND: Nutritional epidemiology relies largely on dietary assessment methods for the estimation of the "exposure' variables which may be related to disease risk. METHODS: This paper describes a methodological study conducted in Malmö, Sweden, to compare nutrient intake--estimated by two alternative dietary assessment methods--with a reference method consisting of 18 days of weighed food records. The two candidate methods were an extensive food frequency questionnaire with portion size to be estimated from a booklet of 120 sets of photos (method A) and a method involving the combination of a shorter questionnaire and a two-week food record (method B). RESULTS: In absolute values, both methods overestimated nutrient intake by 20-40%, with method B closer to the reference for most nutrients. Both crude and energy-adjusted correlations between A-reference and B-reference were of the order of 0.50-0.60 for energy, energy-providing nutrients and most vitamins and minerals. Correlations were in the same range for most of the 14 fatty acids considered in the analyses. Protein intake, estimated from the analyses of urinary nitrogen on 6-8 repeated 24-hour urine collections per subject, was almost identical to the reference method values. Correlation between nitrogen-derived values and dietary measurement was 0.75. CONCLUSIONS: Overall, the study indicated that both methods A and B had good ranking validity compared to the reference and that in most cases the combined method (B) performed slightly better than the extensive food frequency method (A).

Aged↗
PubMed1997

Reproducibility and relative validity of food group intake in a food frequency questionnaire developed for the German part of the EPIC project. European Prospective Investigation into Cancer and Nutrition.

BACKGROUND: For the German part of the European Prospective Investigation into Cancer and Nutrition (EPIC), a self-administered, optically-readable food frequency questionnaire (FFQ), including 158 food items and 87 coloured portion size photographs, was developed to assess the usual food and nutrient intake of individuals during the past year. In 1991/1992, the reproducibility and validity of the questionnaire measurements were studied according to the EPIC protocol. This article reports the results on reproducibility and relative validity of measurement of food group intake. METHODS: A total of 104 men and women aged 35-64 years, who are members of the local health insurance institution, AOK Heidelberg, participated in this study. Reproducibility of the questionnaire measurements was obtained by a repeated administration of the FFQ to the same study subjects at a 6-month interval. The mean of 12 24-hour dietary recalls applied at monthly intervals served as reference method for the estimation of the relative validity of questionnaire measurements. A second version of the FFQ that integrated questions on general food consumption patterns was also investigated. RESULTS: Spearman test-retest correlations of food group intake ranged from 0.49 for bread to 0.89 for alcoholic beverages (median = 0.70). Spearman correlations between food group intake values derived from the 24-hour diet recalls and the FFQ completed in the summer of 1992 varied from 0.14 for legumes to 0.90 for alcoholic beverages (median = 0.45). Correction for attenuation due to within-person error in the reference method as well as the correction for general consumption patterns improved the correlations. CONCLUSION: The results indicate that our newly developed FFQ gives reproducible estimates of food group intake. Large day-to-day variation in food group intake complicated the evaluation of FFQ validity. Overall, moderate levels of relative validity were observed for estimates of food group intake.

Adult↗
PubMed1997

Reproducibility and relative validity of energy and macronutrient intake of a food frequency questionnaire developed for the German part of the EPIC project. European Prospective Investigation into Cancer and Nutrition.

BACKGROUND: For use in the German part of the European Prospective Investigation into Cancer and Nutrition (EPIC) a self-administered, optically readable food frequency questionnaire (FFQ) was developed to assess individuals' usual food and nutrient intake over the past year. The food list comprised 158 food items for which the typical portion size, the consumption frequency (1-6 times) and the time period (day, week, month, or year) were requested. This paper reports the results of the reproducibility and relative validity of nutrient intakes obtained by this instrument. METHODS: The study was carried out from October 1991 to October 1992. During this period, 104 men and women, aged 35-64 years, completed a 24-hour recall once a month, and the FFQ in the middle and at the end of this study. A short questionnaire on global consumption patterns was used to adjust the food consumption frequency given in the FFQ. RESULTS: Reproducibility correlations varied from 0.59 for saturated fat to 0.88 for alcohol, with most values falling between 0.60 and 0.70. Energy-adjustment decreased the observed correlations for all nutrients. Correlations between nutrient intake values from the 12-day average of dietary recalls and the FFQ corrected for food consumption frequency ranged from 0.42 for polyunsaturated fat to 0.88 for alcohol, followed by 0.65 for dietary fibres. After de-attenuation and energy-adjustment the range of correlations was somewhat wider (0.43-0.75, without alcohol). With regard to classification, on average, 36% of subjects fell into the same quintile, and 75% into within-one quintile when classified by the frequency-corrected FFQ compared to the quintiles based on recalled data. CONCLUSIONS: In summary, the newly developed FFQ showed fairly good reproducibility and relative validity for most evaluated nutrients. The between-subject variation of nutrients in the German cohort (including the participants from East Germany) is likely to be greater than that among the subjects of the pilot phase. A revised version of the FFQ corrected for food consumption frequency is used in the EPIC study.

Adult↗
PubMed1997

Relative validity and reproducibility of a diet history questionnaire in Spain. I. Foods. EPIC Group of Spain. European Prospective Investigation into Cancer and Nutrition.

BACKGROUND: A pilot study was carried out to evaluate the relative validity and reproducibility of a dietary history questionnaire (DH) designed to be used in Spain as part of a prospective European research project on diet and cancer. METHODS: A total of 91 volunteers (46 men and 45 women) aged 35-60 years, and of various occupational categories, participated in the study. The DH was structured according to occasions of intake and was administered twice by interview, with a year's interval. Twelve 24-hour diet recalls, administered monthly between the two administrations of the DH, were used as a reference method. Natural units, geometric figures and a set of photographs were used to quantity portion size. RESULTS: Of a total of 17 food groups, the Pearson correlation coefficients between the daily intake of food groups, based on the mean of 12 24-hour diet recalls, and the second DH showed values between 0.65 and 0.90 in 14 groups (potatoes, vegetables, fruits, cheese, other dairy products, bread, other cereals, meat and poultry, fish and shellfish, butter, margarine and oils, sugar and sweets, other desserts, alcohol and coffee and tea) in males and in 11 groups (potatoes, other vegetables, fruits, cheese, other dairy products, bread, meat and poultry, fish and shellfish, sugar and sweets, alcohol and coffee and tea) in females. In comparison with the mean of 12 24-hour diet recalls the DH questionnaire over-estimated (in both sexes) the intake of vegetables, cereals, butter, margarine and oils and underestimated the intake of sugar and sweets, and other desserts. CONCLUSIONS: The DH method is more expensive and more difficult to apply than other instruments but it provides good information on the habitual food intake of the individual.

Adult↗
PubMed1998

Development of data-based semi-quantitative food frequency questionnaire for dietary studies in middle-aged Japanese.

BACKGROUND: We designed a data-based semi-quantitative food frequency questionnaire to clarify the relationship between food intake and lifestyle-related diseases among middle-aged Japanese. METHODS: A total of 351 middle-aged individuals were recruited to a one-day weighed diet record survey in 1994. In all, 586 foods were consumed. Intake of 31 nutrients including energy, protein, fat, carbohydrate, vitamins, minerals and dietary fiber by food was computed by multiplying the weight of food consumed by its nutrient content. First, 252 foods with up to 90 cumulative % contribution to nutrient intake were selected. Of these, foods having apparently the same/similar nutrient content were combined into 206 foods by research dietitians. Next, 183 foods with up to 0.90 cumulative multiple regression coefficient and 90 cumulative % contribution were chosen. At this stage an additional food grouping was made. RESULTS: Finally, 102 foods/recipes were included in the questionnaire: rice (2 items), bread and noodles (11), eggs, milk and dairy products (10), soybean, soybean products and other beans (7), meat including beef, pork and chicken (12), fish (5), other fish, shellfish and fish products (10), green-yellow vegetables (8), other vegetables and mushrooms (7), edible roots (2), seaweeds (3), seeds (2), fruits (8), beverages (7) and confectioneries (8). The frequencies were classified into eight categories. Portion size was calculated for the respective foods largely from the one-day weighed diet record. CONCLUSIONS: The developed semi-quantitative food frequency questionnaire substantially covered the intake of 31 nutrients and may be competent to rank middle-aged Japanese efficiently.

Databases as Topic↗
PubMed1998

Eating from a shared plate affects food consumption in vitamin A-deficient Nepali children.

This case-control study evaluates the relationship between shared-plate eating behavior in young Nepali children (aged 1-6 y) and risk of vitamin A deficiency. Day-long observations of dietary practices were conducted on 7 d over a 15-mo period in 162 households: 81 households with a child with a known history of mild xerophthalmia (cases) were matched with 81 having a non-xerophthalmic child of similar age (controls). Shared-plate eating occurred in 25% of all feeding episodes and at least once in 65% of all days observed. Overall, children engaging in shared-plate eating were significantly more likely to consume grains, vegetables, carotenoid-rich vegetables, pulses, fruits, meats and fish, and dairy products and had significantly larger portion sizes for grains, vegetables, fruits, pulses and dairy products, compared with children who ate alone. In general, feeding behaviors between case and control children tended to be similar. However, shared-plate feeding episodes among case children were significantly less likely to include meats or fish [odds ratio (OR) = 0.5, confidence interval (CI) = 0.3-0.8], dairy products (OR = 0.6, CI = 0.4-0.9) or pulses (OR = 0.7, CI = 0.5-1.0). Individual-plate feeding episodes among case children were more likely to include vegetables (OR = 1.3, CI = 1.0-1.6) than those of control children. Case children were more likely to share a plate with a male adult (OR = 1.7, CI = 1.0-2.8), but less likely to eat from a plate shared with females of any age compared with controls (female adult: OR = 0.6, CI = 0.4-0.9; female child: OR = 0.6, CI = 0.4-1.0). Shared-plate eating may benefit a young child's dietary intake, but the identity of the food sharer may modify this influence.

Adult↗
PubMed1999

Dietary vitamin A intakes of preschool-age children in South India.

The vitamin A intake of children aged 1-3 y (n = 683) was assessed using a quantitative food-frequency questionnaire in a vitamin A intervention study in South India. Trained field workers interviewed mothers about their children's usual consumption of common sources of vitamin A and collected information on portion sizes using standard cups. Mothers were asked to state the number of months in a year during which specific seasonal foods were available. Information about current breast-feeding was also obtained. Vitamin A intakes from nonbreast milk sources were extremely low at all ages. The median intake of total vitamin A, beta-carotene and retinol was 121, 100 and 21 retinol equivalents (RE), respectively. Maternal education and socioeconomic status (SES) were positively associated with total vitamin A and retinol intakes. Girls had significantly lower intakes than boys even after adjusting for differences in age, maternal education, SES and breast-feeding status. Breast-feeding was common, but declined to 60% by 24 mo and to 15% by 36 mo. Vitamin A intakes from nonbreast milk sources increased with age only for currently breast-fed children, who tended to be of lower SES. After taking into account the potential contribution of breast milk by using published estimates, nonbreast-fed children met only 60% of the Indian recommended dietary allowance (RDA; 250 RE/d), whereas breast-fed children met approximately 90% of the RDA during y 2 of life.

Anthropometry↗
PubMed2002

A cost constraint alone has adverse effects on food selection and nutrient density: an analysis of human diets by linear programming.

Economic constraints may contribute to the unhealthy food choices observed among low socioeconomic groups in industrialized countries. The objective of the present study was to predict the food choices a rational individual would make to reduce his or her food budget, while retaining a diet as close as possible to the average population diet. Isoenergetic diets were modeled by linear programming. To ensure these diets were consistent with habitual food consumption patterns, departure from the average French diet was minimized and constraints that limited portion size and the amount of energy from food groups were introduced into the models. A cost constraint was introduced and progressively strengthened to assess the effect of cost on the selection of foods by the program. Strengthening the cost constraint reduced the proportion of energy contributed by fruits and vegetables, meat and dairy products and increased the proportion from cereals, sweets and added fats, a pattern similar to that observed among low socioeconomic groups. This decreased the nutritional quality of modeled diets, notably the lowest cost linear programming diets had lower vitamin C and beta-carotene densities than the mean French adult diet (i.e., <25% and 10% of the mean density, respectively). These results indicate that a simple cost constraint can decrease the nutrient densities of diets and influence food selection in ways that reproduce the food intake patterns observed among low socioeconomic groups. They suggest that economic measures will be needed to effectively improve the nutritional quality of diets consumed by these populations.

Costs and Cost Analysis↗
PubMed2002

Biobehavioral influences on energy intake and adult weight gain.

U.S. adults are now gaining more weight and becoming obese at an earlier age than in previous years. The specific causes of adult weight gain are unknown, but may be attributed to a combination of factors leading to positive energy balance. U.S. food supply data indicate that Americans have had a gradual increase in energy intake since 1970, and that per capita energy intake was 1.42 MJ/d (340 kcal/d) higher in 1994 than that in 1984. In contrast, self-reported physical activity remained constant between 1990 and 1998. Taken together, these data indicate that the increasing trend in U.S. adult weight gain is primarily attributable to overconsumption of energy. Epidemiological and experimental studies in animals and humans provide strong evidence that biobehavioral factors such as dietary variety, liquid (vs. solid) energy, portion size, palatability (taste), snacking patterns, restaurant and other away-from-home food, and dietary restraint and disinhibition influence hunger, satiety and/or voluntary energy intake. When these eating behaviors are consistently experienced either separately or in combination over the long term, they are likely to facilitate overeating. We provide a brief overview of the evidence to date for the role of these biobehavioral factors in contributing to excess energy intake and increases in body weight over time.

Adult↗
PubMed2002

Why do children become vitamin A deficient?

Vitamin A deficiency is very prevalent and contributes substantially to morbidity and mortality among young children in developing countries. We identify and quantify three causes of vitamin A deficiency in young children based on data available in the literature: maternal vitamin A deficiency resulting in low concentrations of vitamin A in breast milk, inadequate dietary intake of vitamin A during and after weaning and prevalent illness. We developed a set of recursive equations to estimate the amount of vitamin A in the liver as a function of age over the first 2 y of life. To apply the equations, we selected a best estimate value for each input parameter as the most representative of a typical child in a developing country. Because of the great variability that exists for each variable, we also carried out sensitivity analyses, substituting more extreme values for input parameters. We then estimated stores, assuming a child in a developing country also receives the newly revised vitamin A supplementation regimen recommended by the World Health Organization. Without supplementation, a typical child in a developing country is not able to attain and maintain "minimally adequate" liver vitamin A stores. To overcome this deficit by eating fruits and vegetables alone, the child would need to increase portion sizes about 10-fold. If the child receives the new supplementation regimen, his or her liver stores will still be far short of the average American child (i.e., exceedingly far from toxic levels). However, our estimates indicate that the new supplementation regimen will permit a typical child in a developing country setting to attain minimally adequate vitamin A stores during the first 2 y of life.

Bangladesh↗
PubMed1998

Diet during adolescence and risk of breast cancer among young women.

BACKGROUND: A variety of breast cancer risk factors pertain to a woman's adolescence and may be related to nutritional influences. We assessed risk of early-onset breast cancer related to diet during adolescence in a case-control study. METHODS: Study participants were accrued from the following three geographical regions covered by cancer registries: Atlanta, GA; Seattle/Puget Sound, WA; and central New Jersey. Case patients (n = 1647) were newly diagnosed with breast cancer, and control subjects (n = 1501) were identified by random-digit-dialing techniques. In an interview, each subject was asked to recall the frequency of consumption and portion size of 29 key food items at ages 12-13 years. Mothers of a subset of respondents completed questionnaires, and food groups were recalculated after removal of foods with poor agreement between mother and daughter. Logistic regression analyses were used to calculate odds ratios and 95% confidence intervals. RESULTS: When high versus low quartiles of consumption were compared, there was a suggestion of a reduced risk associated with high consumption of fruits and vegetables, although this finding was not statistically significant. Slight increases (of borderline statistical significance) in risk of breast cancer were found for intake of chicken or high-fat meat. Intake of animal fat, high-fat foods, high-fat snacks and desserts, or dairy products during adolescence had no apparent influence on breast cancer risk. Removal of foods suspected to be poorly recalled by the daughters did not change any of the risk estimates. CONCLUSION: These data do not provide evidence for a strong influence of dietary intakes during adolescence on risk of early-onset breast cancer.

Adolescent↗
PubMed1998

Validity of dietary recall over 20 years among California Seventh-day Adventists.

Past dietary habits are etiologically important to incident disease. Yet the validity of such measurements from the previous 10-20 years is poorly understood. In this study, the authors correlated food frequency results that were obtained in 1994-1995 but pertained to recalled diet in 1974 with the weighted mean of five random 24-hour dietary recalls obtained by telephone in 1974. The subjects studied were 72 Seventh-day Adventists who lived within 30 miles of Loma Linda, California; had participated in a 1974 validation study; were still alive; and were willing to participate again in 1994. A method was developed to allow correction for random error in the reference data when these data had differentially weighted components. The results showed partially corrected correlation coefficients of greater than 0.30 for coffee, whole milk, eggs, chips, beef, fish, chicken, fruit, and legumes. Higher correlations on average were obtained when the food frequencies were scored simply 1-9, reflecting the nine frequency categories. The 95% confidence intervals for 15 of the 28 correlations excluded zero. Incorporation of portion size information was unhelpful. The authors concluded that in this population, data recalled from 20 years ago should be treated with caution but, for a number of important foods, that the degree of validity achieved approached that obtained when assessing current dietary habits.

California↗