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OBJECTIVE: Diet validation research was conducted to compare the respondents' reporting of dietary intake in a food frequency questionnaire (FFQ) with intake reported in food recalls. Because the population received annual salary increments that could modify food intake, diet validation studies (DVSs) were conducted during two time intervals. DESIGN: A 99-item FFQ was administered by an interviewer twice in a 1-year interval, and responses to each FFQ item were compared with 28 days of interviewer-administered food recalls that were collected in four 1-week intervals during each season of 1992/93. The second validation study in 1995/96 had a similar design to the earlier one. SETTING: A prospective cohort study of lung cancer among tin miners in China was initiated in 1992, with dietary and other risk factors updated annually. SUBJECTS: Among a cohort of high risk tin miners for lung cancer, two different samples (n = 141 in 1992/93, and n = 113 in 1995/96) for each diet validation study were randomly selected from four mine units, that were representative of all worker units. RESULTS: Miners reported a significantly higher average frequency of intake of foods in the food recalls than the FFQ, with few exceptions. Deattenuated Pearson correlation coefficients of the frequency of food intake between the FFQ and food recalls were in the range of -0.40 to 0.72 in both studies, with higher positive correlations for beverages and cereal staples than for animal protein sources, vegetables, fruits and legumes. The percentage of individuals with exact agreement in the extreme quartiles of intake in the food recalls and FFQ ranged from 0 to 100% in both studies. CONCLUSIONS: Among Chinese miners, the range in correlations between the food recalls and the FFQ were due to: (i) market availability of foods during the food recall weeks compared to their annual reported intake in the FFQ; (ii) cultural perception of time; and (iii) differences in how the intake of mixed dishes and their multi-ingredient foods were reported in the recalls vs. the FFQ. The range in the percentage of agreement in the same quartiles and the changes in food intake over time may have implications for the analysis of the diet-disease relationship in this cohort.

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The relation between the dietary intake of vitamins E, C, and A (estimated by a 24-hour recall) and lung cancer incidence was examined in the First National Health and Nutrition Examination Survey Epidemiologic Followup Study cohort of 3,968 men and 6,100 women, aged 25-74 years. During a median follow-up period of 19 years (from 1971-1975 to 1992), 248 persons developed lung cancer. Adjusted for potential confounders using Cox proportional hazards regression methods with age as the underlying time variable, the relative risk of lung cancer for subjects in the highest quartile of vitamin C intake compared with those in the lowest quartile was 0.66 (95% confidence interval (CI) 0.45-0.96). For vitamin A intake, a protective effect was observed only for its fruit and vegetable component (carotenoids) among current smokers (relative risk = 0.49, 95% CI 0.29-0.84), but this was modified by the intensity of smoking (a statistically significant effect (relative risk = 0.33, 95% CI 0.13-0.84) was observed only for those in the lowest tertile of pack-years of smoking). The vitamin E intake-lung cancer relation was modified by the intensity of smoking with a significant protective effect confined to current smokers in the lowest tertile of pack-years of smoking (relative risk = 0.36, 95% CI 0.16-0.83). Overall, there was no additional protective effect of supplements of vitamins E, C, and A beyond that provided through dietary intake. When vitamin E, vitamin C, and carotenoid intakes were examined in combination, a strong protective effect was observed for those in the highest compared with those in the lowest quartile of all three intakes (relative risk = 0.32, 95% CI 0.14-0.74). These data provide support for a protective role of dietary vitamins E and C and of carotenoids against lung cancer risk but with a modification in effects by the intensity of cigarette exposure. While smoking avoidance is the most important behavior to reduce lung cancer risk, the daily consumption of a variety of fruits and vegetables that provides a combination of these nutrients and other potential protective factors may offer the best dietary protection against lung cancer.

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Supplement intake is hypothesized to increase the risk of some diseases while decreasing the risk of others. Both diet and lifestyle behaviors, however, may be associated with supplement use and confound observed associations. Nutrient intake from a food frequency questionnaire, demographic characteristics and lifestyle among supplement users and nonusers were examined in 11,643 adults who participated in the 1992 National Health Interview Survey Epidemiology Supplement. Forty-six percent reported taking a supplement in the past year; 24% reported daily use. Daily use was highest among women, whites, those 75 y of age or older, those at or above the poverty level, those with more than 12 y of education, former smokers, and light drinkers consuming less than one alcoholic beverage per week. When controlled for sociodemographic factors, smoking status and drinking habits, there were no significant (P < 0.01) differences in dietary nutrient intake between daily and occasional supplement users. Compared with those of nonusers, diets of vitamin supplement users were lower (P < 0.001) in fat and higher in fiber and vitamins A and C for both men and women and higher in vitamin E and calcium for women only. In general, diet, demographic and lifestyle characteristics of supplement users are typical of patterns associated with low risk of chronic disease.

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OBJECTIVE: To examine the hypothesis that an energy-dense, high-fat diet, which is necessary to maintain weight in adults with cystic fibrosis, does not result in high serum cholesterol levels. DESIGN: Dietary, anthropometric, and biochemical data were correlated. SETTING: A cystic fibrosis center in Pittsburgh, Pa. SUBJECTS: Thirty-one adults with cystic fibrosis, 50 obligate carriers of the cystic fibrosis gene, and 26 controls who did not have cystic fibrosis. MAIN OUTCOME MEASURES: Adults with cystic fibrosis had a lower mean serum cholesterol level and higher mean intakes of energy and fat than controls. STATISTICAL ANALYSES PERFORMED: Student's t test was used to determine the statistical significance between two means. Univariate correlation coefficients were determined to measure the relative intensity of association between two variables. RESULTS: Mean total serum cholesterol levels in men with cystic fibrosis was 3.1 mmol/L vs 4.7 mmol/L in male controls (P < .001). Mean total serum cholesterol levels in women with cystic fibrosis was 3.2 mmol/L vs 4.3 mmol/L in female controls (P < .001). Three adults with cystic fibrosis and no signs of pancreatic insufficiency had serum cholesterol levels in the high normal range. Carriers had serum lipid levels in the same range as the controls. CONCLUSIONS/APPLICATIONS: The findings indicate that a high-energy, high-fat diet does not raise serum lipid levels in those patients with cystic fibrosis and pancreatic insufficiency. However, those individuals with cystic fibrosis and normal pancreatic function may be at the same risk as the general population for developing high serum lipid levels. They should have their serum lipid levels monitored and be given appropriate dietary recommendations.

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Hysterectomy is one of the most commonly performed major operations in the United States. Despite efforts to explain its high incidence, the perception remains that a significant number of hysterectomies are unjustified. More indications are listed for hysterectomy than for any other major operation. A quality assurance process is presented that requires the surgeon to select preoperatively one designated indication for each hysterectomy performed. The pathology report is expected to verify the surgical indication in 66% of the cases. The other 34% of hysterectomy specimens are not expected to show tissue pathology based on the listed indication. For these cases, predetermined validation criteria must be satisfied in the surgeon's preoperative note. Applying the process in this series of 584 consecutive hysterectomies, 93% (N = 396) of the "pathology expected" indications were verified by the pathology report and 98% (N = 188) of the "no pathology expected" indications were validated by the surgeon's preoperative note. The process of using a single designated indication and reviewing only two documents (the pathology report and the surgeon's preoperative note) has greatly simplified the quality assurance process. This system enables a quality assurance committee to monitor easily the appropriateness of hysterectomy indications for their institution. Information obtained from this process can influence changes regarding the acceptability of certain indications. As a result of this study, adenomyosis, because of its low (38%) verification rate, is no longer considered a reliable preoperative indication for hysterectomy at San Diego Naval Hospital.

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