Estimating the variations and autocorrelations in dietary intakes on weekdays and weekends.

The high incidence of breast cancer in the U.S. and the possible link with dietary fat has led to the development of educational programmes for reducing women's fat intakes by agencies such as the National Cancer Institute and the U.S. Department of Agriculture. In this paper, we analyse the effects of an intervention on the intakes of 12 nutrients by 37 women in the Houston area. We estimate a dynamic random effects model by maximum likelihood to estimate the between and the within variations and the autocorrelations using 7 consecutive food records before and after the intervention programme. The main findings are that the pattern of within variations differs during weekdays and weekends. Secondly, the mean intakes of nutrients such as beta-carotene and ascorbic acid tend to be lower on weekends. Lastly, the intervention programme reduced the overall fat intakes and also increased the variation in the consumption of foods high in fats during weekdays. We discuss the implications of the results for the design of further studies.

Investigation of nonresponse bias: Hispanic Health and Nutrition Examination Survey.

This report presents an investigation of potential nonresponse bias in the Hispanic Health and Nutrition Examination Survey (HHANES) conducted during the period 1982-84. Data from a household and medical history interview were used to investigate factors related to examination status. The study includes a comparison of data for examinees in HHANES with data from interviewees in the National Health Interview Survey during 1982, 1983, and 1984.

Comparison of tooth surface-specific dental caries attack patterns in US schoolchildren from two national surveys.

The 1979-1980 and the 1986-1987 National Institute of Dental Research (NIDR) surveys of school-aged children revealed that virtually all tooth surfaces experienced a decrease in caries prevalence during the inter-survey period. Overall, there was a 28% decrease in the proportion of tooth surfaces attacked by caries for the primary dentition between the two surveys. The decrease for primary incisors was numerically small (5 surfaces per thousand surfaces at risk) and not statistically significant, whereas decreases in the canines and primary molars were considerably larger (23 surfaces per thousand) and statistically significant. For the permanent dentition, the overall decrease in the proportion of surfaces attacked was 35% during the 1979-87 period. Differences between the two surveys in the proportions of surfaces with caries were largest for pit and fissure surfaces (56 surfaces per thousand), followed by those for posterior approximal surfaces (14 surfaces per thousand) and all other smooth surfaces (5 surfaces per thousand). Almost all of these differences were statistically significant, except for some surfaces which experienced very few caries.

Adjusting for nonresponse bias in a health examination survey.

There is a potential for nonresponse bias in most population studies using health examinations. This is true of the Mexican American portion of the Hispanic Health and Nutrition Examination Survey (HHANES), conducted by the National Center for Health Statistics, in which unit nonresponse to the examination accounted for 24 percent of the sample. Even though the full effect of nonresponse can never be really known, ancillary information from the interview sample can be used in an attempt to adjust for bias in estimates. Two techniques for nonresponse bias adjustment are presented and illustrated using health status level and hypertension status from published studies based on the HHANES of 1982-84. The first approach uses conditional probabilities and the second approach uses direct standardization. The examples examine whether or not an adjustment for socioeconomic status, sex, and age--variables related to both response status and the conditions under study--changes the prevalence estimates of (a) Mexican Americans who report poor, fair, or good health status and (b) hypertension among Mexican Americans.

National standards of blood pressure for children and adolescents in Spain: international comparisons. The Spanish Group for the Study of Cardiovascular Risk Factors in Childhood and Youth.

This study determined age-specific patterns of blood pressure (BP) in Spanish children aged 1-18 years for the purpose of developing BP guidelines for this population. Age- and sex-specific BP levels were constructed by pooling data from 15 studies conducted in Spain. Pooled mean BP levels were then compared with those reported by the US Second Task Force on Blood Pressure Control in Children and those recently reported from a separate pooled analysis of the relevant published surveys collected worldwide. In the Spanish data, the average 1-year age increment in Systolic BP (SBP) was uniform for boys and girls until 13 years at 2 mmHg; for boys aged 13-18 the increase was 1.3 mmHg/year; in contrast, girls reached their maximum values at age 13 and the means remained basically unchanged for female adolescents. Fifth-phase diastolic BP (DBP5) values showed a uniform increase for both boys and girls from ages 6 to 18 years at 0.9 mmHg/year. In most age-sex subgroups, mean SBP values were higher (7-8 mmHg on average) in Spain than in the US. However, Spanish values for SBP were in general only slightly higher or approximately equal to those for the international data, from ages 6 to 18 years. The patterns of change in SBP with age differed somewhat in the three data sets. Comparisons for DBP were limited to the age groups for which readings of DBP5 were available. For DBP5, only slight differences between the Spanish and International pools were observed (ages 6-18 compared), but these values were notably higher than those from the US (ages 13-18 compared). These findings suggest that the use of any particular age-based standard to evaluate readings in children in diverse populations cannot be recommended, at least until there is a better understanding of the true differences in BP between populations.

A profile of black and Hispanic subgroups' access to dental care: findings from the National Health Interview Survey.

This study examined which black and Hispanic minority subgroups were least likely to obtain dental care and why, based on logistic regression analyses of the 1986 National Health Interview Survey. Blacks and Hispanics were less apt to have private dental insurance coverage, to be knowledgeable about the purpose of fluoride, to have been to a dentist in the past year, and, when they did go, were more apt to have gone in response to symptoms rather than for preventive reasons, compared to whites. Logistic regression analyses for adults 18 years of age and older and for children and adolescents 2 to 17 years of age showed that the following individuals had the lowest probability of having been to a dentist in the past year: males, members of larger families, adults who were unemployed or in blue-collar jobs, those who lived in the South or nonmetropolitan areas, people who perceived their health to be fair or poor, and those with no private dental insurance. Mexican-Americans were least likely to have been to a dentist regardless of their income or education. In general, the findings confirmed the importance of dental insurance, as well as suggesting a need for more school-based dental programs and public health clinic-based dental health education and outreach efforts for targeting minority children and adults.

Promoting physical activity and a healthful diet among children: results of a school-based intervention study.

BACKGROUND: National health objectives call for improved diet and more regular physical activity among children. We tested the effects of a school-based program to improve students' diet and physical activity behavior at school. METHODS: Two of the four elementary schools in one Texas school district were assigned to intervention and two to control conditions. The three intervention components were classroom health education, vigorous physical education, and lower fat, lower sodium school lunches. Nutrients from school lunches and the total day and the amount of physical activity students obtained during physical education were assessed as outcome. RESULTS: Analysis of school lunches showed declines from base line to posttest in the two intervention schools of 15.5% and 10.4% for total fat, 31.7% and 18.8% for saturated fat, and 40.2% and 53.6% for sodium; posttest values were lower in the intervention schools. Observation of physical activity during physical education classes indicated an increase in the intervention schools from baseline to posttest in the percent of time children engaged in moderate-to-vigorous physical activity from less than 10% of class time at baseline to about 40% of class time at posttest; posttest values were higher in the intervention schools than in the control schools. CONCLUSIONS: This efficacy study demonstrates the feasibility of substantially modifying school lunches and school physical education to improve children's diet and physical activity behavior at school.

Dose-response relation of the angiotensin converting enzyme inhibitor ramipril in mild to moderate essential hypertension.

The effects of various dosage levels of ramipril on blood pressure were examined in a double-blind multicenter clinical trial. Patients with mild to moderate essential hypertension were first entered into a single-blind washout placebo phase of 4 weeks duration. The patients were then randomized to 1 of 3 treatment groups and received either 1.25, 2.5 or 5 mg of ramipril orally once a day for 6 weeks. After 6 weeks of treatment, the diastolic blood pressure had been decreased by 16.0 mm Hg (53 patients), 16.5 mm Hg (54 patients) and 19.9 mm Hg (53 patients) for the 1.25, 2.5 and 5 mg groups, respectively. Systolic blood pressure had decreased by an average of 22.5 mm Hg independent of the dose administered. Diastolic blood pressure was decreased to less than or equal to 90 mm Hg in 64%, 63% and 77% of the patients in the 3 groups, respectively. The differences in these percentages among the groups were not statistically significant. The tolerability of the drug was good; discontinuation of treatment was necessary for 1 patient in the 1.25 mg group and medication was lowered for 2 patients because of adverse reactions. There were no clinically significant changes of any laboratory variables, except for an increase in uric acid serum levels.

Living arrangements and dietary patterns of older adults in the United States.

Living arrangements and dietary patterns were examined for 3,477 adults aged 65 to 74 from the first National Health and Nutrition Examination Survey 1971 to 1974 (NHANES I). Several indicators of dietary variety, diet composition, and energy and nutrient intake from both the 24-hour recall, and the dietary frequency questionnaires were analyzed. Dietary patterns of older men were associated more strongly with type of living arrangement and income compared with older women. Men living with a spouse consistently had more favorable dietary patterns than either those living alone or those living with someone other than a spouse. Low income men who were not living with a spouse were at highest risk of poor dietary intake. Income was associated more consistently with the dietary indicators than type of living arrangement for women. Income, however, was still a less consistent influence on dietary patterns of older women compared to older men.

Effects of smoking on pulmonary function and symptomatology in occupationally exposed groups.

Records of 3006 employees of nine companies in southeast Texas screened by a local lung association during the years 1974-1975 were examined to assess the effect of smoking, age, and occupational and residential ambient air pollution exposure. The effects of smoking and occupational exposure were strong when tested against a respiratory morbidity response questionnaire considered to be diagnostic for early-stage bronchitis. Occupational exposure lost statistical significance after place of residence was controlled in the analysis. Smoking and age variables exhibited significant effects when the response variable was pulmonary function test results. The differences between questionnaire and pulmonary function test results may indicate early-stage vs. later-stage respiratory morbidity ascertainment. Agreement in classifying "abnormal" subjects with these two methods decreased with increasing levels of smoking.

DRGs in psychiatry. An empirical evaluation.

On October 1, 1983, Medicare began paying general hospitals by a prospective payment system based on DRGs. Psychiatric settings are exempted automatically or by request. By January 1985, however, a decision is required on how to integrate psychiatric settings into this system. This article provides an empirical analysis of the current DHHS DRGs categories for mental disorders. Current mental disorder DRGs and alternate DRGs examined here explain less than 3-12% of the variation in psychiatric length of stay. This is in contrast to 30-50% explained variation for other disorders. Alternatives and policy implications are discussed.

Diagnosis-related groups for mental disorders, alcoholism, and drug abuse: evaluation and alternatives.

Under the new federal prospective payment system, 15 of the 467 diagnosis-related groups (DRGs) cover mental disorders, including alcohol and substance abuse. The authors compare these 15 DRGs with some criteria of an ideal patient classification system. According to their assessment, the DRGs for mental disorders pose no administrative problems, but are not sufficiently homogeneous within categories or heterogeneous between categories. The authors conclude by discussing their own attempt to develop alternative DRGs, based on such variables as age, marital status, and type of treatment as well as on diagnosis.

Investigation of nonresponse bias in NHANES II.

In the second National Health and Nutrition Examination Survey (NHANES II), there was a 27% nonresponse rate in the examination phase. This report investigates the potential bias in these data due to this large nonresponse rate. Data from a household and medical history interview are used in the investigation of factors related to examination status. In addition, data from the examined group are compared to data from the 1976 National Health Interview Survey (NHIS). Since there was only a 3.7% nonresponse rate for the 1976 NHIS, proportions calculated from these data represent reasonable estimates of the true population values. Several variables have a significant association with the interview and examination status. However, it appears that the nonresponse and poststratification adjustments performed by the National Center for Health Statistics have removed most of these factors as sources of bias. There is excellent agreement in the marginal distribution of variables between NHANES II for examined persons and the 1976 NHIS.

Indicators of response to a mass media CPR recruitment campaign.

Respondents to a mass media cardiopulmonary resuscitation (CPR) recruitment campaign in Harris County, Texas were more likely than non-respondents to be White, female, and under 45 years of age, to have had previous CPR training, experienced an incident in which knowledge of CPR might have been useful, or to have a friend or relative with a relevant medical history. The majority of the respondents were housewives, and professionals or technical workers, particularly in the health field. Findings can be used to identify audiences for future mass media CPR campaigns.

Relationship between dietary and biochemical measures of nutritional status in HANES I data.

Data from the first National Health and Nutrition Examination Survey were examined for individual 24-h dietary intakes of protein, vitamin A, thiamin, riboflavin, and iron, and for laboratory indices of the same nutrients in blood and urine. Mean intake values were close to or above reference standards for all nutrients except iron. Substandard laboratory values were recorded for: serum albumin and vitamin A--less than 3% of subjects; urinary thiamin/creatinine excretion--3 and 8% of white and Black subjects, respectively; Hb, hematocrit, and percentage transferrin saturation--5 to 15% of whites and 18 to 27% of Black subjects; serum iron--less than 6% of subjects. Individual dietary recall data were of limited value in predicting the laboratory indices; regression analyses indicated that sociodemographic variables may be of greater predictive value.

Catastrophic health insurance and HMO's.

The catastrophic health insurance bills introduced during the 96th U.S. Congress failed to consider the current role that Health Maintenance Organizations (HMO's) play in providing catastrophic protection and the potential negative impact such legislation may have on their competitive position. This article demonstrates that HMO's are providing this coverage by using the simulated health care expenditures for families in one HMO. The estimated proportion of families that incur catastrophic expenditures varies from 0.3 to 14.4% depending on the definition used for catastrophic. The paper closes with a discussion of the potential adverse impact that the legislation would have had on HMO's.

Leisure behavior and attitudes toward leisure of alcoholics and nonalcoholics.

Alcoholics participated in fewer leisure activities than did nonalcoholics except that white-collar alcoholics participated in more leisure activities than did white-collar nonalcoholics. Alcoholics viewed leisure less positively than did nonalcoholics.