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PubMedDate not supplied

[Nursing research: a reality or an omen? The case of acute myocardial infarct. The GISSI Nursing working group].

Research articles on AMI patient, published on the nursing journals indexed in the Index Medicus were reviewed, to focus on the relevance and methodological reliability of aims, size of the samples, design, instruments used. Some comments on the problems and limits of nursing research in this special area are presented, in the perspective of planning a major collaborative study.

Clinical Nursing Research↗
PubMed1991

Xerophthalmia in Ethiopia: a nationwide ophthalmological, biochemical and anthropometric survey.

A total of 6636 children, aged from 6 months to 6 years and selected throughout the country using a multi-staged stratified sample design, were examined for signs of xerophthalmia. The concentrations of retinol and of beta-carotene were measured in 742 children, including those with xerophthalmia and every twentieth of the remaining children. Anthropometric measurements were made on 2909 of the children. Bitot's spots were seen in 1.0% of all children, with a higher prevalence in the pastoral (1.6%) and cropping (1.1%) agro-ecological zones than in the zones characterized by cash crops (0.4%) and 'ensete' (false banana, Ensete ventricosum) (0.0%). One case of corneal xerosis and 2 cases of corneal scar were also seen. Serum retinol levels were in the 'deficient' range (less than 0.35 mumol l-1) in 16% and 'low' (0.35-0.69 mumol l-1) in 44% of children. Serum retinol and clinical signs did not show any correlation with occupation and education of head of household, household size or anthropometric measurements. More stunting than wasting was observed, with peak prevalence of these signs of malnutrition being observed in the second year of life.

Agriculture↗
PubMed1991

[Health status of urban passenger transportation conductors in Mexico City].

Between 1985 and 1988, a two-phase epidemiological study was conducted at the "Ruta 100" company in Mexico City to examine the harmful effects of the working conditions on drivers of urban transport vehicles. In the first phase, five groups of nine drivers each were interviewed regarding their opinions about their working conditions and possible work-related disorders. On the basis of this information, an epidemiological survey was developed and applied using a polytypic sampling design to some 200 drivers plus two other groups of approximately the same size, one consisting of maintenance workers and the other of office workers, which served as controls. The driver group showed a high prevalence of respiratory and neuropsychiatric disorders, diarrhea, myopia, arterial hypertension, urinary disorders, hemorrhoids, hearing loss, back pain, varicose veins, peptic ulcers, diabetes, cardiopathies, abdominal hernias, and appendicitis. For arterial hypertension, hemorrhoids, nervous disorders, and psychiatric disorders the prevalence ratios of drivers/maintenance workers and drivers/administrative workers were statistically significant.

Adult↗
PubMed1990

The effect of retrospective sampling on binary regression models for clustered data.

Recently a great deal of attention has been given to binary regression models for clustered or correlated observations. The data of interest are of the form of a binary dependent or response variable, together with independent variables X1,...., Xk, where sets of observations are grouped together into clusters. A number of models and methods of analysis have been suggested to study such data. Many of these are extensions in some way of the familiar logistic regression model for binary data that are not grouped (i.e., each cluster is of size 1). In general, the analyses of these clustered data models proceed by assuming that the observed clusters are a simple random sample of clusters selected from a population of clusters. In this paper, we consider the application of these procedures to the case where the clusters are selected randomly in a manner that depends on the pattern of responses in the cluster. For example, we show that ignoring the retrospective nature of the sample design, by fitting standard logistic regression models for clustered binary data, may result in misleading estimates of the effects of covariates and the precision of estimated regression coefficients.

Cluster Analysis↗
PubMed1990

Accuracy of Medicare reimbursement for cardiac arrest.

Diagnosis related group (DRG) 129 consists exclusively of discharges having a principal diagnosis of International Classification of Diseases, Ninth Revision, Clinical Modification code 427.5 (cardiac arrest). It excludes patients with more specific diagnoses (eg, myocardial infarction and arrhythmia) or patients admitted for a different reason and who subsequently experience cardiac arrest. This study used a one-stage sample design to select all DRG 129 discharges from random hospitals, stratified by their annual number of DRG 129 bills. Using blinded techniques, medical records specialists reabstracted the International Classification of Diseases codes for 857 medical records. For the bills that were not coded DRG 129 on reabstraction, physicians classified the incorrect bills by clinical situation and reason for error. Diagnosis related group 129 had significantly higher rates of coding errors and upcoding than other DRGs. Of discharges erroneously billed to DRG 129, 42.1% of the patients entered the hospital for heart disease other than cardiac arrest and 55.2% died after entering the hospital for other diseases. Attending physicians need to distinguish between the "immediate cause" of death for the death certificate and the "principal diagnosis" for reimbursement purposes.

Cause of Death↗
PubMed1990

Sister chromatid exchanges induced in peripheral lymphocytes of workers exposed to low concentrations of styrene.

This study employed a longitudinal sampling design to obtain measurements of exposure and exhaled air from all members of a cohort several times over the course of one year. Styrene in exhaled air correlated well with styrene in breathing zone air. Both smoking and exposure to styrene appear to have contributed significantly and separately to increased SCEs. Early results imply that SCEs were somewhat more highly correlated with styrene in exhaled air than in breathing zone air.

Adult↗
PubMed1989

Who hasn't heard about AIDS?

This article analyzes who among the general population has not heard about AIDS despite intensive educational programs and widespread media attention about the syndrome. The data are drawn from a survey of the general public's knowledge, attitudes, and behavior toward AIDS in May-July, 1987 to establish a baseline for future educational interventions and to identify groups in need of special educational efforts. A total of 1540 interviews were conducted in Chicago and the surrounding six-county metropolitan area with adults between the ages of 18 and 60 in a two-stage cluster sample designed to compare blacks, whites, and Hispanics. Of the 1540 respondents, 49 (3.2%) had never heard of AIDS. Contingency table and logistic regression analyses indicated that lower educational levels and being Hispanic or Asian predict not having heard about AIDS. The results suggest the need for programs and intervention strategies that consider the special characteristics of these populations.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Chronobiologic quantification of nocturnal low-dose dopamine effect on circadian rhythms of thyroid-related hormones and prolactin (PRL).

Six clinically-healthy young men provided plasma samples every 30 min for 24 h (from 09:00-09:00 on 2 occasions. TSH, free T3 and free T4 were determined in the 30-min samples, while prolactin was determined in samples 1-3h apart. During the first test span, each man received an infusion of physiologic saline between 21(00)-01(00). Upon re-sampling several weeks later, 3 men received a low dose of dopamine (0.1 microgram/kg/min) and 3 men received a high dose (1.0 microgram) over the same hours (21:00-01:00). The least-squares fit of a 24-h cosine to each data series described a statistically-significant circadian rhythm (p less than 0.01) for each subject on each day of study. While overall group comparisons revealed no significant difference in mesor for any hormone studied, some intra-individual differences in rhythm parameters between saline and dopamine infusion were found. Dopamine Rx produced a statistically-significant increase in amplitude for PRL and T4 and an advance in acrophase for TSH, T3 and T4, but a delay for PRL. Studies measuring hormones of interest for the 24th immediately preceding and the 24th immediately following dopamine infusion at varying circadian stages (rather than only between 21:00-01:00) are warranted and have to be individualized--one of the points of this paper. The other main point is that data reduction to a mean and a standard deviation entails loss of information that can be recovered by chronobiologic methods, here used only as a model, in view of the limitations of the sampling design on hand.

Circadian Rhythm↗
PubMedDate not supplied

Contraceptive practice and fertility in Thailand: results of the Third Contraceptive Prevalence Survey.

The Third Contraceptive Prevalence Survey in Thailand was conducted in 1984. Results indicate a continuation of the rapid rise in contraceptive use among married couples that has been taking place over the past 15 years. Prevalence levels are approaching those common in economically advanced countries. Sterilization is now the most common method, although a fairly broad range of other methods is also widely used. Only modest levels of unmet need for contraception for either limiting family size or spacing children now exist. Fertility rates have fallen since the previous survey, done three years earlier, but to a lesser extent than would be expected from the increased use of contraceptives. Family size preferences are concentrated at small family sizes. A comparison between the Buddhist majority and Moslem minority, made possible through a special sample design, reveals substantial differences between the two groups. Contraceptive use is lower and fertility levels and preferences are higher among Moslems than among Buddhists.

Adolescent↗
PubMed1985

Partial hospitalization. An alternative to inpatient care.

Despite problems with research designs, sample sizes, differing areas of focus, and various research instruments, psychiatry can be encouraged by studies pointing to the following: Partial hospitalization can offer a viable alternative to inpatient hospitalization with less stigma and less family burden for patients. Such patients fare as well or better than their inpatient counterparts. When families or stable living situations are not available, the most acute patients can be treated and housed in a supervised living situation. Social and familial roles can be maintained. Partial hospitalization is helpful in reducing length and expense of full-time hospitalization when used as an transition to more traditional outpatient treatment and community life. This does not lead to increased rates of readmission or to exacerbating other symptoms or pathology. Partial hospitalization has grown steadily in the past 20 years. The question is no longer whether partial hospitalization works, but "what kind of patient can be best treated by partial hospitalization?" Innovative programs are sprouting. The 1980s bring fiscal, educational, and clinical challenges to partial hospitalization programs everywhere.

Community Mental Health Centers↗
PubMed1984

A two-year dietary survey of middle-aged women: repeated dietary records as a measure of usual intake.

A two-year survey of the dietary consumption and supplement use patterns of adult women was conducted at the University of Wisconsin-Madison. Participants were asked to record their diet on two randomly selected days per month over a two-year period. Each subject filled out an average of 19 records a year, for an overall 71% return rate. Because of the sampling design, it was possible to estimate each woman's "usual" or average daily dietary and total intake (diet plus supplements) of 15 nutrients. Many women were consuming usual amounts of energy, calcium, iron, magnesium, vitamin B-6, and, especially, zinc and total folate that were 30% to 50% below recommended levels. It was also found that the women generally took vitamin/mineral supplements for nutrients already adequately supplied in the diet. Low nutrient intakes may have been due, in part, to underreporting of food intakes.

Adult↗
PubMed1984

Morphometric studies of the epidermal-dermal junction in the rat ear: some effects of experimental friction on epidermis and anchoring fibrils.

The aim of this investigation was to determine whether, following the application of experimental friction to the skin, qualitative an quantitative differences could be induced in the epidermis and in anchoring fibrils. The skin of rat ears was subjected to repeated mild fractional stimulation with a rotating bristle brush moistened with saline thrice weekly for three weeks, untreated ears being used as controls. A stratified random sampling design was followed for the morphometric analysis of interfollicular epidermis. With the light microscope, the lengths of the granular cell/keratin (BGK) and epithelial-connective tissue (BEC) junctions were measured using an image analyser, as was the epithelial thickness (T). The ratio BEC/BGK provides an index of the degree of irregularity of the epithelial-connective tissue junction. Using electron microscopy, the numbers of anchoring fibrils per unit length of lamina densa (NB) were determined using stereological intersection counting. There are no significant differences in BEC/BGK or T between control and experimental groups, but anchoring fibril frequency NB increased from 10.29 micrometers in control epidermis to 18.9 micrometers in friction-treated epidermis. It is concluded that a mild frictional stimulus which fails to produce significant alterations in epidermal thickness can produce a marked increase in anchoring fibril frequency. This response may reflect a functional alteration associated with increased mechanical loading, in which epidermal-dermal adherence is augmented by either synthesis of anchoring fibrils or their insertion into the lamina densa.

Animals↗
PubMed1980

[Drug monitoring: psychological methods (author's transl)].

Drug related mental and psychophysiological disturbances may be assessed by the same instruments of observation, ratings and self-ratings used for assessment of the efficacy of psychotropic drugs. Several possible sources of bias, however, concerning survey design, sample selection and evaluation and interpretation of data on adverse drug reactions have to be identified by careful documentation in order to exclude confounding factors, such as type and severity of treated and additional diseases, external events, personal factors in perception of symptoms by patient and physician.

Humans↗
PubMed1981

Integrating ethnographic research with nutrition studies.

A major methodological problem is dietary intake research is the specification of an adequate sampling design. Ethnographic research provides the investigator with essential data for more effective research design by establishing sources of temporal variation in food intake and by identifying significant consumption settings and main sociocultural characteristics affecting intracommunity differences in foot intake. A checklist of sources of temporal variation commonly found in various societies is presented as a guide for ethnographic work. Other uses of ethnography to improve dietary intake methodology are the identification of culturally and socially sensitive aspects of food use and the provision of background information for the interpretation of research results.

Anthropology, Cultural↗
PubMed1980

The non-emergency in the emergency room.

During designated sampling periods, all patients presenting at an urban hospital Emergency Room with complaints meeting nonurgent criteria were interviewed in an effort to examine patterns of Emergency Room usage and to characterize those patients utilizing the Emergency Room inappropriately. Each such patient's stated number of visits to an Emergency Room during the previous year, including the present visit, was used as an indicator in assessing inappropriate Emergency Room use. Statistical analysis showed no significant differences when the variable was race; in contrast, significant differences were seen when the variables were type of medical insurance coverage and personal physician status. Based on these data, we suggest that the true problem is not one of how to control inappropriate Emergency Room use, but rather one of how to improve the health care delivery system for the urban poor.

Adult↗
PubMed1995

Cyclic AMP and glycerol concentrations in freeze-clamped human omental and subcutaneous adipose tissues.

OBJECTIVE: To compare intracellular concentrations of cyclic AMP, GTP, ATP, AMP and glycerol in omental and abdominal subcutaneous adipose tissues. DESIGN: Samples of omental and/or abdominal subcutaneous adipose tissues of 14 women undergoing elective surgery were freeze-clamped, deproteinized with perchloric acid and neutralized. All subjects were obese since it was not possible to freeze-clamp lean individuals. MEASUREMENTS: The concentrations of ATP and GTP were determined by ion-paired high performance liquid chromatography and AMP and glycerol enzymatically. Cyclic AMP was determined by radioimmunoassay. Intracellular nucleotide concentrations were calculated from tissue weights, water contents and relative amounts of sodium and potassium. RESULTS: The intracellular concentration of cyclic AMP in omental adipose tissue (31 mumol/l) was twice as high as that in subcutaneous fat while those of ATP, GTP and AMP were similar at the two sites. Glycerol concentrations were higher in subcutaneous (472 mumol/l) than in omental (325 mumol/l) adipose tissue. CONCLUSION: The results suggest higher relative stimulation of lipolysis by cyclic AMP in omental adipose tissue than in the subcutaneous region in situ. However, probably because of differences in blood flow and possibly in the lipolytic machinery, this is not reflected as a higher glycerol concentration.

Adenosine Monophosphate↗