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PubMedDate not supplied

The Delphi methodology (Part one): A useful administrative approach.

The Delphi methodology is used to determine, predict and explore group attitudes, needs and priorities. This paper, the first of a two part series on the Delphi methodology, will provide nurse administrators with the basic information necessary to participate in and conduct projects using the Delphi methodology. The methodology will be defined and issues related to design, sampling, instrumentation and methods of data analysis discussed. The role of the nurse administrator, when the Delphi methodology is used, will then be addressed. In the second paper, administrative applications of the Delphi methodology will be addressed.

Delphi Technique↗
PubMed1975

Distribution of bromouracil in the pyrimidine oligonucleotides of Drosophila DNA.

DNA was isolated from Drosophila melanogaster larvae fed radioactive thymidine (TdR), bromodeoxyuridine (BUdR), or one of these nucleosides together with 5-fluorouracil (FU) under identical conditions. The four DNA samples designated T-DNA, B-DNA, T(F)-DNA, and B(F)-DNA respectively were hydrolyzed with formic acid-diphenylamine, and the pyrimidine oligonucleotides of various chain lengths (isotichs) were ractionated by DEAE-celluclose chromatography. The distributions of the labeled thymine and bromouracil (BU) residues among the pyrimidine isostichs were determined, and compared for the four DNAs. These comparisons indicated the following: (1) Similarity of T-DNA and T(F)-DNA with respect to labeled thymine distribution among the pyrimidine isostichs (using the mononucleotide to pentanucleotide tracts for statistical comparisons) showed that TdR entering DNA synthesis via the salvage pathway has the same distribution whether the synthetic pathway is operating normally or is inhibited by FU treatment. (2) Quantitative comparison of the distribution of BU among the isostichs of B-DNA and B(F)-DNA with the distribution of labeled thymine in T-DNA showed significant differences, indicating that the organism does not accept BUdR indiscriminately at all thymine sites for DNA synthesis. (3) Comparison of the distribution of BU in B-DNA and B(F)-DNA showed that isostichs 1 and 3 differ significantly. The elution profiles of the isostichs also differed qualitatively between these DNAs. This analysis confirms differential incorporation of BUdR into Drosophila DNA in the presence of a thymidylate inhibitor. The observations on BUdR incorporation in Drosophila DNA have been discussed with relation to the high frequency of somatic cell mutations induced in imaginal disc cells by treatment with the analog in the presence of inhibitors of thymidylate synthetase.

Animals↗
PubMed1993

[Prevalence of Neisseria meningitidis carriers in a school population in the metropolitan area of Madrid].

The prevalence of healthy carriers of Neisseriae meningitidis has been addressed by studying oropharynx samples of 1,172 schoolchildren in Madrid. The sample design took into consideration social status, age and sex. The total prevalence of healthy carriers was 2.30%, with 66% or these in the six year old age group (RR = 2.88, p < 0.005). Serotype B was found in 74% of the carriers, again mainly in the six year old age group, and 18.5% were serotype A, with most of them being found in the fourteen year age group. Serotype A carriers were females in 80% of the cases (p = 0.04). Serotype C was only found in six year old males. The prevalence of healthy carriers of Neisseriae meningitidis in our school-age population, in a non-epidemic situation, is in accord with results reported from other countries around us and agrees with previous reports of a higher prevalence among younger children and in males. In addition, the association between sex and some serotypes is confirmed.

Adolescent↗
PubMed1993

Measurement error in alcohol consumption: the Swiss Health Survey.

It is planned to include in the Swiss Health Survey (SHS) the questions on the consumption of alcohol that have been part of the Trend Surveys of the Swiss Institute for the Prevention of Alcohol and Drug Problems (SIPA). Since both surveys use different questioning methods (SHS: telephone interview/self-administered questionnaire; SIPA Trend Surveys: personal interviews) a comparative study was carried out to test possible effects of the methods used on responses about alcohol consumption. A split-sample design was used, whereby 1097 persons were asked about their alcohol intake by personal interview, and 1154 persons completed a self-administered questionnaire with the same questions. Considerable differences were found: on an average, consumption reported by personal interview was 38.5% higher among males (including abstainers: 35.9%) and 18.0% higher among females (including abstainers: 17.4%) than that reported by self-administered questionnaire. Consumption figures as assessed by personal interview correspond better to the per capita consumption figures as estimated by sales. Preliminary conclusions concerning the design of future surveys of alcohol consumption in Switzerland are presented.

Adolescent↗
PubMed1993

Epidemiologic assessment of risks of adverse reactions associated with intermittent exposure.

Measures of risk of adverse reactions, such as the absolute risk, the relative risk, and the excess risk, are analyzed for individuals who are exposed occasionally for periods of varying duration. This type of exposure is of particular importance for the epidemiologic assessment of drug safety. A Poisson point process model that allows for the simultaneous consideration of concomitant factors is derived for the estimation of the hazard rates. The model can judge acute adverse reactions and is applicable not only for rare risks since an undesired effect may occur repeatedly for an individual. Hazard estimation is achieved with the aid of the maximum likelihood method for several sampling designs, such as cohort studies, case-cohort studies, and case studies. In the latter design only those individuals who have had an adverse reaction during the time of observation are considered for hazard estimation. An application to the analysis of wound-healing impairments is given.

Case-Control Studies↗
PubMed1995

[The prevalence of the principal cardiovascular risk factors in the population of the Azores].

STUDY OBJECTIVE: to characterize the high mortality rate by ischemic heart disease in Azores, by evaluating the main coronary heart disease risk factors prevalence in the population. DESIGN: sample study referring the population of 5 islands: 37 counties. Aleatory choose in the electoral lists. SETTING: the selected individuals were convocated by mail to show up at the Hospital for evaluation. PATIENTS: 1089 individuals selected by aleatory choose from the electoral lists. INTERVENTIONS: the sample was stratified regarding rural (R) and urban (U), by sex feminine (F) and masculine (M), age 20-40 and 40 to 60 years old. All of them were determined three values of blood pressure, and was taken for exact value the medium of the three, inquired the smoking habits and serum lipids were determined. We considered risk factors (RF); blood pressure > 140/90 mmHg, total cholesterol > 200 mg/dl, HDL cholesterol < 35 mg/dl, triglycerides > 180 mg/dl and smoking habits were stratified in three scores: 1: 1-10, 2: 11-20, and 3: more than 20 cigarettes a day. MAIN RESULTS: total prevalences; HBP 20.4%, smoking habits 33%, total hypercholesterolemia 47.3%, low HDL cholesterol 17.4% and triglycerides 30.5%. CONCLUSIONS: the values found for total cholesterol, triglycerides and smoking habits were high and superior to the national medium and to those found in reference studies. Preventive strategies are pointed out.

Adult↗
PubMedDate not supplied

Support among smokers and nonsmokers for restrictions on smoking.

The responses of 387 smokers and 988 nonsmokers obtained in a population-based survey in Ontario, Canada, were compared with regard to knowledge, attitudes, and predicted behavior concerning restrictions on smoking. Responses were tabulated as percentages and weighted according to the sample design. Nonoverlapping 95% confidence intervals provided evidence to reject the null hypothesis. Although smokers were found to be less knowledgable about the health effects of smoking and environmental tobacco smoke, more than 90% of both smokers and nonsmokers agreed with restrictions on smoking in 14 specific settings; for some settings, they disagreed on the extent of restrictions. The groups differed concerning specific bans on cigarette sales, but support was uniformly strong for bans in hospitals, controls on vending machines, and enforcement of the law prohibiting sales to minors. Clear majorities of both groups agreed that local government should enact and enforce restrictions. Smokers were more likely than nonsmokers to predict that smokers would comply with more restrictions, and most smokers indicated that they, themselves, would comply. We conclude that general health education should be bolstered by strategies specifically targeted at smokers. There is a strong basis across the population for restrictions to reduce exposure to environmental tobacco smoke; support for the role of local government in this regard is clear. Noncompliance with more restrictions is unlikely to present enforcement problems. Measures limiting the physical access of youths to tobacco will be widely supported, but strategies to increase support for tax measures are needed.

Adult↗
PubMed1995

Incorporating toxicity considerations into the design of two-stage phase II clinical trials.

Phase II study designs are proposed that evaluate both clinical response and toxicity, and that are similar in structure to Simon's two-stage designs. Sample sizes and decision criteria are chosen to minimize the maximum expected accrual, given that the treatment is unacceptable either in terms of clinical response or toxicity. This is achieved subject to control of error rates, either uniformly over all possible correlation structures linking response and toxicity, or alternatively, under an assumption of independence between response and toxicity. In the latter case, bounds on the error rates show that effective control is still uniformly achieved even if the independence assumption is relaxed.

Biometry↗
PubMed1996

Needle wire localization for nonpalpable breast lesions: sensations, anxiety levels, and informational needs.

PURPOSES: To determine the sensations that women most frequently report during needle wire localization (NWL) for nonpalpable breast lesions, to rate preprocedure anxiety, and to describe what preparation women consider desirable for the procedure. SETTING: Outpatient breast center in a large, not-for-profit hospital in a major city in Texas. DESIGN: Prospective, descriptive design. SAMPLE: Nonprobability sample of 56 women who were an average of 57 years old (range = 30-87 years). Forty-three (77%) underwent single wire localization. Nine (16%) of the women were subsequently diagnosed with breast cancer. METHODS: Subjects provided demographic information preprocedure. Postprocedure, subjects described and rated intensity of sensations on a 0-10 verbal, numeric rating scale. Preprocedure anxiety was also rated. Subjects responded to the question "What would you have liked to have been told before NWL to best prepare you for the procedure?" FINDINGS: Most frequently reported sensations were pressure, stinging, and pain, which averaged 6, 4, and 7, respectively, in intensity. Mean anxiety score was 5.3 on a scale of 10 with 10 subjects rating their anxiety as 10. Five (9%) subjects fainted during the procedure. Subjects provided valuable suggestions about how to prepare patients for this procedure, such as providing brochures and pictures about the procedure. CONCLUSIONS: Subjects are moderately or highly anxious before NWL of the breast and describe a variety of sensations. Risk factors for fainting during this procedure and strategies to prevent fainting must be determined. IMPLICATIONS FOR NURSING PRACTICE: Sensory information should be used to prepare women for NWL. Subjects' suggestions about how to prepare women for the procedure can be used to develop educational and sensory approaches to enhance preparation for the procedure and perhaps reduce anxiety.

Adult↗
PubMed1996

Do historic studies of fish consumers support the widely accepted LOEL for methylmercury in adults.

Lack of demonstrated neurotoxicity among fish-eating populations has been cited by the World Health Organization and others as supporting an adult LOEL (lowest observed effect level) of > or = 200 ppb blood mercury equivalent. We reviewed 13 published evaluations of neurologic status as related to tissue mercury or methylmercury concentration in long-term fish-eating populations. Review criteria included study size, design (sampling strategy, characterization of exposure, characterization of outcome) and data analysis. No case of classic Minimata disease is described in the 13 studies. Also, no study clearly shows a threshold tissue level above which any form of neurologic dysfunction occurs. A study by Valciukas et al. shows no evidence of neurologic impairment in groups with blood mercury of 10-20 ppb. Studies by Spitzer et al. and McKeown-Eyssen and Reudy suggest correlation of neurologic dysfunction with rising blood mercury concentrations in the 60-120 ppb range. While other studies show no effects associated with rising mercury dose, numbers are small, participant self-selection likely and the clinical assessment limited. Together the 13 studies describe neurologic examinations in approximately 50 fish eaters having a blood mercury equivalent above 200 ppb; of these subjects, neurologic dysfunction consistent with methylmercury exposure was found in as few as six and as many as 15. We conclude that the oft-cited LOEL for (methyl)mercury of 200 ppb in blood is not supported by these studies.

Animals↗
PubMedDate not supplied

Predictors of nutritional supplement use by the elderly.

We conducted a population survey to describe patterns and determine predictors of the use of nutritional supplements and single-ingredient vitamins and minerals among elderly living in five adjacent urban and rural counties in the Piedmont area of North Carolina. The stratified random sample consisted of 3939 black and white participants age 65 or older from the Duke Established Populations for Epidemiologic Studies of the Elderly. The use of nutritional supplements within the previous 2 weeks was determined during an in-home interview. Multivariate analyses, using weighted data adjusted for sampling design, were conducted to assess the association between nutritional supplement use and predisposing, need, and enabling factors. Nutritional supplement use was reported by 26.2% of participants and was more likely for those who were white women, were high school educated, were underweight, took prescription drugs, had five or more health visits in the previous year, and had supplemental health insurance. It was less likely for those with poor self-rated health. The majority (71.5%) of nutritional supplement users took at least one single-ingredient supplement. Use of such products was more likely in those who were white, born and raised in an urban area, and high school educated, and was less likely in those with impaired functional status. Nutritional supplement use is prevalent in community-dwelling elderly and is more commonly associated with demographic factors and access to health care than with need factors.

Aged↗
PubMed1997

Pharmacologic management of heart failure among older adults by office-based physicians in the United States.

BACKGROUND: Despite the recent availability of new classes of heart failure medications, little is known about national patterns in the actual physician utilization of these drugs. METHODS: In the National Ambulatory Medical Care Survey, 2912 US physicians reported on 16,968 office visits in 1991-1992 with patients aged > or = 65 years. National estimates were obtained from weighted results that accounted for the complex sampling design. RESULTS: An estimated 8.3 million (2.6%) office visits with older adults involved heart failure. This included 9.3% of visits to cardiologists, 4.3% to internists, 3.5% to general and family physicians, and 0.6% to other physicians. The most frequently prescribed medications during visits with these patients were diuretics (69%), digitalis compounds (46%), angiotensin-converting enzyme inhibitors (30%), and nitrates (19%). Internists and general and family physicians prescribed angiotensin-converting enzyme inhibitors, digitalis compounds, and loop diuretics for patients with heart failure less often than did cardiologists. CONCLUSIONS: These are the first national surveillance estimates of physician practices in the management of heart failure. These data were collected during the same period in which heart failure clinical trial results were initially published, and they provide a baseline for monitoring the influence of recent clinical practice guidelines and professional education on changes in the management of heart failure by primary care physicians.

Aged↗
PubMed1996

Quality of life and pharmaco-economic aspects of obsessive-compulsive disorder. A South African survey.

OBJECTIVE: The quality of life and pharmaco-economic aspects of obsessive-compulsive disorder (OCD) have received relatively little research attention to date. We aimed to gather preliminary data on these in a South African patient sample. DESIGN: A survey of members of the Obsessive-Compulsive Disorder Association of South Africa was undertaken by means of a detailed self-report questionnaire. RESULTS: Results of the survey suggest that OCD causes significant morbidity, leading to clear distress and Interference with academic, occupational, social and family function. Unfortunately, correct diagnosis and appropriate treatment have been delayed in many patients, and the financial costs of such incorrect management are likely to be considerable. CONCLUSION: Much further work needs to be done by the medical profession and by interested consumers to raise awareness about OCD and to provide information about its management. In South Africa, it is particularly Important to undertake such psycho-education at a primary health care level and to impact on patients of low socio-economic status.

Activities of Daily Living↗
PubMed1997

Estimation of absolute risk from nested case-control data.

Benichou and Gail (1995, Biometrics 51, 182-194) describe methods for estimating the absolute risk of developing disease given a set of covariate values over a specified time interval from a case-control study within a cohort. The methods are most suitable for unmatched case-control studies, and are restricted to categorical covariates. Expanding on methods for estimating relative mortality from nested case-control studies presented in Borgan and Langholz (1993, Biometrics 49, 593-602), we present methods for estimating absolute risk from individually matched nested case-control data. These methods accommodate continuous and time-dependent covariate histories, the sampling of cases, and various control sampling designs.

Adult↗
PubMed1997

[Children from the GAZEL cohort: II--motive for contact with the medical-educational system by age and sex].

An epidemiological survey of 2582 French children aged 4 to 16 has been conducted to assess patterns of service use in relation to psychological disturbances. Details on the design, sample, survey instruments, response rate, and 12-months prevalence rates of contacts with a range of different professionals were presented in a previous article. In this second article, the psychological motives leading to contact with family doctors, school-based professionals, speech and language therapists, and mental health specialists are analyzed. The age and gender effects are assessed for each motives. On the whole, consistent sex differences were found for the types of complaints presented by service users, with emotional symptoms being more frequent amongst girls, and behavioural, developmental and learning difficulties being more frequent amongst boys. Mental health specialists were attended for a variety of reasons. Family doctors were contacted for minor emotional difficulties. Because family doctors were consulted by a high proportion of children and adolescents of our sample, the role of this professionals in the detection and management of minor psychological morbidity is emphasized.

Adolescent↗
PubMed1997

Continuity of care and the use of breast and cervical cancer screening services in a multiethnic community.

OBJECTIVE: To examine how continuity of care affects the use of breast and cervical cancer screening in a multiethnic population. METHODS: All data came from a structured telephone survey of a population-based quota sample designed to determine the cancer prevention needs of multiethnic blacks and Hispanics in New York, NY, in 1992. The study included 1420 women of 7 racial/ethnic groups: US-born blacks, English-speaking Caribbean-born blacks, Haitian blacks, and Puerto Rican, Dominican, Colombian, and Ecuadorian Hispanics. The main outcome measures were ever and recently having had a Papanicolaou smear, clinical breast examination (CBE), or mammogram. RESULTS: Among respondents who qualified for the survey on the basis of age and ethnicity, the refusal rate for completing the interview was 2.1%. Compared with women without a usual site of care, those with a usual site, but no regular clinician, were 1.56, 2.45 (P < or = .01), and 2.32 (P < or = .05) times as likely ever to have received a Papanicolaou smear, CBE, or mammogram, respectively and 1.84, 1.92 (P < or = .05), and 1.75 times as likely to have received a recent Papanicolaou smear, CBE, or mammogram, respectively. Compared with women without a usual site of care, women with a regular clinician at that usual site of care were 2.63 (P < or = .01), 2.83 (P < or = .01), and 2.30 (P < or = .05) times as likely ever to have received a Papanicolaou smear, CBE, or mammogram, and were 2.00 (P < or = .05), 2.65 (P < or = .01), and 1.40 times as likely to have recently received a Papanicolaou smear, CBE, or mammogram, respectively (adjusted odds ratios). For uninsured women, presence of a usual site of care was associated with increases in recent use of cancer screening for all screening tests. CONCLUSIONS: There is a linear trend in increasing breast and cervical cancer screening rates when one goes from having no usual source of care, to having a usual source, and to having a regular clinician at that usual source. Emphasis on continuity of care, especially on usual source of care, may help to bridge the gap in access to cancer prevention services faced by minority women.

Adult↗
PubMed1997

[The IBERPOC project: an epidemiological study of COPD in Spain. Scientific Committee of the IBERPOC study].

The aim of the IBERPOC study is to determine the prevalence of chronic obstructive pulmonary disease in Spain, to collect data on its management, the degree of variability in diagnosis, treatment and quality of life, and to estimate the mean annual direct health costs for these patients. IBERPOC is a multicentric transversal epidemiologic study that selects participants from populations corresponding to geographic and/or administrative areas using a probabilistic formula. Included are both males and females between 40 and 69 years of age who are residents in the study area and living outside institutions. This article describes the study design, sample selection criteria, the method and its application, and control systems used to prevent errors in patient selection and in pulmonary function testing. The schedule for data analysis is also included.

Adult↗
PubMed1997

[Smoking prevalence trends in Catalonia, Spain, 1982-1994].

BACKGROUND: Smoking prevalence trends from 1982 to 1994 of adult population in Catalonia (Spain) are described. SUBJECTS AND METHODS: Four population surveys have been carried out periodically using the same questionnaires and definitions for smoking status. Surveys in 1982, 1986 and 1990 have been implemented taking samples of Catalonia population through a multistage sampling with random stratified selection by province and habitat. Individuals were chosen through a random route process. In 1994, a survey with a complex probabilistic sample design with 8 geographical areas (health regions) and 2 basic units (towns and individuals) was implemented. RESULTS: Among the 15-64 years old adults, a decrease of 6.9% in smoking prevalence has been observed. The initial prevalence in 1982 was 37.9% (CI 95%: 35.4; 40.3); in 1994 this prevalence was 35.3% (CI 95%: 34.4; 36.2). In 1994, the prevalence of current smokers in population over 14 years old was 30.6% (CI 95%: 29.8; 31.4). We have observed a significant decrease in smoking prevalence in all age groups among male population (-20.6% for the 12-year period) whereas prevalence has increased among female (+28.0%) mainly among those between 25 and 54 years old. The main percentual decrease in smoking prevalence has been observed among young people aged 15-24 years old for both genders. The proportion of former smokers has remained stable (11.4% in 1982, 12.9% in 1994) during the period studied. The proportion of former smokers increases with age among man over 25 years. CONCLUSIONS: Smoking habit is still very prevalent in Catalonia, even higher than in other Western European countries. In spite of the increase among women, the significant dectines of smoking prevalence among men and youngsters (of both genders) could represent encouraging findings in order to pursue the efforts aimed at reducing the morbi-mortality burden of smoking in our society.

Adolescent↗