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At least 1,243 records · Page 69Linked to original sources

PubMed2006

[Identification of quality indicators of stroke care].

BACKGROUND/OBJECTIVES: The purpose of the present study was to identify existing quality indicators of stroke care and to select those that are appropriate for use in the German health care system. METHODS: A systematic literature search in databases of performance measures, clinical indicator programs, stroke guidelines and published scientific literature (published in 1993-2002) identified 151 quality indicators. This number was reduced by selecting indicators that satisfied the following quality criteria for clinical performance measures: a) consensus on the relative importance of aspects of clinical care (according to the American Heart Association/American College of Cardiology Forum), b) controllability of aspects of clinical care (according to the German "Advisory Council for the Concerted Action in Health Care") and c) internal validity (according to the stroke guideline of the Royal College of Physicians, UK). RESULTS: Of the 151 quality indicators, 31 fulfilled all three criteria for clinical performance measures. After elimination of overlapping indicators 13 quality indicators remained covering important aspects of the quality of stroke care in Germany: two of these indicators refer to the quality of structural aspects of care, six consider processes of care and five indicators are devoted to outcomes of care. These 13 indicators cover "prevention, rehabilitation, coordination and continuity of care", which are important controllable aspects of care. Whereas six indicators were considered to be highly valid, seven indicators did not convey enough information to ensure their validity. CONCLUSION: Suitable quality indicators covering several important aspects of stroke care could be selected from existing indicators for the development of an appropriate set of indicators to be used in the German health care system.

Activities of Daily Living↗

PubMed2006

Clinical outcomes with drug-eluting stents following atheroablation therapies.

BACKGROUND: Prior studies of atheroablation (directional atherectomy, rotational atherectomy and laser angioplasty) have demonstrated either no advantage or worse outcomes relative to conventional balloon angioplasty. Because these techniques are still required in a minority of patients, we hypothesized that the use of drug-eluting stents (DES) would minimize the rate of major adverse cardiac events (MACE) after atheroablation. METHODS: From 2,252 percutaneous coronary intervention procedures, 212 patients were extracted using case control matching and were analyzed to compare the rate of MACE across four groups (DES with atheroablation, bare-metal stent (BMS) with atheroablation, DES without atheroablation, bare-metal stent without atheroablation). A Cox proportional hazards model was constructed to determine predictors of MACE after adjustment for potential confounders. Internal validation was performed with bootstrapping. RESULTS: There were 36 patients, 42 patients, 63 patients and 71 patients in each of the groups, respectively. The incidence of 30-day and 6-month MACE was numerically lowest among patients who received DES after atheroablation, although the differences did not reach statistical significance (30-day MACE: 0% DES with atheroablation, 4.8% BMS with atheroablation, 3.2% DES without atheroablation, 8.5% BMS without atheroablation; 6-month MACE: 2.8% DES with atheroablation, 19.0% BMS with atheroablation, 6.4% DES without atheroablation, 16.9% BMS without atheroablation). After adjustment, the use of atheroablation was not a predictor of MACE. CONCLUSIONS: This study suggests that in situations where directional atherectomy, rotational atherectomy or laser angioplasty is required to optimize stenting, the use of DES can minimize MACE associated with atheroablation.

Aged↗

PubMed1993

[Factors which affect the completion of the static register in primary care clinical notes].

OBJECTIVE: We set out to analyse factors which might affect the completion of the "static" register in the Primary Care clinical notes. DESIGN: Crossover and observation study with a control of the confusion in data analysis. SETTING: Albaycín Health Centre (Granada). PATIENTS AND OTHER PARTICIPANTS: A random sample of 428 sets of Primary Care clinical notes. MEASUREMENTS AND MAIN RESULTS: The "static" register showed over 50% observance in the sections on case history, allergies, tobacco and alcohol; whereas in housing (42%) and diet and physical activity (25%), the observance diminished until reaching its lowest level in counter-indicated medicines, anti-tetanus vaccination, a vaccine biography and family notes (< 10%). Age and gender variables showed virtually no association with the completion of the register. The static register was significantly better for husbands/wives as against children, for patients included in health programmes, for those included in adult rather than other types of programme, for those with smaller-sized families, for patients who used the Centre more and also for three of the doctors as against a fourth. Finally we constructed an overall indicator of the static register (OISR) which was submitted to a process of internal validation and was object of a multiple linear regression model which explained 51.3% of the variability. CONCLUSIONS: We underline the need to go deeper into those factors affecting the register as a first step towards understanding its completion. In this way we will find criteria for improving it or modifying the organisation of its observance and/or format. We discussed a method of overall indicators for tackling such a problematic.

Adolescent↗

PubMed2006

Exhaled-breath condensate pH can be safely and continuously monitored in mechanically ventilated patients.

BACKGROUND: Airway inflammation in acute and chronic respiratory diseases is characterized in part by abnormal pH in airway-lining fluid. The pH of exhaled-breath condensate (EBC) is low (acidic) in various pulmonary inflammatory diseases, including asthma, chronic obstructive pulmonary disease, cystic fibrosis, pneumonia, and acute respiratory distress syndrome. Because the time course of pH changes in the airway is not yet clear, we aimed to develop a method for frequent and intensive EBC pH data collection in mechanically ventilated patients. METHODS: We examined the collection, gas-standardizing (CO2 removal), and continuous monitoring of pH of EBC from the expiratory port of a Servo-i ventilator with mechanically ventilated patients. We developed a condensing device that attaches to the exhaust port and is chilled by an electric cooling system. We built a 2-chamber gas-standardization and pH-measuring device that attaches to the condensing system and records pH every 6 s. After safety testing, we enrolled mechanically ventilated patients (with diverse reasons for requiring ventilatory support) for up to 96 h of continuous EBC pH condensimetry. RESULTS: The pressure, volume, and flow of the ventilator attached to a test lung were unchanged by application of the condensimeter, at various flows (2-120 L/min) and ventilator settings. We monitored 19 pediatric patients for 6-96 h. The pH of the accumulated EBC in the storage container correlated with the geometric mean of all the pH data points from the condensimeter during the recording period (r2 = -0.95, p < 0.001), which internally validated that the condensimetry system provides accurate, well gas-standardized readings for up to 96 h. The EBC pH values were similar to published reports of single samples. The EBC pH became more acidic during clinical deterioration and normalized with recovery. CONCLUSION: Continuous monitoring of EBC pH from the ventilator exhaust port is safely achievable and reliably provides data that may become useful in monitoring critically ill patients.

Adolescent↗

PubMed2006

The evaluation of bone mineral density based on nutritional status, age, and anthropometric parameters in elderly women.

OBJECTIVE: To examine the relationship between bone mineral density and nutritional status, age, and anthropometrical data in elderly women. MATERIALS AND METHODS: A validated international nutrition-risk-screening questionnaire, the Mini Nutritional Assessment, was used for evaluation of nutrition. The Mini Nutritional Assessment is a clinical tool consisting of four items: anthropometric assessment, global evaluation, dietetic assessment, and subjective assessment. Height and body weight were measured while the participants wore indoor clothes and no shoes; mid-arm and calf circumferences were measured with tape measure. The measurements of skinfold thickness on triceps, waist, and thigh were taken with a caliper. Bone mineral density was measured at distal radius of the nondominant forearm by dual x-ray absorptiometry. RESULTS: Our results indicate that anthropometric parameters (height, weight, body mass index, skinfold thickness) in elderly women with osteoporosis were the smallest. It was determined that more fats and proteins are reserved in the body, the greater the bone mineral density is. The nutritional status and age had a significant influence on bone mineral density. It was determined that women with osteoporosis had a tendency for greater malnutrition risk according to Mini Nutritional Assessment. Women with osteoporosis had worse appetites and suffered from cardiovascular diseases more often. CONCLUSIONS: It was determined that the nutritional status of elderly women, assessed by the Mini Nutritional Assessment questionnaire, reflects bone mineral density. It was found that women's age and anthropometric data, reflecting fat reserves in the body (body mass index, skinfold thickness), are significantly related to low bone mineral density.

Absorptiometry, Photon↗

PubMed1991

[Incorrect technical terms in Hungarian dental terminology].

The standpoint of the Hungarian Scientific Academy in case of medical orthography is described. Attention is called that anatomic denominations have to be concordant with the currently valid international nomenclature. Improper technical terms frequently occurring in dental papers and parlance are pointed out and the correct denominations are expounded.

Dentistry↗

PubMedDate not supplied

[Development of a structured anxiety interview for seniors].

Since we face considerable practical problems in the assessment of elderly subjects with self-rating instruments (paper-pencil tests) measuring anxiety and, since we lack norms for the age of 65 and above, we developed a structured inventory (SAIS) for the assessment of anxiety in the elderly. The instrument comprises three components, anxiety normally is expressed in; all have been verified by empirical personality research: the cognitive, the physiological and the behavioural component. In a pilot study, we determined themes of anxiety relevant to elderly people. When the items were developed, we took into account aspects of the typical environment of the elderly and their comprehensive ability. In a reliability study 54 subjects (mean age: 72 years) were investigated. Item analyses showed low to average item difficulties and average selectivity. The split-half-reliability coefficient was rtt = .95; the internal consistency-coefficient was rtt = .91 (Kuder-Richardson). In a factor analysis five factors were extracted. They were interpreted as 'general' anxiety ("allgemeine Angstlichkeit"), as nervousness ("Neigung zu Nervosität"), fear of physical disability ("Furcht vor motorischer Behinderung"), personal insecurity ("persönliche Unsicherheit") and fear of helplessness ("Furcht vor Hilflosigkeit"). Finally, aspects of internal validity are discussed.

Aged↗

PubMed1990

[The value of recording the pulmonary insufficiency flow by continuous Doppler for the evaluation of systolic pulmonary artery pressure].

Systolic, diastolic and mean pulmonary artery pressures can be evaluated by Doppler recordings of the maximal velocity of tricuspid regurgitation and early and late diastolic pulmonary regurgitant flow. The aim of this study was to assess the reliability of the calculation of systolic pulmonary artery pressure from pulmonary regurgitant flow by comparing the values with those obtained from the tricuspid regurgitant flow in the same patient. With this objective in mind, we investigated 70 patients with an average age of 45 +/- 34 years, in sinus rhythm, all of whom had tricuspid and pulmonary regurgitant jets which could be recorded with continuous wave Doppler. Systolic pulmonary artery pressure was calculated as follows: from tricuspid regurgitation: maximum pressure gradient + 10 mmHg; from pulmonary regurgitation: 3 x early diastolic gradient - 2 x late diastolic gradient + 10 mmHg. The systolic pulmonary artery pressures calculated from tricuspid and pulmonary regurgitation were: 42 +/- 16 mmHg and 43 +/- 17 mmHg respectively (r = 0.97) with an estimated standard error of 4.7 mmHg. These results show that the recording of pulmonary regurgitation by continuous wave Doppler allows accurate estimation of pulmonary artery pressures. The calculation by the two methods using tricuspid and pulmonary regurgitant jets increases the reliability of the results and provides a means of internal validation of the Doppler technique.

Adolescent↗

PubMed1990

[Standardization of the immunochemical detection of apolipoprotein A-I and B].

Apolipoprotein A-I, the major protein of high-density lipoproteins, and apolipoprotein B, the major protein of low-density lipoproteins can serve as important predictor of the risk of cardiovascular diseases. The lack of an internationally valid standardization is a serious impediment to a broad application of the apolipoprotein measurements in the laboratory diagnosis of atherosclerosis. A common effort is at the present made by the IFCC Committee on Apolipoproteins together with several commercial organizations to achieve a consensus on a practical standardization procedure for the measurement of apolipoprotein A-I and B. The aim is a) to calibrate all commercially available Apo A-I and Apo B test kits using frozen serum pools previously standardized against primary reference materials and b) to select the secondary serum reference preparations which will substitute the frozen serum pools and will be used for the control of the validity of the own calibration. The available results from a preliminary exercise prove with a variation less than 5% for Apo A-I and less than 8% for Apo B with patients' samples that the use of common reference materials leads to the harmonization of the results obtained with different test systems for measurement of apolipoprotein A-I and B.

Apolipoprotein A-I↗

PubMed1990

A sensitive method for determination of cholesterol growth using model solutions of supersaturated bile.

We describe a novel, facile, and highly reproducible spectrophotometric technique to measure a cholesterol crystal growth curve. This method permits a quantitative estimate of the potency or comparative abundance of a given kinetic effector substance. In addition to several internal validation procedures, data are provided that support the usefulness of the technique in the assay of substances with either known promoting activity, i.e., human mucin glycoprotein, or those with known inhibitory activity, i.e., human apolipoprotein A-I.

Apolipoprotein A-I↗

PubMed1990

[Study of the quality of measurement by the Sickness Impact Profile. Assessment of the reliability of a method to determine the functional level of psychiatric patients].

The Sickness Impact Profile (SIP) is a questionnaire method of assessing the functional level within 12 fields which together provide a generalized measurement of the level of health in agreement with the definition of health by WHO. In the present investigation, the method was employed for the first time occasion for 58 suitable psychiatric patients and the result of Rasch's item-analysis of the replies to the individual questions showed altogether scales of good measurement quality. A single question, however, appeared to be unsuitable. The item-analysis is a demanding measurement for the internal validity and homogeneity and it supplements foreign investigations of the criteria-related validity of SIP.

Adolescent↗

PubMed1989

[Frequency of food consumption in children. Weekdays versus weekends].

The accurate assessment of nutritional quality or of food eating frequency in epidemiologic studies depends among other things on the internal validity of the method. The purpose of this study was to compare the mean food eating frequencies at meals and between-meals of 20 specific food items obtained from a two-weekday-diet record to those obtained from one weekend-day. A three-day-diet record including a weekend-day was completed by 549 eleven-year old children with the help of their parents. For each pair of food frequencies observed, a Student t test was performed. The results showed that when comparing the means for two weekdays to one weekend-day, significant differences (p less than 0.05) were observed for soft drinks, pastries, milk and vegetables. Also fruit juices, whole grain cereals, fresh fruits, milk, green and yellow vegetables were eaten significantly less at meals during the weekend-day. Between-meal eating is generally more salted or more sweetened during the weekend-day. Foods generally considered to be more nutritious are eaten less during the weekend-day. The differences in food frequencies obtained showed the need of including one weekend-day in a three-day-diet record to avoid the overestimation of food consumption and of the quality of the diet.

Beverages↗

PubMed1987

The effectiveness of tactile stimulation as a form of early intervention: a quantitative evaluation.

The results of studies examining the effectiveness of tactile stimulation as a form of sensory enrichment for infants and young children were analyzed by the use of recently developed quantitative methods that treat research synthesis as a unique type of scientific inquiry. Nineteen studies meeting certain predetermined criteria were included in the review. The 19 studies contain 103 statistical hypothesis tests that evaluated the effectiveness of tactile stimulation programs. Analysis of these tests, based on the calculation of effect sizes, revealed that subjects receiving some form of controlled tactile stimulation performed better on a variety of dependent measures than subjects not receiving intervention. Larger treatment effects were associated with pre-experimental designs, and also with studies in which the internal validity was rated as poor. Several other study characteristics, such as how the subjects were assigned to conditions and how the dependent measure was recorded, were related to study outcome as measured by effect size. The results indicate that an accurate interpretation of tactile stimulation studies cannot be made without consideration of specific design variables and study characteristics.

Child Development↗

PubMed1984

Scientific challenges in the application of randomized trials.

In recent years, scientific challenges in the application of randomized trials have become more apparent, especially with the extension of such trials to the assessment of nondrug treatments, such as health education, psychotherapy, and health care provision. Six issues (individual v group randomization, blinding and unblinding, the effect of trial participation on outcome, selective subject participation, treatment compliance, and standardized v individualized treatment) are discussed in terms of their impact on internal validity, generalizability (external validity), and clinical relevance. Specific design strategies may be necessary to enhance these methodological and clinical desiderata. Attention to these challenges should lead to improvements in future randomized trials.

Attitude↗

PubMedDate not supplied

A meta-analytic analysis of effects of psychoeducational interventions on length of postsurgical hospital stay.

Forty-nine studies of the relationships between brief psychoeducational interventions and the length of postsurgical hospitalization are reviewed using meta-analysis. Results show that interventions reduce hospital stay about 1 1/4 days and that reduction does not depend on whether the studies were published or not, whether the discharging physician was aware of the patient's experimental condition, or whether studies were lacking in internal validity. The interventions' effects on length of hospital stay are distinctly smaller in more recent studies, with analysis suggesting current treatments incorporate fewer components than earlier studies. Lesser effects are also found when the treatment is compared with a placebo-treatment group rather than a usual-care control group. This may be because placebo procedures often include educational and socially supportive components that constitute part of the psychoeducational interventions under review. The present study, providing a more stable foundation than previously available, supports the belief that brief psychoeducational interventions may be cost effective with surgical patients of many kinds because the length of hospital stay is reduced.

Cost Control↗

PubMed1984

Perspectives on borderline subtypes--overview of current research.

This paper has reviewed recent efforts to subtype patients within the borderline group. An overview of current definitions of the borderline syndrome was followed by a critical evaluation of recent empirical investigations designed to subtype within the larger domain of borderline pathology. Studies of borderline patients have, in large part, been based on the descriptive-phenomenological approach. It has been argued that while establishing a reliable diagnosis based on signs and symptoms provides internal validation for current theories of the borderline syndromes, studies providing external validating criteria are sorely needed.

Borderline Personality Disorder↗

PubMed1982

Carcinoma cervicis uteri. Long-term follow-up therapeutic results.

The principle of the therapy of carcinoma cervicis uteri in the Research Institute of Clinical and Experimental Oncology in Brno is the combination of betatron megavoltage irradiation and cobalt 60 irradiation with intracavital radium irradiation. On the basis of many years' study concerning the therapy and therapeutic results of this tumor accurate directions of total therapy were elaborated. Carcinoma is diagnosed and classified precisely according to valid international directions. In addition to basic examination, limb lymphography was introduced giving the strategy of irradiation when lymphatic system is involved and in early stages of the disease. By preliminary evaluation of the obtained data a certain improvement of therapeutic results is proven. About 15% more patients are alive till 5 years without any signs of the disease than in precedent years. In spite of a high dose summation given by the extent of megavoltage irradiation the number of postirradiation reaction, nor early late, is increased to much. Complex therapy of this tumor is performed by a team of physicians composed of gynecologist, radiologist, rentgendiagnosticist, pathologist, and radiation physicist. By increasing the number of cured patients and their return and enclosure into further working process the savings in state budget are achieved. The effectiveness of the carcinoma cervicis uteri therapy is therefore dependent not only on earlier diagnosis and modern irradiation technique, but also on the cooperation of a team of physicians who plan, perform and follow the therapy.

Carcinoma↗

PubMed1980

General purpose of research designs.

The purposes and criteria for formulating a design of research, conditions for judging causality, and use of research design as a control of variance are discussed. The purpose of a research design is to provide a plan of study that permits accurate assessment of cause and effect relationships between independent and dependent variables. The classic controlled experiment is an ideal example of good research design. Factors that jeopardize the evaluation of the effect of experimental treatment (internal validity) and the generalizations derived from it (external validity) are identified. Sources of variance can be controlled by eliminating a variable, randomization, matching, or including a variable as part of the design. A research project should be so designed that (1) it answers the questions being investigated, (2) extraneous factors are controlled, and (3) the degree of generalization that can be made is valid.

Analysis of Variance↗