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At least 865 records · Page 48Linked to original sources
PubMed2000

Clinical risk associated with appointment noncompliance in heart transplant recipients.

This study examined the prevalence of appointment noncompliance in 101 heart transplant recipients and how appointment noncompliance is related to patient profile and clinical risk. Appointment noncompliance was defined as patients not showing up at 1 or more planned clinic appointments (at a minimal frequency of every 3 months) during the previous year. Clinical variables were collected from medical files. Psychosocial variables were measured using established instruments. Medication noncompliance was assessed using electronic event monitoring. Paired t test, Wilcoxon 2-sample test, chi-square test, or Fisher exact test were used for statistical analysis as appropriate. The prevalence of appointment noncompliance was 7%. Appointment noncompliers were significantly younger, were less likely to live in a stable relationship with a partner, were more depressed, perceived their health as poorer, experienced more symptom distress, and had significantly more drug holidays. Fifty-seven percent of the appointment noncompliers experienced 1 or more late acute rejection episodes, compared to 2% of the appointment compliers. Appointment noncompliance is a critical behavioral risk factor in the occurrence of late acute rejection episodes in heart transplant patients. Patient profiles allow the identification of patients at risk for appointment noncompliance.

Adult↗
PubMed1978

Measurement of cellular DNA mass by flow microfluorometry with use of a biological internal standard.

Use of a biological standard (chicken erythrocytes) mixed with experimental cell populations allows control of all variables in flow microfluorometric determination of DNA content. These variables include both staining and instrument procedures. In addition, the use of a biological standard allows determination of cellular DNA mass in unperturbed cell populations. DNA mass measured by FMF technique correlates closely with values reported in the literature that used biochemical techniques.

DNA↗
PubMed2003

[Evaluative research on occupational rehabilitation: the effectiveness of a health care service subject to dismantlement].

This article deals with the results obtained from 1995 to 1997 by an innovative occupational rehabilitation model for individuals with repetitive strain injury/work related musculoskeletal disorder (RSI/WRMD), developed by the Campinas Occupational Rehabilitation Center under the Brazilian National Institute for Social Security. The study had two objectives: 1) to reconstruct the program as a precondition for evaluation and 2) to evaluate the model's effectiveness in reestablishing the autonomy of individuals with RSI/WRMD. The methodology involved document analysis in order to reconstruct the program's background in terms of problem identification, organizational participation, awareness-raising, staff characteristics and responsibilities, and profile of the clientele. An analysis of 221 patient files provided the basis for constructing an evaluative instrument consisting of different dimensions, variables, and indicators, which was applied to a sample of 47 patient histories prior and subsequent to rehabilitative intervention. High effectiveness was observed in the model, with variations in the different target dimensions.

Adult↗
PubMedDate not supplied

[Social inequality in health and the utilization of health services among the elderly in Latin America].

OBJECTIVE: To learn if there is social inequality in health and in the utilization of health services among the elderly in six cities of Latin America: Buenos Aires, Argentina; São Paulo, Brazil; Santiago, Chile; Havana, Cuba; Mexico City, Mexico; and Montevideo, Uruguay. METHODS: This study used data from a project called Health, Well-being, and Aging in Latin America and the Caribbean (known as the "SABE project"). To investigate the presence of social inequality in health an ordinal probit model was used, with health status indicated by the following dependent variables: activities of daily living, instrumental activities of daily living, physical mobility, and self-rated health. To measure social inequality in the utilization of health services two characteristics were assessed: one for outpatient medical services (whether or not individuals received outpatient care, and how many times), and one for hospital admissions (whether or not individuals were hospitalized). For outpatient services, we estimated a negative binomial hurdle model, and for hospital admissions, a logit model was constructed. RESULTS: Our main results suggest the presence of social inequality in health in all the cities, with better-off socioeconomic groups having better health. The difference in health was less marked in Havana, Buenos Aires, and Montevideo, and it was more pronounced in São Paulo and Mexico City. With respect to the utilization of health services we found inequalities in the use of outpatient services in Santiago, Mexico City, and São Paulo. In Santiago and Mexico City, more schooling was associated with a higher number of expected outpatient medical visits; however, the opposite was found in São Paulo. For hospital admissions, inequality was found only in São Paulo, with individuals with more years of schooling being much more likely to be hospitalized. CONCLUSION: To a certain extent, our results reflect the socioeconomic and demographic characteristics of the countries in which each of the six cities is located. The cities in the countries with the worst social indicators (high income inequality and low human development index) tended to have the greatest inequalities in health and in the utilization of health services.

Age Factors↗
PubMed1997

Comparison of manual and automated probing in an untreated periodontitis population.

Diagnosis of periodontal disease progression involves recording two probing attachment level measurements over an adequate time interval. A diagnostic instrument which exhibits less measurement variability allows for increased sensitivity and earlier disease detection. Traditionally, a manual probe with an occlusal stent of the cementoenamel junction (CEJ) as a reference landmark has been the method of choice. Automated probes that use an occlusal disk as the reference landmark have been developed as an alternative means of measure. The aim of this study was to compare the variability of these two probing methods. Four hundred eleven (411) interproximal sites in 46 untreated periodontitis patients were monitored by a single examiner over a 6-month period. Each site was measured on a monthly basis, first with an automated probe (AP) followed by a manual probe (MP) in combination with a custom-fabricated acrylic stent. Measurement variability of the two probing methods was also compared over a 7-day interval. The AP measurements were significantly more variable than the MP measurements (P < 0.001) when considering the variability between two passes at the same visit. Over the 6-month period, the MP measurements demonstrated significantly more variability than the AP measurements (P < 0.001). It was also noted that MP measurements exhibited more variability at sites with frequent bleeding during the 6 months of the study (P = 0.006). The results of this study demonstrate that AP may have less variability of attachment level measurements over a 6-month period and may be less influenced by local inflammatory changes. However, future comparison studies should include multiple examiners to reduce examiner bias and should alternate the probing method to reduce bias created by local tissue changes from multiple probings.

Adult↗
PubMed1977

Isothermal gas chromatographic method for the rapid determination of carbamazepine ("tegretol") as its TMS derivative.

A rapid, simple isothermal gas chromatographic (GC) method for the quantitation of carbamazepine ("Tegretol") in serum as its trimethylsilyl derivative has been developed. A single chloroform extraction using 1.0 ml of serum, a 10-min derivatization step, and analysis on a 3% OV-1 (methyl silicone) GC column gives a linear response to a carbamazepine concentration up to 25 mg/liter. A non-drug internal standard (tetracosane) compensates for variables in extraction, injection, and instrumental changes occurring during analysis. This method was found to be free of interferences from endogenous substances in the serum, as well as from toxic concentrations of commonly used drugs. Day-to-day precision at concentration levels of 2, 5, and 10 mg/liter ranged from 2.9 to 4.4% (CV). Standard addition studies of carbamazepine added to serum resulted in a mean recovery of 95%. To ensure accurate results, all standards were prepared in serum.

Carbamazepine↗
PubMed1986

The impact of expectations on faculty job satisfaction.

Although job satisfaction of nurses within the clinical area has been heavily studied, the satisfaction of nurse faculty members has seldom been examined. This study looks at the relationship of the role of the department chairperson to the satisfaction of faculty. The sample was composed of 163 faculty in eight state supported baccalaureate/masters programs. Age, length of service, size of the department, and the size of the program served as control variables. Two self-designed instruments (CPQ-E and CPQ-P) based on Need Fulfillment Theory created an Expectation Discrepancy Score for each faculty member. Job satisfaction was measured by the JDI. The relationship between the Expectation Discrepancy Score and job satisfaction was found to be significant (Fg = 15.786, p less than 05). Several recommendations were suggested.

Adult↗
PubMed2000

Current perspectives The diagnosis of acute pulmonary embolism. A review of the literature and current clinical practice.

The optimal approach to the diagnosis of acute pulmonary embolism is still controversial. The poor sensitivity and specificity of most of the clinical manifestations, the suboptimal accuracy of the majority of the laboratory and instrumental examinations and the highly variable local availability of the diagnostic resources, makes it in fact difficult for a univocal strategy to be adopted. Recently published practical guidelines, however, support the use of lung scanning (either ventilation/perfusion or only perfusion) as a first-line imaging test, since this approach allows for a correct diagnosis in most patients, after careful history taking, physical examination and electrocardiogram, chest X-ray and arterial blood gas analysis performance. When lung scanning is non-diagnostic, either serial non-invasive (i.e. ultrasonographic) evaluation of the lower limbs or pulmonary angiography should follow. Growing evidence is accumulating on the use of spiral computed tomography scanning either as an alternative or as a complement to lung scanning, while echocardiography should be reserved for the bedside evaluation of critically ill patients, when more validated techniques are not readily available. The role of plasma D-dimer measurement has yet to be defined, especially in hospitalized patients. In current clinical practice, however, these recommendations seem to be only partially followed. Depending in fact on the different characteristics of the populations examined in the seven available studies reporting on this issue, the use of the different diagnostic techniques appears highly variable. Although a standard diagnostic pathway does not seem applicable to all patients with suspected acute pulmonary embolism, further work is nonetheless needed in order to identify in different patient subsets the diagnostic approach capable of minimizing the use of diagnostic resources while obtaining the greatest amount of information.

Acute Disease↗
PubMed2001

Assessing the surveillance capability of Canada's national health surveys.

We assessed Canada's national health surveys as surveillance instruments, with emphasis on comparing the temporal structure of data sets with those generated by the US Behavioral Risk Factor Surveillance System (BRFSS). Only the Canadian Tobacco Use Monitoring Survey (CTUMS) has the BRFSS capability to generate continuous, uniform time series with monthly intervals. These time series can offer substantial extra value for retrospective analysis such as program evaluation in addition to surveillance. Expanding CTUMS is a simple option for providing an ongoing, uniform monthly survey instrument for non-tobacco variables. The Canadian Community Health Survey (CCHS) will generate monthly data, and could potentially generate useful continuous time series even though surveys at the health region and provincial levels will alternate annually. Reconfiguring the CCHS, or even implementing a provincial surveillance survey based on the BRFSS model are other viable options, but each option has associated tradeoffs or obstacles.

Canada↗
PubMed2001

Preventable adverse patient outcomes: a closed claims analysis of respiratory incidents.

Closed claims analysis of adverse anesthesia outcomes was initiated through the AANA Foundation in 1995 to examine adverse outcomes of anesthesia care provided by Certified Registered Nurse Anesthetists (CRNAs). A research team of 8 CRNAs using an instrument incorporating more than 150 variables undertook document analyses of closed claim files. All files reviewed involved incidents in which the CRNA named in the policy was potentially involved in the adverse patient outcome. Thirty-eight percent (58/151) of CRNA-related claims involved a respiratory incident as the primary cause of the negative patient outcome. Patient outcomes involving respiratory incidents were more likely to result in death or permanent injury compared with nonrespiratory incidents (P < .01). Reviewers found that respiratory claims were more likely to have involved inappropriate anesthesia management (P < .01), more likely to have involved a lack of vigilance (P < .01), and more likely to have been judged by the reviewer as preventable (P < .01). A higher percentage of respiratory incidents occurred in emergency cases (75% vs 34%, P < .01) and in cases involving general anesthesia (44% vs 17%, P < .01). Adverse respiratory incidents are largely preventable and frequently result in serious patient morbidity and mortality.

Anesthesia↗
PubMed1999

[Neonatal nursing: undergraduate nursing students' knowledge].

The present study was carried out at the Municipalities of São Paulo and Guarulhos with undergraduate nursing students and aimed at evaluating their knowledge regarding neonatal nursing and, if necessary, to contribute to the program reformulation. Thus, we would be able to improve nurses knowledge on the full-term new born care. In order to develop a structured questionnaire to be used as an instrument to measure the studied variable, aspects of the theoretical content related to the most common care procedures at the neonatal unit were selected. Authors found that students' theoretical knowledge on the theme was regular.

Clinical Competence↗
PubMed2002

[Occupational stress and health in a sample of chilean executives].

BACKGROUND: Most individual and organizational costs related to job stress are due to preventable health problems. To study the impact of occupational stress in Chile, an instrument that evaluates the different variables involved in the stress process is required. AIM: To study the effects of work stressors and psychological variables on health among Chileans managers. To study reliability and validity of the Spanish version of the Occupational Stress Indicator (OSI-2). SUBJECTS AND METHODS: A translated version of the OSI-2 was applied to a sample of 264 white-collar managers. RESULTS: A high frequency of symptoms was reported by our sample. Back pain was the most frequently reported symptom in managers with high levels of stress. Regression analysis showed that, together, work stressors and psychological characteristics significantly explained self-perceived mental (27.6%) and physical (22.9%) health variance. Responsibilities of the executive role were the stressors most highly associated with poor stress outcomes. The psychological variables most strongly correlated with mental and physical health were Problem-focused Coping and the subscale Impatience of Type A Behavior. The reliability and validity of the OSI-2, Spanish version, were reasonably high. CONCLUSIONS: The transactional model of work stress was confirmed in a sample of Chilean managers evaluated with the Spanish version of the OSI-2.

Administrative Personnel↗
PubMedDate not supplied

[Assessment of occupational noise exposure: methodology, measurement error, evaluation criteria].

BACKGROUND: Occupational noise exposure can be monitored directly by personal sampling or indirectly, by area sampling. Personal sampling is performed using an integrating sound level meter, worn by the worker while performing his/her job. When area sampling is used, measurements need to be made in all locations where a typical worker stays while performing his/her tasks; the respective partial lengths of exposure need to be accurately monitored, and the time-weighted average sound level of the measured noise levels must be calculated. OBJECTIVES: Current regulations identify three different thresholds, corresponding to different types of action, but they do not propose any standard criteria to decide whether a threshold has been exceeded. Defining standard procedures to assess occupational noise exposure and identifying such thresholds is crucial. METHODS: Using empirical data collected in the field, the effects are illustrated of the number of sampling locations and of the partial lengths of exposure on area sampling measurements, and the effects of duration of noise exposure on both area and personal samplings. RESULTS: When dealing with area samplings, an accurate definition of both sampling locations and partial lengths of exposure is crucial. When arbitrary decisions are taken in selecting sampling locations and/or establishing partial lengths of exposure, spatial changes in noise level and operator' displacements while performing his/her tasks may affect results. Sampling for less than the duration of noise exposure is the major contributor to measurement error, particularly under conditions of unpredictable variation in noise level. In fact, as noise level in the non-monitored time fraction is unknown, measurement error cannot be determined. We estimate that, even under the most favorable circumstances, sampling should last not less than 40% of the duration of a given noise-generating occurrence, for repeated measurements to be dispersed within a range not wider than that generated by the instrumental error. Inter-daily variability is another important aspect in personal noise exposure evaluation. This is a general occurrence, whose effects cannot be controlled by simply considering weekly instead of daily exposures. Results of an investigation, covering about 60 different jobs within a primary aluminum plant, show an inter-daily variability in noise exposure greater than 5 dBA in about 75% of cases. CONCLUSIONS: Personal sampling, when correctly performed and covering the total duration of exposure, provides the most reliable result as it integrates noise over all locations where the worker actually stays while performing his/her tasks, and over the total length of time spent in each task. We propose extending personal sampling to the total duration of actual noise exposure as the standard procedure for monitoring daily personal noise exposure, and valid for the majority of work places. When the range of daily noise exposure includes one regulatory threshold, corresponding to a given type of action, we propose as a standard decision criterion to refer prudentially to the upper 95% confidence limit of the LEP,d arithmetic mean. Such criterion would allow to standardize procedures and decision methods, with the prospect of further improvements in the assessment of exposure to noise.

Humans↗
PubMed1992

The injury experience of the competitive athlete with a disability: prevention implications.

The purpose of this project was to describe the injury experiences of athletes with disabilities. A cross-disability instrument was developed to measure variables of interest. A retrospective survey was administered to 426 athletes who participated at the 1989 national competition of the National Wheelchair Athletic Association (NWAA), United States Association for Blind Athletes (USABA), and the United States Cerebral Palsy Athletic Association (USCPAA). The definition of injury was any trauma to the participant that occurred during any practice, training, or competition session that caused the athlete to stop, limit, or modify participation for 1 d or more. Thirty-two percent (N = 137) of the total respondents reported at least one time-loss injury. By organization, 26% of the total injuries were from the NWAA and 37% were from the USABA and USCPAA, respectively. The shoulder and arm/elbow accounted for 57% of the total NWAA injuries. Fifty-three percent of the injuries to the USABA athlete were to the lower extremity. Injuries to the USCPAA athlete were distributed among four body locations, knee (21%), shoulder (16%), forearm/wrist (16%), and leg/ankle (15%). The athlete with a disability demonstrated approximately the same percentage of injury as the athlete without a disability in similar sport activities. Biomechanical considerations of locomotion and specific sport skills should be analyzed by experts to reduce the percentage of injuries.

Adult↗
PubMed2006

IT support for clinical pathways--lessons learned.

Clinical pathways are an effective instrument to decrease undesired practice variability and improve clinician performance. IT applications embedded into clinical routine work can help to increase pathway compliance. Successfully implementing such applications requires both a responsive IT infrastructure and a participatory and iterative design process aimed at achieving user acceptance and usability. Experiences from the implementation and iterative improvement of an online surgical pathway at Marburg University Medical Centre have shown that pathway conformance actually could be improved by the use of IT. An analysis of the iterative design process has shown that future pathway projects can benefit from the lessons learned during this project. Based on these lessons a method for developing well adapted interaction mechanisms is presented, which is aimed at improving process alignment. Our goal is to build up a library of tested reusable components to reduce the number of iterations for pathway implementation.

Academic Medical Centers↗
PubMedDate not supplied

[Depression and self concept of patients with acute viral hepatitis].

As part of a complex multimodal study of the biological, psychological and social situation of patients with acute viral hepatitis, the specific hypothesis that patients with this disease appear to be especially depressive is examined. Two instruments were used to assess variables of depression: the Giessen-Test, a standardized personality questionnaire (Beckmann, Brähler, Richter, 1983) and the idiographic role-repertorygrid (Kelly 1955). Seeing that self-esteem and basic affective state of the hepatitis patients as a whole differed significantly from that of patients with depression, it does not seem justifiable to speak of "the depressive" hepatitis patient. On the contrary, differential investigation discriminates three subgroups of patients with depressed, "normal" and hypomanic mood states. Since the measures of depression used here are quite stable and thus rather "trait" than "state" variables and further, some patients even appear to be hypomanic, the observed depression is not, as discussed in the literature, regarded to be "psychoreactive".

Acute Disease↗
PubMed1983

B-scan texture classification: a study using physical and theoretical models.

Recent clinical trials, in our own centre and elsewhere, have demonstrated the ability of A- and B-scan texture analysis techniques to provide useful in vivo separation of certain disease conditions. The present paper reports studies, using physical and theoretical models of tissues, aimed at identifying the particular sets of textural features which are most effective in achieving such separations. Using a 3.5 MHz, single element manual scanner, a total of 300 B-scans have been collected from four physical models consisting of gel-embedded 'point' scatterers, with differing mean separations. Additionally, computer modelling has been used to obtain a further 500 B-scans from 14 statistically different scattering situations. The total set of B-scans thus obtained has been subjected to a variety of texture classification procedures which have previously been developed for application in other imaging fields, such as cytology and aerial photography. The results are discussed in terms of: i) the features which are best suited to the classification of B-scans, and ii) the manner in which the resulting classification schemes are sensitive to variables of the ultrasonic scanning instrumentation.

Biometry↗
PubMed1993

Acute myeloid leukemias expressing lymphoid-associated antigens: diagnostic incidence and prognostic significance.

A portion of patients with acute myeloid leukemia also display surface antigens associated with lymphoid development (Ly+AML). The incidence of Ly+AML varies considerably between independent studies, both overall and with regard to individual antigens. On average, lymphoid-associated antigen expression is relatively low in AML. The reasons for some striking differences between conflicting reports are not clear, but are most probably due to various technical aspects including several arbitrary parameters. The data accumulated from the literature lead to the following conclusions: (i) use of different reagents against the CD surface antigens, different positive/negative cut-off levels, analysis of fresh or frozen cell material and variable sensitivities of the analytical instruments (expression of lymphoid-associated antigens was commonly weaker than myeloid-associated markers) seriously influence the results; (ii) most antigens (CD1, CD2, CD3, CD5, CD8, CD10, CD19, CD20, CD21, CD22) were expressed on less than 10% of AML cases; (iii) the CD4 and CD7 antigens, also found on normal monocytic and immature myeloid progenitor cells, were detected in 24% and 15% of AML cases, and their expression correlated with FAB M4/M5 and M1/M2 morphology, respectively; (iv) differences between pediatric and adult Ly+AML were restricted to CD4 and CD19 expression being detected more often in childhood cases; (v) there is no cytogenetic anomaly specific for Ly+AML; anomalies exclusively associated with lymphoid malignancies were not seen; aberrations involving 11q23, 14q32, and the 9;22 translocation seem to be increased; (vi) in most studies, expression of lymphoid-associated antigens (with the exception of CD7) on AML blasts lacked prognostic significance; CD7+AML appears to be a particular subset of malignant myeloid progenitors. In summary, these findings suggest that in general, Ly+AML may not represent a biologically distinct form of leukemia as these cases have similar clinical features and respond to therapy in a comparable manner.

Adult↗