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PubMed2003

[Profile of baccalaureate curriculum graduate students in 1997].

The purpose of this study is to describe the profile of the B.Cur. graduates who completed their studies in 1997 at the Rand Afrikaans University. Theoretical points of departures were used, such as Muller's career management description (Muller, 1998: 353-362) and Northeastern University's five-step model career services (Northeastern University, sa:1). After taking all the factors into consideration that play a role in career management, the researcher will be able to compile a complete profile of the B.Cur. graduates of 1997. It is important to the nursing education institution to know the profile of the graduates, in order to adapt the programme to the needs of the students. With a quantitative survey design, data was gathered telephonically, through a self-composed questionnaire. The structured questionnaire has content validity in terms of conceptualization. Of the thirty-one students, data was gathered on twenty-nine of them. Descriptive statistics were used to analyze the data. The profile of the graduates is described according to fourteen factors from the questionnaire.

Adult↗
PubMedDate not supplied

[Quantitative bone ultrasonography: state of the art and perspectives].

Quantitative Ultrasound (QUS) is a relatively new method of bone assessment that measures the velocity of sound and the broadband ultrasound attenuation at different skeletal sites: heel and phalanges. This is a mobile, inexpensive, easy to perform and radiation-free technique, capable of assessing not only bone density, commonly measured by means of Single Energy X-ray Absorptiometry, SXA, Dual Energy X-ray Absorptiometry, DXA and Quantitative Computed Tomography, QCT, but also its elasticity and structure. QUS has been validated for diagnosis of osteoporosis and prevention of hip fractures. Very recently, QUS was also been applied to the study of uremic osteodistrophy, of female premenopausal osteoporosis, male osteoporosis and in paediatric population. Moreover, many studies in the dialysis population has also shown the effectiveness of QUS at the phalanges site in evaluating bone turn-over and bone osteopenia. QUS may be an useful tool for the nephrologist in the day by day monitoring of uremic osteodistrophy and secondary hyperparathyroidism.

Bone Density↗
PubMed1992

["Indicators of Reha-Status (IRES)"--a patient questionnaire for assessing need and success of rehabilitation].

A basic instrument is presented which enables essential parameters of rehabilitation patients' somatic, functional and psychosocial status to be brought out and data collected at a "middle level of detail" in a standardized manner, i.e. a patient questionnaire which can be used to complement medical assessment or, for example in follow-up, as a stand-alone tool. Development and testing of the instrument has been supported over the past three years by the LVA Württemberg pension insurance fund, both financially and conceptually. In the present article, questionnaire contents and structure are described, and validation findings reported, standardization on a representative sample of the resident population (n = 1848) is set out. The validation studies performed showed the instrument to be reliable, valid and sensitive, and meeting with good acceptance on the part of patients. Finally, a specifically designed computer programme is set out which facilitates questionnaire data input and basic analyses. Potential applications for the IRES questionnaire are for example seen in describing rehabilitation course and outcome, in documenting the effectiveness of rehabilitation measures (quality control), or in the framework of rehabilitation diagnosis, in particular relative to functional and psychosocial dimensions.

Activities of Daily Living↗
PubMed2003

Psychoanalysis today.

The paper discusses the precarious position of psychoanalysis, a therapeutic approach which historically has defined itself by freedom from constraint and counted treatment length not in terms of number of sessions but in terms of years, in today's era of empirically validated treatments and brief structured interventions. The evidence that exists for the effectiveness of psychoanalysis as a treatment for psychological disorder is reviewed. The evidence base is significant and growing, but less than might meet criteria for an empirically based therapy. The author goes on to argue that the absence of evidence may be symptomatic of the epistemic difficulties that psychoanalysis faces in the context of 21st century psychiatry, and examines some of the philosophical problems faced by psychoanalysis as a model of the mind. Finally some changes necessary in order to ensure a future for psychoanalysis and psychoanalytic therapies within psychiatry are suggested.

Journal Article↗
PubMed1990

The developmental record: reliability and validity in a clinical population.

Currently, the Developmental Record is widely used with developmentally disabled adults, at least in the midwestern and southwestern region of the United States. Since it inception in 1974, there have been no subsequent reliability and validity studies confirming its clinical usefulness. For the present study a total of 1,069 Developmental Record protocols were obtained from archival files of a large midwestern facility for mentally retarded persons. Analyses revealed high internal reliabilities, but questionable validity. Specifically, the subscale structure of the instrument was not confirmed by the factor analysis.

Disability Evaluation↗
PubMed1989

Classifying cells from light microscopic bit features by binary logic. Application to grade neuronal injury in cerebral ischemia.

Degradative cellular processes within neurons were analyzed and graded by a conceptually new approach that decoupled the process of subcellular feature analysis and grading, the latter being based on the severity of observed deterioration in subcellular features. Rather than evaluate the cell's histologic image in a panoramic manner, investigators were required to give simple yes-no decisions about the presence or absence of a specific pathologic feature (bit feature as opposed to panoramic analysis). Multiple elementary decisions create a binary representation of the cell image that can be easily handled and analyzed using computer techniques to generate all possible unique phenotypes of the scanned neuronal population. In the first application of this method, however, the number of possible phenotypes were reduced by imposed a priori logic on the separation scheme focusing on a single cellular structure (the nucleus) that was followed through the stages of structural decay. We experimentally validated four neuronal types of five theoretical possibilities when three nuclear bit features were used in typing. Grading of neuronal injury for groups of normal, ischemic, and ischemic and reperfused rats into two, three, and four categories are reported. The consistency at which the method can be implemented was assessed by calculating the mean and standard deviation of the reconciled typing decisions given by the four investigators. The group of the four investigators showed less than 2, 3, and 5% error when grading cells from control, ischemic, and ischemic-reperfused animals, respectively.

Animals↗
PubMed1988

Hospital cost, resource use, and diagnostic related groups for gynecology patients.

The purpose of this study was to analyze hospital resource consumption by age for gynecology patients and to examine whether the assumptions made when the Diagnostic Related Groups payment was structured appear to be valid for our hospital. All gynecology admissions (N = 2232) at a large academic medical center during a 15-month period were analyzed by age using the Diagnostic Related Group format. Older patients generally consumed a disproportionately higher share of resources. Length of hospital stay, intensive care unit use, blood transfusion requirements, and overall hospital cost generally increased with age. Although mean Diagnostic Related Group reimbursement per patient also rose with age, it plateaued for patients 65 years of age and older. However, our hospital did not sustain a loss in providing care under Diagnostic Related Groups for older patients, except for the group of patients between the ages of 75-79 years. Although older gynecology patients generally had higher hospital resource consumption than younger patients, the current Diagnostic Related Group system seemed to adequately reimburse our hospital for their care.

Adolescent↗
PubMed1983

The Brief Symptom Inventory: an introductory report.

This is an introductory report for the Brief Symptom Inventory (BSI), a brief psychological self-report symptom scale. The BSI was developed from its longer parent instrument, the SCL-90-R, and psychometric evaluation reveals it to be an acceptable short alternative to the complete scale. Both test--retest and internal consistency reliabilities are shown to be very good for the primary symptom dimensions of the BSI, and its correlations with the comparable dimensions of the SCL-90-R are quite high. In terms of validation, high convergence between BSI scales and like dimensions of the MMPI provide good evidence of convergent validity, and factor analytic studies of the internal structure of the scale contribute evidence of construct validity. Several criterion-oriented validity studies have also been completed with this instrument.

Adult↗
PubMed1983

Direct and reversible inhibition of estradiol-stimulated prolactin synthesis by antiestrogens in vitro.

The antiestrogens tamoxifen and monohydroxytamoxifen inhibited the estradiol-stimulated increase in prolactin synthesis by dispersed cells in culture derived from immature rat pituitary glands. Monohydroxytamoxifen had a relative binding affinity for the estrogen receptor similar to that of estradiol, whereas tamoxifen's relative binding affinity was approximately 3%. This was consistent with the observation that monohydroxytamoxifen was 30 times more potent than tamoxifen as an antiestrogen in vitro. To avoid the possibility that tamoxifen was fractionally metabolized to monohydroxytamoxifen by the pituitary cells, the p-methyl, p-chloro, and p-fluoro derivatives of tamoxifen that are unlikely to be converted to monohydroxytamoxifen were tested for activity. The substitution did not have a detrimental effect on their ability to inhibit the binding of [3H]estradiol to either rat uterine or pituitary gland estrogen receptors. Similarly, the derivatives of tamoxifen inhibited estradiol-stimulated prolactin synthesis at concentrations that were consistent with their relative binding affinities. Although it is clearly an advantage for tamoxifen to be metabolized to the more potent antiestrogen monohydroxytamoxifen, we have shown that this is not a prerequisite for the antiestrogenic actions of tamoxifen. With the direct actions of antiestrogens established, the pituitary cell system was validated for further structure-activity relationship studies. Overall, the inhibition of estradiol-stimulated prolactin synthesis by antiestrogens is competitive and reversible with estradiol, an effect that can be explained by interactions with the estrogen receptor system.

Animals↗
PubMed1995

[The construction of a model for predicting adolescent smoking behavior from a 7-year follow-up survey].

Predictive factors for adolescent smoking behavior were examined prospectively in a cohort of 199 adolescents who participated in a survey in March 1983 and were followed up about 7 years later. In 1983, as junior high school students (grades 1-3), subjects completed a questionnaire which consisted of variables on smoking behaviors of subjects' family and friends, attitudes toward smoking, knowledge about the effects of smoking on health, and self-prediction of future smoking behavior. In 1990, a similar survey including variables on subjects' smoking behavior was again carried out. At that time, all were 20 years or older. It was found that the number of friends in 1983 who smoke was strongly associated with smoking behavior in 1983, and for both sexes smoking behavior in 1983 and self-prediction of future smoking behavior in 1983 were the factors which were associated with smoking behavior in 1990. Furthermore, a model for predicting smoking behavior was deduced from the foregoing results and the findings of prior studies. The covariance structure analysis supported the validity of the model and revealed that smoking behavior in 1983, number of friends who smoke, and self-prediction of future smoking behavior were important in predicting smoking behavior 7 years later.

Adolescent↗
PubMedDate not supplied

[The value of life. Development of an assessment system for therapeutic strategies].

The wide therapeutic supply which a present is available for diverse disorders, together with a excess of indiscriminate scientific information, occasionally complicates the possibility of acquiring a wide experience in the treatment of certain patients (limited experience). To acquire genuinely useful experience, it is necessary to accumulate simiular experiences from our environment, with it being necessary to precisely define, in an objective manner, concepts which until now are difficult to quantify (risk of mortality or morbidity, survival, quality of life, etc.). The definition of these parameters, shall favor the creation of homogenous groups (isoseverity indices), which is the first step in the evaluation of more complex conceps, such as; quality of life, increase of life expectancy, quality adjusted life years (QALY's), and beneficial application, all of which validated in diverse hospital media. Based on the previous, we would obtain other calculated parameters; the benefit (of the patient), the use (of the procedure), and the efficacy (of the physician or the unit). Once these parameters have been standarized, it shall be possible to compare them with the results published in other media, considered to be standards, with the aim of establishing the corresponding self-evaluation. The evaluation of the cost of each process, is a compulsory procedure, to produce, if possible, based on the previous results, a better distribution of the means without a decrease in the quality of assistance. With the aim of evaluating the results in an objective and quantifiable manner, we have worked these last years on developing assessment applied to the evaluation of predictive and isoseverity indices, such as the cost/benefit evaluation in critical, geriatric, and oncological patients, and in those with artificial nutrition in the home. The fruit of this labor has come together in the production of a computerized information system (SAETA), which builds de previously validated modules into is structure, thus permiting the storage and subsequent multifactoral analysis of the results.

Decision Theory↗
PubMed1996

Establishing a therapeutic milieu with adolescents.

Adolescents with acute psychiatric illness need an environment that emphasizes containment, structure, support, involvement and validation. Within such an environment therapeutic relations based on collaboration can be developed. However, these relations require nursing actions that facilitate adolescents' acceptance of containment, their ability to form attachments and development of achievement. The proposed collaborative approach for nursing care positions the adolescent as an active participant in the treatment process. The collaborative approach encourages a sense of responsibility for self and enhances the adolescent's skills to cope with situations and relations that pose difficulties through the development of self-awareness and problem-solving abilities.

Adolescent↗
PubMed1997

Regression calibration in failure time regression.

In this paper we study a regression calibration method for failure time regression analysis when data on some covariates are missing or mismeasured. The method estimates the missing data based on the data structure estimated from a validation data set, a random subsample of the study cohort in which covariates are always observed. Ordinary Cox (1972; Journal of the Royal Statistical Society, Series B 34, 187-220) regression is then applied to estimate the regression coefficients, using the observed covariates in the validation data set and the estimated covariates in the nonvalidation data set. The method can be easily implemented. We present the asymptotic theory of the proposed estimator. Finite sample performance is examined and compared with an estimated partial likelihood estimator and other related methods via simulation studies, where the proposed method performs well even though it is technically inconsistent. Finally, we illustrate the method with a mouse leukemia data set.

Animals↗
PubMed1998

[Perceived quality of life of elderly somatic nursing-home patients. Construction of a measuring instrument].

An instrument to assess perceived quality of life of physically frail elderly persons is needed in nursing home research. Four existing instruments (Pain, Somatic Autonomy, Life Satisfaction, Social Isolation) and two new scales (Perceived Safety, Perceived Autonomy) were tested for internal consistency, validity of the dimensional structure, discriminatory power, and feasibility. The scales were administered to 243 physically frail elderly nursing home patients. Three of the existing scales were shown to have sufficient internal consistency (KR-20 > .70), and the two new scales were moderately consistent (KR-20 > .50). The expected dimensions were confirmed in general by principal component analysis of the items. Significant group differences were detected by means of scale means. The mean administration time was 20 minutes. It is concluded that feasible instrument has been developed that can be applied in future research in nursing homes.

Activities of Daily Living↗
PubMed1998

Evaluating pathophysiologic processes rather than clinical end points in improving therapeutic practice.

Cardiovascular clinical trials and clinical practice are currently aimed at reducing morbidity and mortality, but a more efficient and effective guide to therapeutic efficacy would be surrogate markers that track the progression of disease that precipitates clinical end points. Structural alterations of the left ventricle and abnormalities of endothelial function that lead to functional and structural alterations of the vasculature are the best candidates for useful surrogate markers. Methods for quantitating these functional and structural alterations must be validated to provide documentation of their sensitivity and specificity.

Cardiovascular Diseases↗
PubMed1987

Assessing pathological detoxification fear among methadone maintenance patients: the DFSS.

This study assessed the reliability, validity, discriminative accuracy, and factor structure of the Detoxification Fear Survey Schedule (DFSS). Prevalence of detoxification fear and its correlates also were assessed. Random samples from three geographically, culturally, and racially disparate populations (N = 271) of treated opioid addicts were used. The DFSS had a test-retest r = .935 and demonstrated several indicants of validity. A briefer version (DFSS-14) showed superior psychometric properties and could identify correctly 81% of the detox fear subjects while it excluded 55% of nonfear subjects. The DFSS-14 had a replicated three-factor structure that accounted for 62.1% of total item variance in the validation sample. Factor two, probably best named dose reduction fear, was replicated in all populations. A cut-off score set at the nonfear mean is recommended for clinical use. A brief clinical interview of positive scorers quickly should eliminate false positives and, thus, efficiently identify most of those with detoxification fear.

Adult↗
PubMed1998

GENFOLD: a genetic algorithm for folding protein structures using NMR restraints.

We report the development and validation of the program GENFOLD, a genetic algorithm that calculates protein structures using restraints obtained from NMR, such as distances derived from nuclear Overhauser effects, and dihedral angles derived from coupling constants. The program has been tested on three proteins: the POU domain (a small three-helix DNA-binding protein), bovine pancreatic trypsin inhibitor (BPTI), and the starch-binding domain from Aspergillus niger glucoamylase I, a 108-residue beta-sheet protein. Structures were calculated for each protein using published NMR restraints. In addition, structures were calculated for BPTI using artificial restraints generated from a high-resolution crystal structure. In all cases the fittest calculated structures were close to the target structure, and could be refined to structures indistinguishable from the target structures by means of a low-temperature simulated annealing refinement. The effectiveness of the program is similar to that of distance geometry and simulated annealing methods, and it is capable of using a very wide range of restraints as input. It can thus be readily extended to the calculation of structures of large proteins, for which few NOE restraints may be available.

Algorithms↗
PubMed1998

Some useful statistical methods for model validation.

Although formal hypothesis tests provide a convenient framework for displaying the statistical results of empirical comparisons, standard tests should not be used without consideration of underlying measurement error structure. As part of the validation process, predictions of individual blood lead concentrations from models with site-specific input parameters are often compared with blood lead concentrations measured in field studies that also report lead concentrations in environmental media (soil, dust, water, paint) as surrogates for exposure. Measurements of these environmental media are subject to several sources of variability, including temporal and spatial sampling, sample preparation and chemical analysis, and data entry or recording. Adjustments for measurement error must be made before statistical tests can be used to empirically compare environmental data with model predictions. This report illustrates the effect of measurement error correction using a real dataset of child blood lead concentrations for an undisclosed midwestern community. We illustrate both the apparent failure of some standard regression tests and the success of adjustment of such tests for measurement error using the SIMEX (simulation-extrapolation) procedure. This procedure adds simulated measurement error to model predictions and then subtracts the total measurement error, analogous to the method of standard additions used by analytical chemists.

Animals↗