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At least 739 records · Page 41Linked to original sources
PubMed2004

Improving estimation of the prognosis of childhood psychopathology; combination of DSM-III-R/DISC diagnoses and CBCL scores.

OBJECTIVE: To compare the predictive validity of the clinical-diagnostic and the empirical-quantitative approach to assessment of childhood psychopathology, and to investigate the usefulness of combining both approaches. METHOD: A referred sample (N = 96), aged 6 to 12 years at initial assessment, was followed up across--on average--a period of 3.2 years. It was assessed to what extent DISC/DSM-III-R diagnoses--representing the clinical-diagnostic approach, and CBCL scores--representing the empirical-quantitative approach, predicted the following signs of poor outcome: outpatient/inpatient treatment, or parents' wish for professional help for the child at follow-up, disciplinary problems in school, and police/judicial contacts. RESULTS: Both diagnostic systems added significantly to the prediction of poor outcome, and neither of the two systems was superior. Use of both systems simultaneously provided the most accurate estimation of the prognosis, reflected by the occurrence of future poor outcome. Even diagnostic concepts that are generally regarded as relatively similar, such as ADHD (DSM) and attention problems (CBCL), or conduct disorder (DSM) and delinquent behavior (CBCL), appeared to differ in their ability to predict poor outcome. CONCLUSIONS: The present study supports the use of the empirical-quantitative approach and the clinical-diagnostic approach simultaneously, both in research and in clinical settings, to obtain a comprehensive view of the prognosis of psychopathology in children.

Adolescent↗
PubMed1990

The empirical foundations of psychoanalytic approaches to psychological testing.

The view that psychoanalytic approaches to psychological testing lack empirical foundations is disputed by systematically examining the ways in which psychoanalytic theory expands the sources of data available to the psychological tester at each step in the assessment process. The contention is made that it is unscientific to restrict the concept of what constitutes scientific rigor to formal experimentation with statistical analysis.

Humans↗
PubMed2000

Amiodarone: maximising survival benefit with empiric or guided therapy.

Review of available data suggests that serial drug testing in patients with a history of sustained ventricular tachyarrhythmias using various antiarrhythmic drugs including amiodarone is able to identify subgroups with favorable and unfavorable outcome (patient groups with suppression vs. no suppression of inducibility of VT/VF). These results more likely reflect patient selection rather than drug effects, thus limiting the role of electrophysiologically guided antiarrhythmic therapy to actively modify outcome. All major and actual antiarrhythmic drug trials including an amiodarone arm, have chosen to deliver this drug empirically in both patients with asymptomatic as well as severely symptomatic life-threatening sustained ventricular tachyarrhythmias instead of a guided approach. The empiric approach is therefore adequate until new valid data comparing the empiric with the guidedor the invasive with the non invasiveapproach tell us otherwise.

Amiodarone↗
PubMed2003

Modeling habitat suitability for moose in coastal northern Sweden: empirical vs process-oriented approaches.

Habitat models may provide viable tools for co-management of large ungulates and forest resources, yet their applicability has not been comprehensively evaluated in managed forest. We examined 2 inherently different approaches to model the relative winter habitat suitability for moose (Alces alces) in the coastal area of northern Sweden. An empirical approach based on GPS positions of 15 female moose was used to scrutinize the assumptions and functional mechanisms of a process-oriented, conceptual approach, based on published material on the species' preferences for habitat components related to food and cover. For both model approaches habitat was described using estimates of forest-stand characteristics based on satellite imagery. The empirical model also included variables relating to topographic properties of the landscape as well as distances to landscape features. The output from both models was a habitat suitability index (HSI) score, enabling the models to be compared with each other. The models showed different results, highlighting the need to include the spatially explicit distribution of environmental variables in future conceptual, process-oriented models.

Animals↗
PubMed2000

An examination of the robustness of the empirical Bayes and other approaches for testing main and interaction effects in repeated measures designs.

In a previous paper, Boik presented an empirical Bayes (EB) approach to the analysis of repeated measurements. The EB approach is a blend of the conventional univariate and multivariate approaches. Specifically, in the EB approach, the underlying covariance matrix is estimated by a weighted sum of the univariate and multivariate estimators. In addition to demonstrating that his approach controls test size and frequently is more powerful than either the epsilon-adjusted univariate or multivariate approaches, Boik showed how conventional multivariate software can be used to conduct EB analyses. Our investigation examined the Type I error properties of the EB approach when its derivational assumptions were not satisfied as well as when other factors known to affect the conventional tests of significance were varied. For comparative purposes we also investigated procedures presented by Huynh and by Keselman, Carriere, and Lix, procedures designed for non-spherical data and covariance heterogeneity, as well as an adjusted univariate and multivariate test statistic. Our results indicate that when the response variable is normally distributed and group sizes are equal, the EB approach was robust to violations of its derivational assumptions and therefore is recommended due to the power findings reported by Boik. However, we also found that both the EB approach and the adjusted univariate and multivariate procedures were prone to depressed or elevated rates of Type I error when data were non-normally distributed and covariance matrices and group sizes were either positively or negatively paired with one another. On the other hand, the Huynh and Keselman et al. procedures were generally robust to these same pairings of covariance matrices and group sizes.

Bayes Theorem↗
PubMed2005

A Bayesian model comparison approach to inferring positive selection.

A popular approach to detecting positive selection is to estimate the parameters of a probabilistic model of codon evolution and perform inference based on its maximum likelihood parameter values. This approach has been evaluated intensively in a number of simulation studies and found to be robust when the available data set is large. However, uncertainties in the estimated parameter values can lead to errors in the inference, especially when the data set is small or there is insufficient divergence between the sequences. We introduce a Bayesian model comparison approach to infer whether the sequence as a whole contains sites at which the rate of nonsynonymous substitution is greater than the rate of synonymous substitution. We incorporated this probabilistic model comparison into a Bayesian approach to site-specific inference of positive selection. Using simulated sequences, we compared this approach to the commonly used empirical Bayes approach and investigated the effect of tree length on the performance of both methods. We found that the Bayesian approach outperforms the empirical Bayes method when the amount of sequence divergence is small and is less prone to false-positive inference when the sequences are saturated, while the results are indistinguishable for intermediate levels of sequence divergence.

Bayes Theorem↗
PubMed1997

Empirical treatment of febrile neutropenia: evolution of current therapeutic approaches.

Administration of empirical antibiotic therapy is now standard practice in the management of febrile neutropenia, but there has been considerable debate about the selection of an efficacious empirical antimicrobial regimen over the past 2 decades. A variety of approaches, including both monotherapeutic and multidrug regimens, have been demonstrated to be effective, although no one regimen has been proven to be superior to another. Changes in the epidemiology of infectious organisms and the growing emergence of highly drug-resistant strains make it necessary to continually reevaluate the therapeutic options. Fortunately, the number of therapeutic options has also been broadening as new antimicrobial agents, including third-generation cephalosporins and carbapenem antibiotics such as imipenem and meropenem, become available. Optimal management is directed by the findings of a clinical evaluation of the patient as well as an awareness of institutional patterns of infection and susceptibility of likely infecting organisms.

Anti-Bacterial Agents↗
PubMed1995

Estimation of precision in DLW studies using the two-point methodology.

Previous attempts to estimate precision of doubly labeled water (DLW) estimates of CO2 production, using propagation of error analyses, have necessarily made simplifying assumptions which may compromise the resultant error estimate. Using an empirical iteration approach, error distributions for the DLW calculation were generated which overcome these problems. The error distribution for CO2 estimates generated by DLW is symmetrical but not normal. The distribution is significantly truncated such that the 99% inclusion limits are 2.034 SD and not 2.58 SD. The precision error (99% CI for mean as percent of the mean) in DLW experiments, when using duplicate analyses, varies between approximately 3% and 47% depending on the ratio of the elimination constants of the two labels (ko/kd), experimental duration and initial isotope dose. The error could be improved by approximately 10 fold by increasing the number of replicates at all six isotope determinations from 2 to 5. Estimating precision in actual experiments can be made using the same empirical approach. The resultant estimates can be of extreme value in evaluating the role of precision as a factor influencing deviations during validation studies, and also for weighting mean estimates in applications of the technique. The deviations of DLW estimates from those made simultaneously by indirect calorimetry in a small mammal validation study were generally greater than the precision of the DLW estimates of CO2 production. This may indicate there are more problems with the technique than precision alone.

Animals↗
PubMed2002

Treatment of the extraintestinal manifestations of inflammatory bowel disease.

There is a paucity of randomized, controlled therapy studies of the extraintestinal manifestations of inflammatory bowel disease (IBD). Most current therapeutic approaches are empiric or based on approaches to therapy in other settings. In the past year anecdotal evidence has emerged for the use of therapies that neutralize tumor necrosis factor-a in both ankylosing spondylitis and the dermatologic extraintestinal manifestations. Topical tacrolimus has also emerged as a potentially useful therapy for dermatologic manifestations. Finally, patients with IBD occasionally become transplant recipients. One study reported worsening IBD after orthotopic liver transplantation for primary sclerosing cholangitis, and another reported the benefit of renal transplantation in amyloidosis-induced renal failure.

Antibodies, Monoclonal↗
PubMed1979

A clinical-interactive approach to alcoholism treatment evaluation.

This presentation is concerned with a particular approach to empirical evaluation of psychologically-oriented alcoholism treatment which offers hope for results that are more relevant to clinical applications than has been the case with past empirical research. This particular approach has been termed, for want of a better term, a "clinical-interactive" one for two reasons. First, the psychological makeup of alcoholic patients and the experiential nature of the treatment process they undergo constitute much of the focus of investigation, providing more vivid conceptual bridges to clinical applications. Second, treatment is conceived of as a result of the interaction between the nature of the patient and the patient's experienced involvement in various aspects of the treatment process and openness to continued treatment involvement, rather than as categorically different formal treatment procedures. In what follows, the utility of this approach will be illustrated with respect to the sort of prediction models applicable to alcoholism treatment as explored in a pilot study.

Alcoholism↗
PubMed2004

Does empirical research make bioethics more relevant? "The embedded researcher" as a methodological approach.

What is the status of empirical contributions to bioethics, especially to clinical bioethics? Where is the empirical approach discussed in bioethics related to the ongoing debate about principlism versus casuistry? Can we consider an integrative model of research in medical ethics and which empirical methodology could then be valuable, the quantitative or the qualitative? These issues will be addressed in the first, theoretical part of the paper. The concept of the "embedded researcher" presented in this article was stimulated by the two questions, (1) how can we safeguard that our research will yield valid and meaningful results to practice? and (2), how can we convince clinical colleagues that medical ethics offers relevant contributions to the analysis and solution of problems? One tentative answer has been our effort to elaborate a coherent methodological research approach in the field of end-of-life issues integrating qualitative and quantitative as well as casuistic methodologies. This development is characterized in the second part describing the ECOPE Study (short title) "Ethical Conditions Of Passive Euthanasia." The achievements and limitations of the suggested approach of the "embedded researcher" are discussed referring to 3 examples of our joint studies about ethical issues concerning (1) critical decision-making in neonatology (2) limitation of treatment in intensive care (3) problems with doctor-patient conversation at the end-of life in oncology. Conclusions from our studies are put to discussion in the final part of the paper about how to further develop research in the field of end-of-life care and, maybe, clinical bioethics as a whole.

Bioethical Issues↗
PubMed2001

Community-acquired pneumonia. Diagnostic and therapeutic approach.

Optimal empiric therapy of CAP is with appropriate monotherapy (e.g., doxycycline, levofloxacin). Combination therapy is problematic because of potential side effects and high cost. Empiric coverage should have a high degree of activity against both typical and atypical pathogens. The antibiotic selected should have an excellent side-effect profile and be relatively inexpensive. Clinicians should be selective in their choice of antibiotic for CAP and choose an antimicrobial that has little or no resistance potential, is relatively inexpensive, and permits i.v.-to-PO switch monotherapy.

Anti-Bacterial Agents↗
PubMed1989

[Methodologic evaluation of the relation of blood pressure and skinfold thickness: an epidemiologic approach].

The empirical evidence concerning the relationship between blood pressure and anthropometric characteristics (triceps skinfold, adiposity, and arm circumference) was assessed by means of meta-analysis. Different studies were evaluated critically for strength of design, methods and associations. It was found that the association between blood pressure and triceps skinfold holds for three different demographic categories. The question as to the independence of these associations remained unsolved. The effect of arm adiposity on the measurement of blood pressure was also discussed. Recommendations are give in order to standardize blood pressure measurements in clinical and research settings.

Adolescent↗
PubMed1983

Narcolepsy: an initial clinical approach.

Pragmatic, empirical methods are available for the diagnosis and treatment of narcolepsy. Diagnosis can be based on the history of specific symptoms; a questionnaire scale can reliably confirm sleepiness, while performance tests and other laboratory procedures may illuminate the clinical picture when the diagnosis is unclear. A treatment program includes scheduling of sleep and naps, careful progressive refinement of the drug regimen, dependable record keeping, and supportive or insight-oriented psychotherapy aimed at enhancing adherence to prescribed regimens.

Adult↗
PubMed2006

Empirical mode decomposition and synchrogram approach to cardiorespiratory synchronization.

We use the empirical mode decomposition method to decompose experimental respiratory signals into a set of intrinsic mode functions (IMFs), and consider one of these IMFs as a respiratory rhythm. We then use the Hilbert spectral analysis to calculate the instantaneous phase of the IMF. Heartbeat data are finally incorporated to construct the cardiorespiratory synchrogram, which is a visual tool for inspecting synchronization. We perform analysis on 20 data sets collected by the Harvard medical school from ten young (21-34 years old) and ten elderly (68-81 years old) rigorously screened healthy subjects. Our results support the existence of cardiorespiratory synchronization. We also investigate the origin of the cardiorespiratory synchronization by addressing the problem of correlations between regularities of respiratory and cardiac signals. Our analysis shows that regularity of respiratory signals plays a dominant role in the cardiorespiratory synchronization.

Adult↗
PubMed1993

A multidisciplinary approach to pediatric pain: an empirical analysis.

A comprehensive assessment and multidimensional approach are critical for optimal outcomes in pediatric pain management. The purpose of this article is to describe the structure, function, and results of a multidisciplinary pain team composed of individuals from nursing, pediatric medicine, and pharmacology. The team's activities, including individual consultation on a school age/adolescent unit, are described.

Adolescent↗
PubMed1998

Linkage disequilibrium and gene mapping: an empirical least-squares approach.

This paper proposes a novel approach for fine-scale mapping of disease genes that is based on the well-known linkage-disequilibrium parameter delta. Using a very simple, very general model, I show how delta can be interpreted in terms of identity-by-descent probabilities. The value of delta follows a piecewise curve along the chromosome, with the maximum occurring at the disease locus where the two pieces intersect. A semiparametric, multilocus approach is used to fit this nonlinear regression curve in order to estimate the gene location. Using the bootstrap to empirically estimate much of the probability model from the data avoids the need for many detailed population assumptions. One advantage of the approach is its use of the observed covariance structure of the data, which can be highly informative as to the gene location. I illustrate the method on the cystic fibrosis data of Kerem et al.

Chromosome Mapping↗
PubMed2003

Prediction of cancer incidence in the Nordic countries: empirical comparison of different approaches.

Prediction of the future number of cancer cases is of great interest to society. The classical approach is to use the age-period-cohort model for making cancer incidence predictions. We made an empirical comparison of different versions of this model, using data from cancer registries in the Nordic countries for the period 1958-1997. We have applied 15 different methods to 20 sites for each sex in Denmark, Finland, Norway and Sweden. Median absolute value of the relative difference between observed and predicted numbers of cases for these 160 combinations of site, sex and country was calculated. The medians varied between 10.4 per cent and 15.3 per cent in predictions 10 years ahead, and between 15.1 per cent and 32.0 per cent for 20 year predictions. We have four main conclusions: (i) projecting current trends worked better than assuming that future rates are equal to present rates; (ii) the method based on the multiplicative APC model often overestimated the number of cancer cases due to its exponential growth over time, but using a power function to level off this growth improved the predictions; (iii) projecting only half of the trend after the first 10 years also gave better long-term predictions; (iv) methods that emphasize trends in the last decade seem to perform better than those that include earlier time trends.

Cohort Studies↗