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At least 1,153 records · Page 64Linked to original sources
PubMed2000

Adherence to treatment in children with epilepsy: who follows "doctor's orders"?

PURPOSE: The goal of the present study was to examine sociocultural, medical, family environment, and individual cognitive factors that predict adherence to treatment in children with epilepsy. METHODS: The study subjects (4-13 years old) were enrolled in a longitudinal seizure study at the first visit to the seizure clinic, attended at least 6 months, and had at least two appointments. Baseline predictors, which were obtained by interview, chart review, and psychometric testing, included sociocultural and family environment, seizure and previous treatment history, child behavior, cognitive functioning (IQ), and family stress. Four latent factors tapping these indicators of risk (acculturative risk, seizure severity, behavior problems, family environment) and two measured variables (IQ and life events) were hypothesized. Outcomes were visit adherence (proportion of scheduled appointments kept, plus proportion without unscheduled contacts), medication report (proportion of visits at which parent report of medication agreed with records), and medication levels (proportion of serum anticonvulsant levels within expected range for dosage). Two-step analytic procedure included confirmatory factor analysis to validate the hypothetical structure of the baseline risk indicators, followed by structural equation modeling to examine longitudinal relations between baseline risk and subsequent adherence outcomes. RESULTS: Significant prospective relationships included acculturative risk associated positively with visit adherence and medication levels, behavior problems associated negatively with visit adherence and medication levels, family environment associated negatively with medication report, life events associated positively with medication levels and visit adherence, and cognitive functioning (IQ) associated positively with medication levels. Seizure severity was not associated significantly with any adherence outcome. There also were no significant within-time associations between adherence outcomes. CONCLUSIONS: Contrary to clinical expectations, families at higher acculturative risk and with higher life events reported greater adherence. Seizure severity did not influence adherence. The three adherence measures were statistically independent of each other.

Acculturation↗
PubMed1996

Application of decision theory to DUI assessment.

The application of decision theory to screening of driving under the influence (DUI) offenders is illustrated in an evaluation study that investigated the validity of a structured interview and a survey instrument. These findings are examined graphically using the relative operating characteristic (ROC). This graph relates the proportion of true-positive cases to the proportion of false-positive cases for various placements of the decision cut-off score. The ROC's two principal parameters, test sensitivity and examiner bias, are used to provide a complete quantitative description of the performance of two screening instruments. A major goal of this study is to show how a new measure of examiner bias, the "cost ratio," improves the evaluation of DUI screening programs.

Accidents, Traffic↗
PubMed2006

Increased risk of migraine in Marfan's syndrome?

OBJECTIVE: To study the prevalence of migraine in Marfan's syndrome. MATERIAL AND METHODS: Patients were recruited from Landsforeningen (a patient organization) for Marfan's syndrome. A total of 46 persons were eligible for a validated semi-structured telephone interview by a physician trained in headache diagnostics. RESULTS: The prevalence of migraine without aura was 13% among men and 40% among women. The prevalence of migraine with aura was 44% among men and 37% among women. The overall prevalence of migraine was 63% with an equal sex ratio. This corresponds to a 3.6- and 2.0-fold significant increased risk among men and women, respectively, compared with the general population. CONCLUSION: The high prevalence and equal sex ratio of migraine is puzzling and likely to be secondary to Marfan's syndrome. It might be associated with dural ectasia, as the prevalence of dural ectasia is similar to that of migraine in Marfan's syndrome.

Adolescent↗
PubMed2002

Contextual assessment of couples therapy: the Clinical Discourse Q-Sets.

This article describes a method for creating highly contextual assessments of couples therapy interaction using concepts from Systemic Functional Linguistics (SFL). According to SFL, talk in interaction serves three primary functions: to mediate social relations, to negotiate representations of reality, and to organize and structure the event as coherent. These concepts are operationalized using observational q-methodology. The Clinical Discourse Q-Sets (CDQS) include three separate q-sets for use by trained observers in rating 12-min segments of couples therapy conversation. Each q-set captures one aspect of the communication process as defined by Systemic Functional theory. Good-to-high reliabilities for the q-set profiles over various (n = 16) couples therapy episodes were found. Preliminary evidence for the conceptual structure and clinical validity of the system was found.

Adult↗
PubMed1989

Meta-analyses of the reliability of Type A behaviour measures.

The accuracy of assessments of Type A behaviour made using different methods is the focus of active debate. Presented here are preliminary meta-analyses regarding: (a) internal consistency, test-retest and parallel forms reliabilities of the most frequently used questionnaire (Jenkins Activity Survey); (b) inter-rater and test-retest reliabilities of the most prospectively valid method (Friedman Structured Interview); and (c) correlations and percentage classification agreement between these measures. The findings generally suggest highly statistically significant yet moderate effect strengths for these various psychometric properties.

Coronary Disease↗
PubMed2005

Simulated bioprosthetic heart valve deformation under quasi-static loading.

For more than 40 years, the replacement of diseased natural heart valves with prosthetic devices has dramatically extended the quality and length of the lives of millions of patients worldwide. However, bioprosthetic heart valves (BHV) continue to fail due to structural failure resulting from poor tissue durability and faulty design. Clearly, an in-depth understanding of the biomechanical behavior of BHV at both the tissue and functional prosthesis levels is essential to improving BHV design and to reduce rates of failure. In this study, we simulated quasi-static BHV leaflet deformation under 40, 80, and 120 mm Hg quasi-static transvalvular pressures. A Fung-elastic material model was used that incorporated material parameters and axes derived from actual leaflet biaxial tests and measured leaflet collagen fiber structure. Rigorous experimental validation of predicted leaflet strain field was used to validate the model results. An overall maximum discrepancy of 2.36% strain between the finite element (FE) results and experiment measurements was obtained, indicating good agreement between computed and measured major principal strains. Parametric studies utilizing the material parameter set from one leaflet for all three leaflets resulted in substantial variations in leaflet stress and strain distributions. This result suggests that utilization of actual leaflet material properties is essential for accurate BHV FE simulations. The present study also underscores the need for rigorous experimentation and accurate constitutive models in simulating BHV function and design.

Animals↗
PubMed2005

Determination of drug glucuronidation and UDP-glucuronosyltransferase selectivity using a 96-well radiometric assay.

A rapid and sensitive radiometric assay for UDP-glucuronosyltransferase (UGT) is described. UGT substrates are incubated in 96-well plates with microsomes in the presence of [14C]UDP-glucuronic acid, and 14C-labeled glucuronidation products are separated from the unreacted nucleotide sugar by solid-phase extraction using 96-well extraction plates. The assay was validated with 15 structurally diverse UGT substrates containing acidic, phenolic, and hydroxyl reacting groups. Glucuronidation velocities for these compounds were determined using human, rat, and dog liver microsomes, and reaction kinetics were studied with 1-naphthol and 4-methylumbelliferone. Results obtained with the new assay confirmed the previously reported rank order of glucuronidation velocity of several typical UGT substrates and the finding that the glucuronidation of most of these compounds is significantly faster in dog than in human liver microsomes. UGT specificity of five compounds was determined using recombinant human UGTs. The major UGT isoforms identified were UGT1A6, UGT1A7, and UGT1A9 for 4-methylumbelliferone; UGT1A6 and UGT1A8 for 1-naphthol; UGT2B7 for naloxone; UGT1A3 and UGT2B7 for ketoprofen; and UGT1A4 for trifluoperazine. Identical results were obtained with a conventional high-performance liquid chromatography method coupled to mass spectrometric detection. The new assay should prove valuable for rapidly benchmarking recombinant UGTs and microsomal preparations from different species and tissues, identifying high-turnover compounds during drug discovery, and reaction phenotyping studies.

Animals↗
PubMedDate not supplied

The granularity of medical narratives and its effect on the speed and completeness of information retrieval.

OBJECTIVE: Using electronic rather than paper-based record systems improves clinicians' information retrieval from patient narratives. However, few studies address how data should be organized for this purpose. Information retrieval from clinical narratives containing free text involves two steps: searching for a labeled segment and reading its content. The authors hypothesized that physicians can retrieve information better when clinical narratives are divided into many small, labeled segments ("high granularity"). DESIGN: The study tested the ability of 24 internists and 12 residents at a teaching hospital to retrieve information from an electronic medical record--in terms of speed and completeness--when using different granularities of clinical narratives. Participants solved, without time pressure, predefined problems concerning three voluminous, inpatient case records. To mitigate confounding factors, participants were randomly allocated to a sequence that was balanced by patient case and learning effect. RESULTS: Compared with retrieval from undivided notes, information retrieval from problem-partitioned notes was 22 percent faster (statistically significant), whereas retrieval from notes divided into organ systems was only 11 percent faster (not statistically significant). Subdividing segments beyond organ systems was 13 percent slower (statistically significant) than not subdividing. Granularity of medical narratives affected the speed but not the completeness of information retrieval. CONCLUSION: Dividing voluminous free-text clinical narratives into labeled segments makes patient-related information retrieval easier. However, too much subdivision slows retrieval. Study results suggest that a coarser granularity is required for optimal information retrieval than for structured data entry. Validation of these conclusions in real-life clinical practice is recommended.

Cross-Over Studies↗
PubMed2004

Internal consistency and validity of a new physical workload questionnaire.

AIMS: To examine the dimensionality, internal consistency, and construct validity of a new physical workload questionnaire in employees with musculoskeletal complaints. METHODS: Factor analysis was applied to the responses in three study populations with musculoskeletal disorders (n = 406, 300, and 557) on 26 items related to physical workload. The internal consistency of the resulting subscales was examined. It was hypothesised that physical workload would vary among different occupational groups. The occupations of all subjects were classified into four groups on the basis of expected workload (heavy physical load; long lasting postures and repetitive movements; both; no physical load). Construct validity of the subscales created was tested by comparing the subscale scores among these occupational groups. RESULTS: The pattern of the factor loadings of items was almost identical for the three study populations. Two interpretable factors were found: items related to heavy physical workload loaded highly on the first factor, and items related to static postures or repetitive work loaded highly on the second factor. The first constructed subscale "heavy physical work" had a Cronbach's alpha of 0.92 to 0.93 and the second subscale "long lasting postures and repetitive movements", of 0.86 to 0.87. Six of eight hypotheses regarding the construct validity of the subscales were confirmed. CONCLUSIONS: The results support the internal structure, internal consistency, and validity of the new physical workload questionnaire. Testing this questionnaire in non-symptomatic employees and comparing its performance with objective assessments of physical workload are important next steps in the validation process.

Adult↗
PubMed1995

Psychiatric and medical features of near fatal asthma.

BACKGROUND: The associations between psychiatric caseness, denial, and self reported measures of handicap and morbidity due to asthma in patients suffering a near fatal attack of asthma have not been fully explored. METHODS: Seventy seven consecutive subjects who presented to Adelaide teaching hospitals with a near fatal attack of asthma were assessed with a validated semi-structured interview following discharge from hospital. RESULTS: 43% of the patients scored > or = 5 on the GHQ-28 questionnaire. There was a positive correlation between GHQ-28 score and limitation to daily activities due to asthma, and between GHQ-28 score and days lost from work, school or usual daily activities, both of which were retained after adjusting for age and sex. Asthma severity did not show a clear association with GHQ-28 score. The asthmatic patients reported high levels of denial, 57% scoring more than 3 out of 5 on the denial scale of the Illness Behaviour Questionnaire. Presentation with a history of progressive respiratory distress was negatively associated with denial score. This persisted after adjustment for age and sex--that is, those with high denial scores were more likely to report presentation as sudden collapse than progressive respiratory distress. CONCLUSIONS: Psychiatric caseness (GHQ score > or = 5) is associated with high levels of morbidity in asthmatic patients who survive a near fatal attack of asthma. High levels of denial in asthmatic subjects may be life threatening. The link between morbidity associated with asthma and psychiatric features, along with other psychosocial issues, warrants further investigation. A broader paradigm than the traditional medical model should be considered when assessing patients with asthma.

Adult↗
PubMed1992

The Elston-Stewart algorithm for continuous genotypes and environmental factors.

The Elston-Stewart algorithm for a normally distributed trait under a polygenic model is explained in detail and extended to allow for other continuous environmental variables. This formulation is especially useful for large pedigrees, as it avoids the need to invert matrices. Whereas it may not be feasible by this method to estimate all the various components of previously suggested models for polygenic inheritance, it can allow for a reasonably flexible pedigree correlational structure under which valid tests can be performed for fixed effects that may affect the phenotype.

Algorithms↗
PubMedDate not supplied

Validation of in vitro and in vivo methods for assessing endocrine disrupting chemicals.

The concepts that require validation in terms of the subject of endocrine disruption are listed and discussed. The main mechanisms by which endocrine disruption can occur are identified, and the assays required for the detection of adverse endocrine disruption toxicities associated with these mechanisms are discussed. The process of assay validation is considered. The validation of structure-activity relationships, the need for reference chemicals, and the problems recently encountered when attempting to reproduce endocrine disruption data are also explored. The most important conclusions derived from this analysis are that given the immature state of research into endocrine disruption toxicity, testing strategies and the types of assay employed should be kept under constant review; inevitably researchers need to accept the fact that future revision of each assay will be required. Second, given the current absence of any chemical that is universally accepted to be devoid of endocrine toxicity, assay specificity will be difficult to assess, and that imposes the need for alternative objective criteria for assessing the value of individual assays.

Animals↗
PubMed1998

Critical analysis of the pharmaceutical care research literature.

OBJECTIVE: To describe and evaluate published pharmaceutical care research and make recommendations to improve the quality of the literature. DATA SOURCES: MEDLINE and International Pharmaceutical Abstracts using the key word "pharmaceutical care," limited to research articles published January 1988-December 1996. STUDY SELECTION: Articles that evaluated the provision of pharmaceutical care in a defined population. DATA EXTRACTION: Citations (title and abstract) identified were reviewed. Articles potentially meeting the inclusion criteria were screened and scored according to the Pharmaceutical Care Research Checklist for the presence of criteria including pharmaceutical care process, methodology, and measures/outcomes. RESULTS: A total of 979 citations were identified. Of 57 abstracts identified as potentially meeting the inclusion criteria, 43 articles were eliminated, 2 were rejected, and 12 were accepted for analysis. Deficiencies identified included: a lack of research in community practice (n = 2), randomized controlled trials (n = 3), workload measurement (n = 6), and patient satisfaction (n = 1). Scoring according to the Pharmaceutical Care Research Checklist also identified the following deficiencies (maximum Composite Criterion Score [CCS] of 24): description of population sample (CCS 17), dropouts (CCS 13), informed consent (CCS 8), pharmacist training/qualifications (CCS 9), instrument validity (CCS 10), structure criteria (CCS 4), patient outcomes (CCS 11), and economic outcomes (CCS 12). The mean total checklist score was 37 of 50 (range 31-46). CONCLUSIONS: Few research studies have evaluated the provision of pharmaceutical care in a defined population. Deficiencies identified by low CCSs demonstrated the need for quality research design and a clear description of the pharmaceutical care process to evaluate the impact of pharmaceutical care. Recommendations for improvement in research design were made.

Humans↗
PubMed2002

Development of Body Modification and Excessive Exercise Scales for adolescents.

The present study was designed to develop a Body Modification Scale (BMS) to measure body change among adolescents and to modify an Excessive Exercise Scale (EES) into a shorter form for adolescents. Two hundred and twenty-one girls and 192 boys from Grades 7 to 10 completed the BMS and the EES. Factor analysis revealed three identical factors for the BMS for girls and boys: weight loss, weight gain, and muscle mass. Two identical factors for girls and boys were also revealed for the EES. Both factor structures were further validated on a separate sample of 286 adolescents (140 girls, 146 boys). The BMS and EES demonstrated excellent reliability (alpha > .86) and high test-retest reliability (alpha > .82) over 1 month. Good concurrent validity was also found for the weight loss factor of the BMS. These findings demonstrate the utility of these two scales for use with adolescents.

Adolescent↗
PubMed1991

Hormonal responsiveness by immature rabbit uterine epithelial cells polarized in vitro.

This paper reports the development of an in vitro cell culture system of polarized uterine epithelial (UE) cells from the immature rabbit. UE cells from immature rabbit were cultured on EHS (Engelbreth-Holm-Swarm) matrix-coated semipermeable filter inserts in a serum-free, phenol red-free defined medium. The cells in primary culture attached, proliferated, formed monolayers, and exhibited structural and functional polarity. Structural differentiation was validated by ultrastructural features, such as apical microvilli, intercellular junctions, desmosomes, and polar organization of apical vs. basal membrane domains. Trans-monolayer epithelial resistance, a reflection of functional tight junctions, preferential basal uptake of [35S]methionine, polarized distribution of labeled secretory proteins, and increased secretory activity marked by preferential apical secretion (greater than 90%) of proteins were indices of functional polarity. With the development and maintenance of polarized state by the UE cells, some of the newly synthesized proteins were sorted and vectorially secreted into their distinct compartments. De novo synthesis and exclusive apical secretion of uteroglobin (a progesterone-induced protein in vivo) by the polarized UE cells occurred in response to progesterone treatment in vitro. The hormone responsiveness was maintained for a prolonged period under these conditions. A culture system in which the UE cells maintain functional and morphological polarity and sustain their hormonal responsiveness facilitates the study of regulation of specialized functions by the UE cells that are regulated by steroid hormones and their interactions with the other uterine cell types.

Animals↗
PubMed2003

Measuring sense of coherence with only three items: a useful tool for population surveys.

OBJECTIVES: Sense of Coherence is the core construct of Antonovsky's salutogenetic model. To measure Sense of Coherence, a 29-item-questionnaire (SOC-29), a shortened 13-item version, and a simplified measure of only three items (SOC-3) are available. In our study, the last was tested in terms of the psychometric properties and compared with an alternative short form derived from the SOC-29. METHODS: Data with respect to the original SOC-29-scale, the SOC-3, and additional other health measures were collected in a representative general population survey, the German study 'Transitions in Alcohol Consumption and Smoking' (TACOS). Analyses of the factor structures, reliability and validity correlations are reported. RESULTS: The reliability and validity results of the SOC-3 were not encouraging. Subsequent item analyses revealed that three items taken out of the SOC-29 outperformed the SOC-3 in measuring Sense of Coherence in a simplified way. This newly developed instrument is presented as the Brief Assessment of Sense of Coherence (BASOC). CONCLUSION: The BASOC is a superior short form compared with the SOC-3 and is recommended for large surveys with limited space for questions.

Adaptation, Psychological↗
PubMed2006

The 20-item Toronto Alexithymia Scale: validation of factor solutions using confirmatory factor analysis on physiotherapy out-patients.

OBJECTIVE: Whilst the 20-item Toronto Alexithymia Scale (TAS-20) was developed to measure three intercorrelated dimensions, there is some debate as to whether the scale is best served by a two- or three-factor construct. In particular, there is some doubt as to whether clinical data exhibit the third factor. This study uses data from a sample of physiotherapy (physical therapy) out-patients in the UK to validate the factorial structure of a set of models postulated in the literature, including the three-factor model hypothesized by Bagby et al. (1994). METHOD: Data were collected from a sample of physiotherapy out-patients (N=242). Specialist factor analysis software (LISREL 8.54) was used to perform confirmatory factor analyses on a range of models proposed in the literature. RESULTS: The analysis supports the three-factor model assumed by Bagby et al. (1994), as well as most of the two-factor models suggested in the literature. CONCLUSIONS: This new set of clinical data supports most of the two- and three-factor models postulated in the recent literature, including the three-factor model advocated by Bagby et al. (1994).

Affective Symptoms↗
PubMed2025

Anticancer drug response prediction integrating multi-omics pathway-based difference features and multiple deep learning techniques.

Individualized prediction of cancer drug sensitivity is of vital importance in precision medicine. While numerous predictive methodologies for cancer drug response have been proposed, the precise prediction of an individual patient's response to drug and a thorough understanding of differences in drug responses among individuals continue to pose significant challenges. This study introduced a deep learning model PASO, which integrated transformer encoder, multi-scale convolutional networks and attention mechanisms to predict the sensitivity of cell lines to anticancer drugs, based on the omics data of cell lines and the SMILES representations of drug molecules. First, we use statistical methods to compute the differences in gene expression, gene mutation, and gene copy number variations between within and outside biological pathways, and utilized these pathway difference values as cell line features, combined with the drugs' SMILES chemical structure information as inputs to the model. Then the model integrates various deep learning technologies multi-scale convolutional networks and transformer encoder to extract the properties of drug molecules from different perspectives, while an attention network is devoted to learning complex interactions between the omics features of cell lines and the aforementioned properties of drug molecules. Finally, a multilayer perceptron (MLP) outputs the final predictions of drug response. Our model exhibits higher accuracy in predicting the sensitivity to anticancer drugs comparing with other methods proposed recently. It is found that PARP inhibitors, and Topoisomerase I inhibitors were particularly sensitive to SCLC when analyzing the drug response predictions for lung cancer cell lines. Additionally, the model is capable of highlighting biological pathways related to cancer and accurately capturing critical parts of the drug's chemical structure. We also validated the model's clinical utility using clinical data from The Cancer Genome Atlas. In summary, the PASO model suggests potential as a robust support in individualized cancer treatment. Our methods are implemented in Python and are freely available from GitHub (https://github.com/queryang/PASO).

Deep Learning↗