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PubMed1989

Validation of MMPI profile subtypes among opioid addicts who are beginning methadone maintenance treatment.

The purpose of the present research was (1) to examine the stability of MMPI subtypes within a VA drug abusing population; and (2) to provide external validation for these subtypes. The MMPI was administered to 107 male veterans who were entering methadone maintenance treatment. Normal sphere personality characteristics, sociodemographic information, and self- and interviewer ratings were collected by use of the Sixteen Personality Factor Questionnaire (16PF) and the Addiction Severity Index (ASI). Using D2 analysis, each MMPI profile was compared to the mean profile for three MMPI profile clusters obtained by Roszell, Chaney, and Blaes (1983) on a previous sample. Normal, psychoneurotic, and schizoid profiles were found in percentages similar to Roszell et al. The normal cluster was divided into two groups with and without T score elevations above 70 on the clinical scales. The normal group with profile elevations was similar to profile groups labeled as psychopathic in previous research. The four MMPI profile subtypes were compared on the 16PF and the ASI. The psychoneurotic and schizoid groups demonstrated higher levels of emotional distress and psychiatric difficulty than did the normal or psychopathic groups. The psychopathic and schizoid groups had more legal problems than the other two groups; the normal group had less evidence of marital and family problems.

Adult↗
PubMed2003

The validity of adolescent types of alcohol use.

BACKGROUND: Alcohol is the most frequently used substance among adolescents with different patterns of consumption. Various types of adolescent alcohol use have been proposed, but only a few studies have looked for external validation of these types. METHOD: Data from 794 adolescents participating in the Zurich Adolescent Psychology and Psychopathology Study (ZAPPS) were used to evaluate the discriminant validity of the classification of four types of adolescent drinkers: abstainers, social drinkers, heavy drinkers, and problem drinkers. Data were based on questionnaires dealing with substance abuse, emotional and behavioral problems, life events, coping capacity, self-related cognitions, perceived parental behavior, perceived school environment, and the social network. RESULTS: There was a clear differentiation of the problem drinkers' group on almost all dimensions of the emotional and behavioral problems questionnaires, with the heavy drinkers' profile situated in between on some dimensions, and the abstainers and social drinkers almost ideally meeting the expectation of a mean normal population profile. Problem drinkers were also marked by high life impact scores, low self-esteem, high self-awareness, low perceived parental acceptance and high amount of rejection by the parents, and various indicators of a stressful and less rewarding school environment. Again, the heavy drinkers were positioned on an intermediate level on some of these scales, whereas the abstainers and social drinkers scored more normally. CONCLUSION: These findings support the validity of the distinction of various adolescent alcohol use types.

Adolescent↗
PubMed2026

Integrative analysis of the roles and prognostic value of RNA-binding proteins in papillary renal cell carcinoma.

RNA-binding proteins (RBPs) serve essential roles in various cancer types, but their functions in papillary renal cell carcinoma (pRCC) have not been elucidated to date. In our work, differentially expressed RBPs in pRCC were identified after acquisition of RNA-sequencing and clinical data related to pRCC from The Cancer Genome Atlas database(TCGA). Functional enrichment analysis and protein interaction network analysis, along with univariate and multivariate Cox regression analyses, were performed to uncover potential biological effects of the identified RBPs and screen the hub RBPs for pRCC prognosis. We identified 251 up-regulated and 129 down-regulated RBPs, and filtered out seven hub RBPs, namely, SRSF8, CD3EAP, HBS1L, ELAC2, MRPL34, NOP2 and IGF2BP2, for their prognostic relevance. A prognostic risk score model for overall survival of pRCC patients was constructed based on the seven hub RBPs. Further analysis showed that the low-risk group had higher survival rate than the high-risk group in both training and validation cohorts. The predictive accuracy was verified in the Human Protein Atlas database.In addition, we introduced the GSE15641 dataset from the Gene Expression Omnibus (GEO) database for independent external validation, and confirmed the expression levels of HBS1L, MRPL34 and IGF2BP2 through real-time quantitative PCR (RT-qPCR) and Western blotting (WB) using human renal tubular epithelial cell line HK-2 and human papillary renal cell carcinoma cell line Caki-2. In pRCC, CD3EAP was significantly elevated, while ELAC2, IGF2BP2, MRPL34, SRSF8 and HBS1L were significantly reduced. There was no significant difference between tumor and normal tissues in NOP2 expression. Risk score and tumor grade were independent prognostic factors associated with overall survival. In addition, we established a nomogram based on the seven prognostic RBPs to help predict overall survival at 1-3 years. In conclusion, seven differentially expressed hub RBPs were identified as potential prognostic biomarkers for pRCC. Our prognostic model might serve as a support for better treatment decision-making. Our work could provide potential new ideas for diagnosis and research on targeted drugs for pRCC.

Bioinformatics↗
PubMed2002

Predicting toxicity of tall larkspur (Delphinium barbeyi): measurement of the variation in alkaloid concentration among plants and among years.

Tall larkspur (Delphinium barbeyi) is the principal mountain larkspur responsible for the majority of cattle deaths on mountain rangelands in western Colorado and central and southern Utah in the United States. Ten plants in each of two tall larkspur populations in the mountains near Ferron and Salina, Utah, were marked, and single stalks were harvested periodically through the growing season for 4 yr. Toxic alkaloid concentration [alkaloids containing the N-(methylsuccimimido)-anthranilik ester group] was determined by Fourier transform infrared (FTIR) spectroscopy. Individual larkspur plants varied in alkaloid concentrations, especially in early growth (14-38 mg/g). As the concentration declined over the growing season, variation among plants also declined. There were yearly differences in alkaloid concentration among individual plants (P < 0.01) and populations (P < 0.001), even after accounting for differences in phenological growth between years. Variables such as precipitation, temperature, days since snow melt, growing degree days (sum of mean temperature each day from snow melt), and plant height and weight were all considered in a Mallows Cp multiple regression selection procedure to predict alkaloid concentration. The mixed model procedure in SAS adjusted the regression equation for locations and years. Growing degree days was the best single predictor of alkaloid levels: In y = (3.581 - 0.00423 GDD), R2 = 0.85. Internal validation of this equation within individual years and locations from which the equation was developed, produced correlations between observed versus predicted values ranging from r = 0.73 to 0.93. External validations on nine other larkspur populations produced correlations ranging from r = 0.76 to 0.99. This predictive equation can provide a tool for ranchers and land managers to make management decisions of when to graze cattle in larkspur areas.

Alkaloids↗
PubMed1997

The development of an empirical psychosocial taxonomy for patients with diabetes.

The main purpose of this study was to develop and to cross-validate an empirically derived psychosocial taxonomy of patients with diabetes. In the first study, 101 patients with Type I or Type II diabetes completed the Multidimensional Diabetes Questionnaire. Cluster analysis identified three clusters, labeled adaptive copers, low support-low involvement, and spousal overinvolvement. In the second study, the taxonomy was cross-validated using an independent sample of 132 patients with long-standing Type II diabetes. The results confirmed that the multivariate classification system was unique and highly accurate. External validation, using general psychological as well as diabetes-specific measures, supported the validity and distinctiveness of the patients' profiles. These findings help establish a multiaxial psychosocial taxonomy of diabetes and may have significant implications for the management of patients with diabetes.

Adaptation, Psychological↗
PubMed2005

Development and validation of a questionnaire to identify learning-oriented group interactions in PBL.

Collaborative learning attracts attention because of its potential as a powerful learning strategy. This also holds for PBL. However, group work in PBL sometimes encounters problems and the quality of interaction is not always at the desired level. The aim of the present study was to develop and validate a questionnaire to assess the quality of learning-oriented group interactions in PBL in an uncomplicated way. The questionnaire, to be completed by students involved in PBL, contained items on three group-interaction dimensions: exploratory questions, cumulative reasoning and handling conflicts. It was validated by means of confirmatory factor analysis and regression analysis, the latter to investigate the relation between the three-dimension model and the tutorial group's productivity. The factors underlying the questionnaire were confirmed by the data in a linear structural analysis of the data. The regression analysis showed that the 'exploratory questions' and 'cumulative reasoning' factors explained together 26% of the variance of the tutorial group's productivity. This study provided evidence for the validity of the questionnaire. The instrument contains tips for students and tutors to stimulate deep processing interactions in the tutorial group. Nevertheless, it seems useful to investigate the external validity of the questionnaire.

Cooperative Behavior↗
PubMed2026

Digital and computational morphology in hematology: current platforms, clinical evidence, and future requirements.

INTRODUCTION: Morphologic examination of peripheral blood and bone marrow remains central to the diagnosis and classification of hematologic disorders. Conventional optical microscopy, however, is labor-intensive, dependent on operator expertise, and affected by interobserver variability. Digital morphology has developed from automated image acquisition and cell pre-classification into a broader field that includes whole-slide imaging, remote review, quantitative morphometry, and artificial intelligence-based analysis. CONTENT: This review examines current applications of digital morphology in peripheral blood, bone marrow aspirates, malaria detection, and body-fluid analysis. Commercial platforms are evaluated with particular attention to the distinction between raw automated pre-classification, expert digital post-classification, and comparison with independent optical microscopy. Digital systems generally perform well for common mature leukocyte populations but remain less reliable for rare or diagnostically critical cells, including blasts, abnormal lymphoid cells, plasma cells, and intermediate maturation stages. Research systems increasingly extend analysis from individual-cell classification to whole-slide, specimen-level, and patient-level assessment. SUMMARY: Digital morphology can improve standardization, image traceability, remote consultation, education, proficiency testing, quality assurance, and selected aspects of laboratory workflow. Its clinical value depends on appropriate validation, transparent reporting of reference methods, recognition of algorithm-specific failure modes, and clearly defined criteria for expert review and conventional microscopy. Human expertise remains essential not only for validating results but also for adapting cell taxonomies and interpretive rules to evolving classifications of hematologic diseases. OUTLOOK: Future progress will require representative multicenter datasets, harmonized morphologic terminology, external validation, interoperability with laboratory information systems, and continuous monitoring after software or hardware updates. Integration of morphology with quantitative hematology, flow cytometry, cytogenetics, genomics, and clinical data may support more comprehensive computational diagnosis. Digital platforms may also broaden access to specialist expertise, training, and quality programs in resource-limited institutions and regions, provided that infrastructure, governance, and professional competency are adequately supported.

artificial intelligence↗
PubMed2006

QSAR modeling of human serum protein binding with several modeling techniques utilizing structure-information representation.

Four modeling techniques, using topological descriptors to represent molecular structure, were employed to produce models of human serum protein binding (% bound) on a data set of 1008 experimental values, carefully screened from publicly available sources. To our knowledge, this data is the largest set on human serum protein binding reported for QSAR modeling. The data was partitioned into a training set of 808 compounds and an external validation test set of 200 compounds. Partitioning was accomplished by clustering the compounds in a structure descriptor space so that random sampling of 20% of the whole data set produced an external test set that is a good representative of the training set with respect to both structure and protein binding values. The four modeling techniques include multiple linear regression (MLR), artificial neural networks (ANN), k-nearest neighbors (kNN), and support vector machines (SVM). With the exception of the MLR model, the ANN, kNN, and SVM QSARs were ensemble models. Training set correlation coefficients and mean absolute error ranged from r2=0.90 and MAE=7.6 for ANN to r2=0.61 and MAE=16.2 for MLR. Prediction results from the validation set yielded correlation coefficients and mean absolute errors which ranged from r2=0.70 and MAE=14.1 for ANN to a low of r2=0.59 and MAE=18.3 for the SVM model. Structure descriptors that contribute significantly to the models are discussed and compared with those found in other published models. For the ANN model, structure descriptor trends with respect to their affects on predicted protein binding can assist the chemist in structure modification during the drug design process.

Blood Proteins↗
PubMedDate not supplied

The system of belief inventory (SBI-15): a validation study in Israel.

This study focused on the validation of measures assessing religiosity by means of three self-report instruments: the System of Belief Inventory (SBI-15R), the Religious Orientation Inventory (ROI), and the Index of Core Spiritual Experiences (INSPIRIT). These instruments were developed and validated previously in the United States. The study measured the extent to which the self-reports maintain their validity when administered in a different country with its own distinct language, culture and religion (e.g. Israel). It was found that all three self-reports have very good external validity and high convergent reliability, with the SBI demonstrating extremely high internal reliability.

Adult↗
PubMed1990

The Quality Assessment Index (QAI) for measuring nursing home quality.

There have been few detailed evaluations of measures of quality of care in nursing homes. This is unfortunate because it has meant that much research on factors affecting nursing home quality has used measures of questionable reliability and validity. Moreover, some measures currently in use have been developed using methodologies not based on solid conceptual grounds, offering little reason to expect them to have much internal or external validity. In this article we suggest characteristics that should be present in measures of nursing home quality, propose a methodology for the development of such measures, propose a specific nursing home quality measure (the Quality Assessment Index or QAI), and report the results of several tests of its validity and reliability.

Abstracting and Indexing↗
PubMed2004

Metrologic traceability of total thyroxine measurements in human serum: efforts to establish a network of reference measurement laboratories.

BACKGROUND: Assuring/demonstrating metrologic traceability of in vitro diagnostics necessitates the availability of measurand-specific reference measurement systems (RMSs) and the possibility for industry to work with competent reference measurement laboratories (RMLs). Here we report the results of a European project to investigate the feasibility of developing a RMS for serum total thyroxine. METHODS: Four candidate RMLs (cRMLs) developed/implemented variants of a candidate reference measurement procedure (cRMP) based on isotope dilution-liquid chromatography-mass spectrometry. The sole constraint implemented was calibration with a common thyroxine primary calibrator. The RMPs were externally validated and assessed for comparability in round-robin trials using common samples, i.e., 5 lyophilized and 33 frozen native sera. At the same time, the performance of the cRMLs organized in a network was assessed. For uniform external quality assessment, common performance specifications were agreed on. RESULTS: All cRMLs performed the cRMPs with fulfillment of the predefined specifications: total and between-laboratory CVs < or =2.0% and 2.5%, respectively, and a systematic deviation < or =0.9%, estimated with a target assigned from the mean of means obtained by the cRMLs. The mean expanded uncertainty for value assignment to the native sera was 2.1%. CONCLUSIONS: A network of cRMLs, with externally conformed competence to properly perform RMPs, has been established. Performance specifications were defined and will form the basis for admittance of new network members. A serum panel, successfully targeted during the validation process, is available for split-sample measurements with commercial routine measurement procedures. The model can now be used for other measurands for which traceability to the Systeme International d'Unites is needed.

Chromatography, Liquid↗
PubMed2006

Production and validation of durable, high quality standardized malaria microscopy slides for teaching, testing and quality assurance during an era of declining diagnostic proficiency.

BACKGROUND: Sets of Giemsa-stained, blood smear slides with systematically verified composite diagnoses would contribute substantially to development of externally validated quality assurance systems for the microscopic diagnosis of malaria. METHODS: whole blood from Plasmodium-positive donors in Cambodia and Indonesia and individuals with no history of risk for malaria was collected. Using standard operating procedures, technicians prepared Giemsa-stained thick and thin smears from each donor. One slide from each of the first 35 donations was distributed to each of 28 individuals acknowledged by reputation as having expertise in the microscopic diagnosis of malaria. These reference readers recorded presence or absence of Plasmodium species and parasite density. A composite diagnosis for each donation was determined based on microscopic findings and species-specific small subunit ribosomal RNA (ssrRNA) DNA polymerase chain reaction (PCR) amplification. RESULTS: More than 12,000 slides were generated from 124 donations. Reference readers correctly identified presence of parasites on 85% of slides with densities <100 parasites/microl, which improved to 100% for densities >350 parasites/microl. Percentages of agreement with composite diagnoses were highest for Plasmodium falciparum (99%), followed by Plasmodium vivax (86%). CONCLUSION: Herein, a standardized method for producing large numbers of consistently high quality, durable Giemsa-stained blood smears and validating composite diagnoses for the purpose of creating a malaria slide repository in support of initiatives to improve training and competency assessment amidst a background of variability in diagnosis is described.

Animals↗
PubMed1995

Predictive validity of subtypes of chronic affective disorders derived by cluster analysis.

This study aimed to examine the predictive validity of the cluster-analytically derived 3 subtypes of chronic affective disorders that were proposed on the basis of cross-sectional symptoms and were shown to have some external validity with regard to psychosocial characteristics. Two-year naturalistic follow-up data were available for 38 (97%) of the original 39 patients with chronic affective disorders. The 3 subtypes, which were named psychotic subtype, late-onset female subtype and depressive personality subtype in the previous analyses, did not differ in their depressive severity or social functioning upon entry. In the course of the 2-year follow-up, however, there were significant differences in the Global Assessment of Functioning scores as well as the social adaptation in the economic sphere according to the Social Adjustment Scale-Self Report. All these indices revealed the psychotic subtype to have the worst outcome, followed by the depressive personality subtype, and the late-onset female subtype fared best.

Adult↗
PubMed2005

Pilot study of the differences among the Puerto Rican aged by gender in opinion, attitude and exposure to abuse, mistreatment and neglect.

OBJECTIVES: Contribute to the knowledge base of the risk factor literature by gender for abuse, mistreatment and neglect of the Puerto Rican aged. BACKGROUND: A review of the literature in Puerto Rico and the United States related to gender impacting upon elder abuse, mistreatment and neglect report conflicting findings. METHODS: A 107 item questionnaire was developed. The definitions of abuse, mistreatment and neglect were based on those set out by the National Center on Elder Abuse in the United States (1998). The questionnaire has been preliminarily validated by Cronbach's Alpha .879. The sample of respondents was based upon availability. This method was selected in the face of practical considerations in spite of criticism to the external validity that this type of sample represents. Structured face to face interviews were carried out from August to December 2004 with 430 aged residing in community. Data were entered into the SPSS program whereby cross tabulations were carried out for gender. RESULTS: Elderly Puerto Ricans regardless of gender are knowledgeable concerning what constitutes attributes of abuse, mistreatment and neglect. Females were found to report a high percentage of yes responses than males to opinion statements related to situations of abuse, mistreatment and neglect. Males reported a higher percentage of yes responses to situations of exposure to abuse and neglect than females. CONCLUSIONS: Findings here are similar to some reported in the United States but are dissimilar to those reported in Puerto Rico. Further research must be carried out to pinpoint the living arrangements situations placing the aged in greatest risk for abuse and neglect. Such findings have implications for social policy, prevention and intervention strategies.

Aged↗
PubMed1996

The Glasgow Coma Scale: a critical appraisal of its clinimetric properties.

The Glasgow Coma Scale is a commonly used instrument in clinical practice. This article examines the published evidence to assess whether the scale possesses the requisite clinimetric properties. Articles describing and using the scale were located through a MEDLINE search. The clinimetric properties of the scale were appraised using the methodological principles of sensibility, reliability, validity, and responsiveness. The scale has a good sensibility and reliability (intraclass correlation coefficient, 0.8 to 1 for trained users). It has a well-established cross-sectional construct validity. Its predictive validity in traumatic coma, when combined with age and brainstem reflexes, is good in the generating sample (sensitivity, 79 to 97%; specificity, 84-97%) but has not been tested in an external validation sample. Its longitudinal construct validity has not been studied adequately. Thus, the scale is an established discriminative instrument but its validity as a predictive and an evaluative instrument has not yet been studied adequately.

Coma↗
PubMed2005

Non-stochastic and stochastic linear indices of the molecular pseudograph's atom-adjacency matrix: a novel approach for computational in silico screening and "rational" selection of new lead antibacterial agents.

A novel approach (TOMOCOMD-CARDD) to computer-aided "rational" drug design is illustrated. This approach is based on the calculation of the non-stochastic and stochastic linear indices of the molecular pseudograph's atom-adjacency matrix representing molecular structures. These TOMOCOMD-CARDD descriptors are introduced for the computational (virtual) screening and "rational" selection of new lead antibacterial agents using linear discrimination analysis. The two structure-based antibacterial-activity classification models, including non-stochastic and stochastic indices, classify correctly 91.61% and 90.75%, respectively, of 1525 chemicals in training sets. These models show high Matthews correlation coefficients (MCC=0.84 and 0.82). An external validation process was carried out to assess the robustness and predictive power of the model obtained. These QSAR models permit the correct classification of 91.49% and 89.31% of 505 compounds in an external test set, yielding MCCs of 0.84 and 0.79, respectively. The TOMOCOMD-CARDD approach compares satisfactorily with respect to nine of the most useful models for antimicrobial selection reported to date. Finally, an in silico screening of 87 new chemicals reported in the anti-infective field with antibacterial activities is developed showing the ability of the TOMOCOMD-CARDD models to identify new lead antibacterial compounds.

Algorithms↗
PubMed1998

Early detection of social interaction problems: development of a social interaction instrument in young children.

Children with developmental or psychiatric disorders often have problems with social interaction. This study reports on the development of the Ghuman-Folstein Screen for Social Interaction (SSI), a parent/caregiver questionnaire designed to measure the capacity for basic social interaction skills across a variety of contexts in preschool children. The SSI was administered to 51 clinically referred children with a high probability of deficits in social interaction and 60 healthy control subjects to establish reliability and validity. The children were 24 to 61 months of age, with diverse ethnic and socioeconomic backgrounds. Strong internal consistency, significant correlation for test/retest reliability, moderate correlation for interrater reliability and support for external validity of the SSI was established. The SSI scores differentiated between the clinically referred subjects and healthy control subjects and between children with pervasive developmental disorder (PDD) of the autistic type and other non-PDD developmental disorders. The SSI is a relatively simple, efficient, reliable, and valid measure for the capacity for basic social interaction skills in children 24 months to 5 years of age. The SSI has a potential to be useful in primary health care settings to identify children at risk who may need tracking and/or further evaluation and treatment services.

Child Behavior↗
PubMed1999

Self-reported assessment of visual function in a population-based study: the SEE project. Salisbury Eye Evaluation.

PURPOSE: To report on the usefulness of the Activities of Daily Vision Scale (ADVS) questionnaire for assessing visual functioning, a population-based sample of elderly Americans. METHODS: The ADVS questionnaire was administered to a population-based sample of 2520 community-dwelling individuals 65 to 84 years of age in Salisbury, MD. Items and subscales were evaluated for internal consistency, item discrimination, and content validity. Published subscale groupings and item associations in our population were compared for coherence using correlation, factor, and cluster analyses. Whole-sample and race- and gender-specific analyses were conducted. External validity was explored by regressing ADVS scores on standard psychophysical vision measures. RESULTS: ADVS scores were skewed to high visual functioning levels; approximately 60% of the population had function scores of 95 or better (of a possible 100). The overall, night driving, and near vision scales were internally consistent and had strong item-subscale associations; the day driving and glare subscales were not acceptable regarding these properties. The far vision subscale was acceptably scalable but only weakly differentiated from the other subscales. Overall, night driving, near vision, and far vision scores were all statistically and independently associated with multiple psychophysical vision measures. Findings were consistent across race and gender subgroups. CONCLUSIONS: As assessed by the ADVS, reported visual functioning is high in our representative older population. The overall scale and selected subscales effectively distinguish persons along a spectrum of ability. They correlate with measures of visual impairment in a reasonable way and thus hold promise for risk factor investigations. The published day driving and glare subscales should be examined for relevance and consistency before being applied in population-based settings. Methods specific to population-based settings should be investigated for their ability to better elicit additional visual function dimensions and early visual disability.

Activities of Daily Living↗