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PubMed1988

Schizoid personality, inter-hemispheric transfer, and left hemisphere over-activation.

This study assesses the external validity of schizoid personality against multiple measures of cerebral laterality designed to distinguish between left hemisphere (LH) over-activation, LH damage and inter-hemisphere transfer deficit interpretations of schizotypy. Questionnaire measures of schizoid personality were assessed in an undergraduate population and related to laterality measures of both verbal and nonverbal dichotic listening, haptic inter- and intra-manual matching, employment of left and right hemisphere strategies during the haptic task, lateral eye-movements, and left and right ear auditory thresholds. A high score on a composite index of schizoid personality was significantly related to greater asymmetry (right ear advantage) in verbal dichotic listening, the use of LH strategies, and lower right ear thresholds, an overall pattern of results indicating LH over-activation in schizoids. It is suggested that studies comparing schizophrenic patients with normal controls minimize the likelihood of obtaining group differences if they fail to take into account schizoid personality in the controls.

Adult↗
PubMed1992

Improving psychotherapy services: applications of research, audit and evaluation.

Psychotherapy services face increasing demand but are vulnerable to critical scrutiny by service purchasers seeking evidence of cost-effectiveness. Psychotherapy research, although it can benefit practitioners, cannot adequately address these concerns because of poor external validity and it is argued that complementary strategies are needed. A number of service-based evaluative methods are reviewed and the distinctions clarified between service evaluation, operational research, professional audit, service audit, quality assurance and total quality management. Maxwell's (1984) six category framework is used to examine a number of issues in psychotherapy services including the assessment process, treatment-of-choice decisions, predicting negative effects of treatment, dose-response in psychotherapy, brief interventions, therapist competence, clinical significance, cost effectiveness and measures of psychotherapy service inputs, process and outcomes. This review advocates reflective practice within a self-evaluating psychotherapy service and a systemic approach which can take account of the perspectives of patients, purchasers, service managers, referrers and practitioners.

Follow-Up Studies↗
PubMed1978

Assessing the psychological effects of an exercise training programme for patients following myocardial infarction: a pilot study.

During a study investigating physiological and other effects of an exercise programme for coronary patients, a questionnaire was administered. Preliminary analysis had suggested some improvement in the patients' morale, but in view of the possible relevance of a number of psychological variables it was decided to carry out further analysis on the available data. The coefficient of discrimination was computed for 32 patients. For 19 patients correlations were computed between scores on subjective fitness, symptoms, anxiety, interest in sex, if at work, age, weight, and workload achieved at a given heart rate. The questionnaire appeared to have satisfactorily high internal and external validity. Patients with a high 'morale' score tended to achieve a greater increase in workload over the course. Although cause and effect cannot be unequivocally assigned, the association is felt to be important, and research is continuing.

Anxiety↗
PubMedDate not supplied

Analysis of biofluids in aqueous environment based on mid-infrared spectroscopy.

In this study we describe a semiautomatic Fourier transform infrared spectroscopic methodology for the analysis of liquid serum samples, which combines simple sample introduction with high sample throughput. The applicability of this new infrared technology to the analysis of liquid serum samples from a cohort of cattle naturally infected with bovine spongiform encephalopathy and from controls was explored in comparison to the conventional approach based on transmission infrared spectroscopy of dried serum films. Artifical neural network analysis of the infrared data was performed to differentiate between bovine spongiform encephalopathy-negative controls and animals in the late stage of the disease. After training of artifical neural network classifiers, infrared spectra of sera from an independent external validation data set were analyzed. In this way, sensitivities between 90 and 96% and specificities between 84 and 92% were achieved, respectively, depending upon the strategy of data collection and data analysis. Based on these results, the advantages and limitations of the liquid sample technique and the dried film approach for routine analysis of biofluids are discussed.

Algorithms↗
PubMed2006

Differentiation of Listeria monocytogenes serovars by using artificial neural network analysis of Fourier-transformed infrared spectra.

A classification system based on Fourier transform infrared (FTIR) spectroscopy combined with artificial neural network analysis was designed to differentiate 12 serovars of Listeria monocytogenes using a reference database of 106 well-defined strains. External validation was performed using a test set of another 166 L. monocytogenes strains. The O antigens (serogroup) of 164 strains (98.8%) could be identified correctly, and H antigens were correctly determined in 152 (91.6%) of the test strains. Importantly, 40 out of 41 potentially epidemic serovar 4b strains were unambiguously identified. FTIR analysis is superior to PCR-based systems for serovar differentiation and has potential for the rapid, simultaneous identification of both species and serovar of an unknown Listeria isolate by simply measuring a whole-cell infrared spectrum.

Bacterial Typing Techniques↗
PubMed2006

Reliable and rapid identification of Listeria monocytogenes and Listeria species by artificial neural network-based Fourier transform infrared spectroscopy.

Differentiation of the species within the genus Listeria is important for the food industry but only a few reliable methods are available so far. While a number of studies have used Fourier transform infrared (FTIR) spectroscopy to identify bacteria, the extraction of complex pattern information from the infrared spectra remains difficult. Here, we apply artificial neural network technology (ANN), which is an advanced multivariate data-processing method of pattern analysis, to identify Listeria infrared spectra at the species level. A hierarchical classification system based on ANN analysis for Listeria FTIR spectra was created, based on a comprehensive reference spectral database including 243 well-defined reference strains of Listeria monocytogenes, L. innocua, L. ivanovii, L. seeligeri, and L. welshimeri. In parallel, a univariate FTIR identification model was developed. To evaluate the potentials of these models, a set of 277 isolates of diverse geographical origins, but not included in the reference database, were assembled and used as an independent external validation for species discrimination. Univariate FTIR analysis allowed the correct identification of 85.2% of all strains and of 93% of the L. monocytogenes strains. ANN-based analysis enhanced differentiation success to 96% for all Listeria species, including a success rate of 99.2% for correct L. monocytogenes identification. The identity of the 277-strain test set was also determined with the standard phenotypical API Listeria system. This kit was able to identify 88% of the test isolates and 93% of L. monocytogenes strains. These results demonstrate the high reliability and strong potential of ANN-based FTIR spectrum analysis for identification of the five Listeria species under investigation. Starting from a pure culture, this technique allows the cost-efficient and rapid identification of Listeria species within 25 h and is suitable for use in a routine food microbiological laboratory.

Bacteriological Techniques↗
PubMed2006

Aspects of pain, its assessment and evaluation from an acupuncture perspective.

Pain is a major clinical problem that causes great suffering for the individual and incurs costs for society. Accurate assessment and evaluation of perceived pain is necessary for diagnosis, for choice of treatment, and for the evaluation of treatment efficacy. The assessment of an individual's pain is a challenge since pain is a subjective, multidimensional experience, and assessment is based on the person's own self-report. The results are often varied, possibly due to inter-individual variation, but also in relation to gender and aetiology. A gold standard for pain assessment is still lacking, but rating scales, questionnaires, and methods derived from psychophysical concepts, such as threshold assessments and perceptual matching, are used. In the evaluation of pain and associated variables, both systematic and individual variation should be taken into account, as should pain-associated symptoms. Recommendations for pain treatment should be based on the patient's specific needs. Therefore, it is important to assess the level of perceived pain taking individual variation into account. The methods used should preferably have proved to be useful in randomised controlled trials, and analysis of pain assessment should consider its non-metric properties. In the future, the use of studies with a naturalistic protocol together with individual assessment of individual pain responses could increase the internal and external validity.

Acupuncture Therapy↗
PubMed2003

Screening in brief intervention trials targeting excessive drinkers in general practice: systematic review and meta-analysis.

OBJECTIVE: To determine the effectiveness of programmes of screening in general practice for excessive alcohol use and providing brief interventions. DESIGN: Systematic review and meta-analysis of randomised controlled trials that used screening as a precursor to brief intervention. SETTING: General practice. MAIN OUTCOME MEASURES: Number needed to treat, proportion of patients positive on screening, proportion given brief interventions, and effect of screening. RESULTS: The eight studies included for meta-analysis all used health questionnaires for screening, and the brief interventions included feedback, information, and advice. The studies contained several sources of bias that might lead to overestimates of the effects of intervention. External validity was compromised because typically three out of four people identified by screening as excessive users of alcohol did not qualify for the intervention after a secondary assessment. Overall, in 1000 screened patients, 90 screened positive and required further assessment, after which 25 qualified for brief intervention; after one year 2.6 (95% confidence interval 1.7 to 3.4) reported they drank less than the maximum recommended level. CONCLUSIONS: Although even brief advice can reduce excessive drinking, screening in general practice does not seem to be an effective precursor to brief interventions targeting excessive alcohol use. This meta-analysis raises questions about the feasibility of screening in general practice for excessive use of alcohol.

Alcoholism↗
PubMed2004

What can experience add to early medical education? Consensus survey.

OBJECTIVE: To provide a rationale for integrating experience into early medical education ("early experience"). DESIGN: Small group discussions to obtain stakeholders' views. Grounded theory analysis with respondent, internal, and external validation. SETTING: Problem based, undergraduate medical curriculum that is not vertically integrated. PARTICIPANTS: A purposive sample of 64 students, staff, and curriculum leaders from three university medical schools in the United Kingdom. RESULTS: Without early experience, the curriculum was socially isolating and divorced from clinical practice. The abruptness of students' transition to the clinical environment in year 3 generated positive and negative emotions. The rationale for early experience would be to ease the transition; orientate the curriculum towards the social context of practice; make students more confident to approach patients; motivate them; increase their awareness of themselves and others; strengthen, deepen, and contextualise their theoretical knowledge; teach intellectual skills; strengthen learning of behavioural and social sciences; and teach them about the role of health professionals. CONCLUSION: A rationale for early experience would be to strengthen and deepen cognitively, broaden affectively, contextualise, and integrate medical education. This is partly a process of professional socialisation that should start earlier to avoid an abrupt transition. "Experience" can be defined as "authentic human contact in a social or clinical context that enhances learning of health, illness or disease, and the role of the health professional."

Attitude↗
PubMed2005

Socioeconomic gradients in the prevalence of cardiovascular disease in Scotland: the roles of composition and context.

OBJECTIVE: To investigate whether occupational social class and area deprivation are independently associated with the prevalence of cardiovascular disease (CVD) conditions after adjustment for smoking status. DESIGN: Stratified multistage random sample analysed using multilevel logistic regression. PARTICIPANTS: 8804 adults aged 18-74 at time of interview in 1998-1999, clustered in 312 small areas. The outcome considered was a self report of doctor diagnosis of one of a number of CVD conditions. The survey also provided information concerning the respondent's occupational social class and current smoking status. The Carstairs score (based on the 1991 census) was used to describe small area deprivation. MAIN RESULTS: The gradient in CVD prevalence across individual social class was attenuated and became insignificant when area deprivation was considered. The aggregation of individual social class and smoking to the area level increased the correlation with disease prevalence at the individual level. CONCLUSIONS: Although there is a relation between socioeconomic status and CVD prevalence in Scotland, the relation is dominated by area deprivation. When externally validated deprivation measures are not available, aggregated individual characteristics may show a contextual (as compared with compositional) relation.

Adolescent↗
PubMed2005

Diagnostic value of the Rotterdam-CAMCOG in post-stroke dementia.

BACKGROUND AND OBJECTIVE: Specific screening tests to detect post-stroke dementia are lacking. We recently reported that an adaptation of the Cambridge Cognitive Examination (CAMCOG), the Rotterdam-CAMCOG, had excellent sensitivity and specificity for detecting post-stroke dementia. In this study, we externally validated the diagnostic accuracy of the R-CAMCOG in a new, representative cohort of stroke patients. METHODS: The R-CAMCOG and an extensive neuropsychological examination were administered, independently of each other, in 121 patients aged 55 and over with a stroke in the preceding three to nine months. The gold standard diagnosis of dementia was based on the results of the extensive neuropsychological examination, clinical presentation, and information from a close relative, as well as DSM-IV criteria. RESULTS: Of the 121 patients, 35 had dementia (29%). The diagnostic accuracy at the pre-specified cut-off point of 33/34 was established through receiver operating characteristic (ROC) analyses (sensitivity 66%, specificity 94%). At a cut-off point of 36/37 sensitivity would be 83% and specificity 78%. CONCLUSION: The R-CAMCOG is a useful screening tool for post-stroke dementia in a clinical setting.

Aged↗
PubMed1993

Can the long term outcome of individual patients with transient ischaemic attacks be predicted accurately?

The prognosis of individual patients with transient ischaemic attacks (TIAs) is extremely variable; some patients are at high risk and others at low risk of a serious vascular event. Prediction equations of outcome were developed, based on eight clinical prognostic factors, from a cohort of 469 hospital-referred TIA patients ("training" data set), that enable high (and low) risk patients to be identified and for whom costly and risky treatments may (or may not) be targeted. The study aimed to determine whether these equations are externally valid and can predict outcome, with reliability and discrimination, in two independent cohorts of TIA patients ("test" data sets): 1653 TIA patients in the UK-TIA aspirin trial and 107 TIA patients in the Oxfordshire Community Stroke Project. Predicted outcomes agreed closely with the observed outcomes in the "test" data sets (reliability) for all outcome events at low five year risk (< 30%) but the estimates of risk were less precise in groups predicted to have a high five year risk (> 40%). The prediction equations were fairly accurate in discriminating between patients who subsequently suffered the outcome event of interest and those who survived free of the event at five years after the TIA, particularly at lower cut-off levels distinguishing high and low risk (for example, < 30% vs > 30% at five years). It is very difficult to achieve perfect discrimination because there is no single important prognostic factor for TIA patients that indicates whether a patient is going to suffer an event or not. These equations can be used to provide a reliable estimate of the absolute five year risk of a serious vascular event in hospital-referred TIA patients but they cannot, as yet, be used with confidence to distinguish patients at high risk from patients at low risk.

Aged↗
PubMed2002

Hazard potential ranking of hazardous waste landfill sites and risk of congenital anomalies.

BACKGROUND: A 33% increase in the risk of congenital anomalies has been found among residents near hazardous waste landfill sites in a European collaborative study (EUROHAZCON). AIMS: To develop and evaluate an expert panel scoring method of the hazard potential of EUROHAZCON landfill sites, and to investigate whether sites classified as posing a greater potential hazard are those with a greater risk of congenital anomaly among nearby residents relative to more distant residents. METHODS: A total of 1270 cases of congenital anomaly and 2308 non-malformed control births were selected in 14 study areas around 20 landfill sites. An expert panel of four landfill specialists scored each site in three categories-overall, water, and air hazard-based on readily available, documented data on site characteristics. Tertiles of the average ranking scores defined low, medium, and high hazard sites. Calculation of odds ratios was based on distance of residence from the sites, comparing a 0-3 km "proximate" with a 3-7 km "distant" zone. RESULTS: Agreement between experts measured by intraclass correlation coefficients was 0.50, 0.44, and 0.20 for overall, water, and air hazard before a consensus meeting and 0.60, 0.56, and 0.53 respectively after this meeting. There was no evidence for a trend of increasing odds ratios with increasing overall hazard or air hazard. For non-chromosomal anomalies, odds ratios by water hazard category showed an increasing trend of borderline statistical significance (p = 0.06) from 0.79 in the low hazard category, 1.43 in the medium, to 1.60 in the high water hazard category. CONCLUSIONS: There is little evidence for a relation between risk of congenital anomaly in proximate relative to distant zones and hazard potential of landfill sites as classified by the expert panel, but without external validation of the hazard potential scoring method interpretation is difficult. Potential misclassification of sites may have reduced our ability to detect any true dose-response effect.

Congenital Abnormalities↗
PubMed2004

The Asian Epidemic Model: a process model for exploring HIV policy and programme alternatives in Asia.

Process models offer opportunities to explore the effectiveness of different programme and policy alternatives by varying input behaviours and model parameters to reflect programmatic/policy effects. The Asian Epidemic Model (AEM) has been designed to reflect the primary groups and transmission modes driving HIV transmission in Asia. The user adjusts AEM fitting parameters until HIV prevalence outputs from the model agree with observed epidemiological trends. The AEM resultant projections are closely tied to the epidemiological and behavioural data in the country. In Thailand and Cambodia they have shown good agreement with observed epidemiological trends in surveillance populations and with changes in HIV transmission modes, AIDS cases, male:female ratios over time, and other external validation checks. By varying the input behaviours and STI trends, one can examine the impact of different prevention efforts on the future course of the epidemic. In conclusion, the AEM is a semi-empirical model, which has worked well in Asian settings. It provides a useful tool for policy and programme analysis in Asian countries.

Asia↗
PubMed2001

Empirically supported psychological interventions: controversies and evidence.

Efforts to increase the practice of evidence-based psychotherapy in the United States have led to the formation of task forces to define, identify, and disseminate information about empirically supported psychological interventions. The work of several such task forces and other groups reviewing empirically supported treatments (ESTs) in the United States, United Kingdom, and elsewhere is summarized here, along with the lists of treatments that have been identified as ESTs. Also reviewed is the controversy surrounding EST identification and dissemination, including concerns abou research methodology, external validity, and utility of EST research, as well as the reliability and transparency of the EST review process.

Humans↗
PubMed2005

Youth psychotherapy outcome research: a review and critique of the evidence base.

Over the past four decades, researchers have produced extensive evidence on psychotherapy for youth mental health problems and disorders. The evidence often has been evaluated through narrative reviews and through meta-analyses assessing the magnitude of treatment effects, but methodological analysis addressing the character and quality of the evidence base itself is an important complement, needed to place treatment effects in perspective and to suggest directions for future research. We carried out such an analysis, focusing on all the methodologically acceptable published randomized trials our search identified involving treatment of anxiety, depression, ADHD and related conditions, and conduct-related problems and disorders. The 236 studies tested 383 treatments and included 427 treatment-control comparisons, spanning the years 1962 through 2002. The analysis revealed considerable breadth, diversity, and rigor in the measurement approaches used to assess participant characteristics and treatment outcomes. However, reporting on important sample characteristics (e.g., ethnicity) showed major gaps, and more than half the studies failed to use well-standardized procedures to ensure appropriate sample selection. Because sample sizes left most studies underpowered, and procedures to enhance treatment fidelity were generally weak, many of the treatments investigated may not have received fair tests. Studies were particularly weak in clinical representativeness of their samples, therapists, and settings, suggesting a need for increased emphasis on external validity in youth treatment research.

Adolescent↗
PubMed2007

How can we increase translation of research into practice? Types of evidence needed.

This review summarizes key factors that have interfered with translation of research to practice and what public health researchers can do to hasten such transfer, focusing on characteristics of interventions, target settings, and research designs. The need to address context and to utilize research, review, and reporting practices that address external validity issues-such as designs that focus on replication, and practical clinical and behavioral trials-are emphasized. Although there has been increased emphasis on social-ecological interventions that go beyond the individual level, interventions often address each component as if it were an independent intervention. Greater attention is needed to connectedness across program levels and components. Finally, examples are provided of evaluation models and current programs that can help accelerate translation of research to practice and policy.

Decision Making, Organizational↗
PubMed2002

Use of natural language processing to translate clinical information from a database of 889,921 chest radiographic reports.

PURPOSE: To evaluate translation of chest radiographic reports by using natural language processing and to compare the findings with those in the literature. MATERIALS AND METHODS: A natural language processor coded 10 years of narrative chest radiographic reports from an urban academic medical center. Coding for 150 reports was compared with manual coding. Frequencies and co-occurrences of 24 clinical conditions (diseases, abnormalities, and clinical states) were estimated. The ratio of right to left lung mass, association of pleural effusion with other conditions, and frequency of bullet and stab wounds were compared with independent observations. The sensitivity and specificity of the system's pneumothorax coding were compared with those of manual financial coding. RESULTS: The system coded 889,921 reports on 251,186 patients. On the basis of manual coding of 150 reports, the processor's sensitivity (0.81) and specificity (0.99) were comparable to those previously reported for natural language processing and for expert coders. The frequencies of the selected conditions ranged from 0.22 for pleural effusion to 0.0004 for tension pneumothorax. The database confirmed earlier observations that lung cancer occurs in a 3:2 right-to-left ratio. The association of pleural effusion with other conditions mirrored that in the literature. Bullet and stab wounds decreased during 10 years at a rate consistent with crime statistics. A review of pneumothorax cases showed that the database (sensitivity, 1.00; specificity, 0.996) was more accurate than financial discharge coding (sensitivity, 0.17; P =.002; specificity, 0.996; not significant). CONCLUSION: Internal and external validation in this study confirmed the accuracy of natural language processing for translating chest radiographic narrative reports into a large database of information.

Databases, Factual↗