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PubMedDate not supplied

A mathematical typology analysis of DSM-III-R personality disorder classification: grade of membership technique.

This study employed grade of membership (GoM) analysis in a clinical setting to determine if the DSM-III-R personality disorder (PD) diagnostic criteria cluster into recognizable disorders resembling the official axis II nosology. The GoM model, based on fuzzy-set theoretic concepts, explicitly examines medical diagnostic systems by quantitatively identifying and characterizing subpatterns of illness within a broad class. A semistructured assessment of 110 outpatients was performed for 12 PDs and their 112 diagnostic criteria. GoM analysis was performed using internal variables of the 112 PD criteria rated as present or absent. Demographic variables, axis I and II diagnosis (structured clinical Interview for DSM [SCID]), and treatment response (Global Adjustment Scale [GAS]) information were used as external validators. Four pure types (PT) provided the most satisfactory solution to the data. PT-I is characterized by marked maladaptive personality pathology, which is manipulative, egocentric, impulsive, and alloplastic. PT-II consists primarily of exaggerated socially anxious and detached traits. PT-III is sociably dependent and autoplastic. PT-IV is essentially asymptomatic. GoM provides a more parsimonious handling of the PD criteria than provided by classifying according to DSM categories. The analysis fails to confirm the natural occurrence of any single specific axis II PD or cluster.

Adult↗
PubMed1999

Determination of cholesterol in atherosclerotic plaques using near infrared diffuse reflection spectroscopy.

The aim of this investigation was to examine whether near infrared diffuse reflection spectroscopy is an acceptable tool for the determination of cholesterol content in atherosclerotic plaques. Using an FT-spectrophotometer (lambda=1000-2500 nm) and fiberoptic systems (d=4 mm), the cholesterol content could be determined in mixtures of the primary compounds of the aortic wall with acceptable precision. Considering the inhomogeneous distribution of cholesterol and cholesterol esters in atherosclerotic plaques the determination of total cholesterol using this method is of acceptable efficacy, even though the calibration procedure did not reflect the composition correctly. Using an energy dose of less than 100 mW/cm(2) to avoid damage to endothelial cells, arterial tissue of about 170-200 microm thickness attenuates the reflected NIRS signal by up to 50%. Cholesterol levels could be determined accurately in atherosclerotic lesions in human aortic specimens obtained by autopsy. The correlation coefficient between the NIRS results and those of HPLC analysis calculated in the investigation of 82 different areas of 18 human aortic specimens was 0.926 (y=0.869x+0. 771, external validation). Acceptable results were also achieved by means of a coronary-catheterlike fiberoptic strand (d=l mm), despite the worsened signal/noise ratio. The results show that the development of a coronary catheter using NIRS appears to be possible in principle.

Arteriosclerosis↗
PubMed1999

Screening for somatization and hypochondriasis in primary care and neurological in-patients: a seven-item scale for hypochondriasis and somatization.

The aim of this study was to investigate the internal and external validity of the Whiteley Index as a screening instrument for somatization illness. A 14-item version of the Whiteley Index for hypochondriacal traits was given to 99 of 191 consecutive primary care patients, aged 18-65 years, and to 100 consecutive patients, aged 18-60 years, admitted for the first time to a neurological ward. The primary care sample was, in addition, interviewed by means of the SCAN (Schedules for Clinical Assessment in Neuropsychiatry) psychiatric interview. The GPs and the neurologists were asked to rate various characteristics of the patients that might indicate somatization. The internal validity of the Whiteley Index was tested by means of latent structure analysis. On this basis, a reduced seven-item scale (Whiteley-7 scale) and two subscales (i.e., an Illness Conviction and Illness Worrying scale, each with three items) were constructed. All three had a high internal validity fitting into the very restricted Rasch statistical model (p>0.05) and an acceptable transferability between most of the subpopulations investigated. In the primary care population, the Whiteley-7 and the Illness Conviction scales at cut-point 0/1 showed 1.00 and 0.87 sensitivity and 0.65 and 0.87 specificity, respectively, using as "gold standard" the fulfillment of criteria for at least one ICD-10 somatoform disorder, and 0.71 and 0.63 sensitivity and 0.62 and 0.87 specificity, respectively, as gold standard for the fulfillment of criteria for at least one DSM-IV somatoform disorder, excluding the NOS diagnostic group. The Illness Worrying subscale showed less impressive performance in this respect. The agreement between the Whiteley-7 scale including the two subscales and neurologists' rating and the GPs' rating and the somatization subscale on the SCL-90 was modest or worse. It may be concluded that the Whiteley-7 scale and the Illness Conviction subscale had acceptable psychometric profiles, and both seem to be promising screening tools for not only hypochondriasis but also for somatoform disorders in general.

Adolescent↗
PubMed2002

Cerclage and cervical insufficiency: an evidence-based analysis.

Since the cervical cerclage was introduced to clinical practice 50 years ago, the efficacy of the operation has not been established by evidence-based standards for many indications. Serious flaws in the methods employed to study the safety and efficacy of cerclage have led to confusion and misuse of the operation, although some investigators maintain that current standards make randomized clinical trials of this traditional surgery unethical. At present, five randomized clinical trials have offered significant information about elective cerclages performed for historical indications, and the expected neonatal survival rate with properly selected elective cerclages is around 87%. Transvaginal ultrasound studies have revealed new paradigms regarding normal cervical function in pregnancy and further understanding about the significance and predictive value of cervical changes at gestational ages between 20-37 weeks. Only two randomized clinical trials have been conducted regarding cerclage in women with decreasing cervical length or with cervical funneling. One of these two failed to demonstrate any resulting improvement in neonatal survival, and the other was too small to be conclusive. To date, no randomized clinical trials have been conducted to demonstrate the efficacy or safety of emergency cerclages performed for advanced cervical dilatation. The many retrospective case series regarding emergency cerclage have failed to provide an evidence-based solution to the management of this problem. Before this traditional surgery continues extensive use in clinical practice, it should be assessed rigorously with randomized clinical trials of sufficient statistical power and external validity to establish the appropriate indications for the operation. In addition, a more thorough understanding of cervical function and molecular biology is essential.

Abortion, Habitual↗
PubMedDate not supplied

A proposed scoring system for predicting mortality in melioidosis.

Melioidosis, due to infection with the environmental organism Burkholderia pseudomallei, continues to be associated with high mortality despite improvements in antibiotic therapy. Using simple clinical findings and baseline laboratory tests available at the time of admission, we attempted to define those patients with acute melioidosis who were at higher risk of death. Using data, collected prospectively from the period October 1989 to June 2002, from patients with acute culture-confirmed melioidosis presenting at the Royal Darwin Hospital, Darwin, Australia, a number of variables were selected that were easily available at the time of admission and reflected organ dysfunction. Mortality was predicted in univariate logistic and multivariate models by the presence of pneumonia, age at diagnosis, serum urea, serum bilirubin, lymphocyte count, and serum bicarbonate. A score was assigned from 0 to 2, based on the degree of abnormality. A melioidosis score was formed from the sum of these scores, with a maximum score of 11. A score of < or = 3 (n = 140) was associated with a mortality of 8.6%, whereas a score of > or = 4 (n = 112) was associated with a mortality of 44.6%. Although this scoring system requires external validation, it may help identify a suitable target group of patients for intensive intervention such as early admission to an intensive care unit, the early use of meropenem, and goal-directed resuscitation therapies.

Female↗
PubMed2002

Development of chlorine dioxide-related by-product models for drinking water treatment.

Factorial experiments were conducted using source waters from seven drinking water treatment plants in Ontario, Canada to develop statistically based model equations capable of predicting chlorine dioxide consumption and chlorite and chlorate formation upon chlorine dioxide application. The equations address raw water quality and operational parameters including pH, temperature, chlorine dioxide concentration, reaction time and water organic content (as described by non-purgeable organic carbon x ultraviolet absorbance measured at 254 nm, NPOC x UV254). Terms describing two-factor interaction effects were also included, improving the accuracy of the predictive equations in fitting measured response concentrations as evaluated through internal and external validations. Nearly 80% of the predictions for chlorine dioxide consumption and chlorite formation were observed to be within 20% of the measured levels. Over 90% of the predicted chlorate levels were within +/- 0.1 mg/L of the measured levels. Chlorine dioxide concentration and NPOC x UV254 were key parameters when developing the predictive models.

Carbon↗
PubMed2003

Geochemistry of some rare earth elements in groundwater, Vierlingsbeek, The Netherlands.

Groundwater samples were taken from seven bore holes at depths ranging from 2 to 41m nearby drinking water pumping station Vierlingsbeek, The Netherlands and analysed for Y, La, Ce, Pr, Nd, Sm and Eu. Shale-normalized patterns were generally flat and showed that the observed rare earth elements (REE) were probably of natural origin. In the shallow groundwaters the REEs were light REE (LREE) enriched, probably caused by binding of LREEs to colloids. To improve understanding of the behaviour of the REE, two approaches were used: calculations of the speciation and a statistical approach. For the speciation calculations, complexation and precipitation reactions including inorganic and dissolved organic carbon (DOC) compounds, were taken into account. The REE speciation showed REE(3+), REE(SO(4))(+), REE(CO(3))(+) and REE(DOC) being the major species. Dissolution of pure REE precipitates and REE-enriched solid phases did not account for the observed REEs in groundwater. Regulation of REE concentrations by adsorption-desorption processes to Fe(III)(OH)(3) and Al(OH)(3) minerals, which were calculated to be present in nearly all groundwaters, is a probable explanation. The statistical approach (multiple linear regression) showed that pH is by far the most significant groundwater characteristic which contributes to the variation in REE concentrations. Also DOC, SO(4), Fe and Al contributed significantly, although to a much lesser extent, to the variation in REE concentrations. This is in line with the calculated REE-species in solution and REE-adsorption to iron and aluminium (hydr)oxides. Regression equations including only pH, were derived to predict REE concentrations in groundwater. External validation showed that these regression equations were reasonably successful to predict REE concentrations of groundwater of another drinking water pumping station in quite different region of The Netherlands.

Adsorption↗
PubMed2001

Reliable QSAR for estimating Koc for persistent organic pollutants: correlation with molecular connectivity indices.

Several recent studies have shown that n-octanol/water partition coefficients may not be a good predictor for estimating soil sorption coefficients of persistent organic pollutants (POPs), defined here as chemicals with log Kow greater than 5. Thus, an alternative QSAR model was developed that seems to provide reliable estimates for the soil sorption coefficients of persistent organic pollutants. This model is based on a set of calculated molecular connectivity indices and evaluated soil sorption data for 18 POPs. The chemical's size and shape, quantified by 1chi, 3chiC and 4chiC(v) indices, have a dominant effect on the soil sorption process of POPs. The developed QSAR model was rationalized in terms of potential hydrophobic interactions between persistent organic pollutants and soil organic matrix. Its high predictive power has been verified by an extensive internal and external validation procedure.

Absorption↗
PubMed2000

Cost effectiveness of microwave thermotherapy in patients with benign prostatic hyperplasia: part I-methods.

OBJECTIVES: To present the method used to evaluate the cost effectiveness, from the societal perspective, of transurethral microwave thermotherapy relative to medical therapy (alpha-blocking agents) and transurethral resection of the prostate (TURP) for a hypothetical cohort of 65-year-old men with moderate-to-severe benign prostatic hyperplasia (BPH) symptoms. METHODS: We constructed a decision-analytic Markov model with 25 health states describing the 3 treatments, 5 short-term clinical events, and 17 possible long-term outcomes. Each health state had an associated cost and utility. Utility weights, reflecting an individual's preference for a specific health outcome, range from 0, indicating death, to 100, indicating perfect health. Utility estimates were obtained by interviewing 13 men with moderate-to-severe BPH symptoms using the standard gamble preference measurement technique. On the basis of their risk attitudes, the patients were classified as risk averse or non-risk averse. The rates of remission, temporary and permanent adverse events, retreatment, and mortality were obtained from the Targis System (Urologix) randomized clinical trial, published reports, and a consensus panel. The costs during the 5 years after treatment initiation were estimated using national Medicare reimbursement schedules. The costs are reported in 1999 U.S. dollars. RESULTS: Eliciting utility values from patients with BPH was feasible and generated internally consistent and externally valid measures. In the non-risk-averse group, the utility value for significant remission, moderate remission, no remission, and worsening BPH symptoms without an adverse event was 99.1, 97.1, 94.4, and 87.3, respectively. As expected, the risk-averse individuals (n = 6) exhibited higher utility values than those in the non-risk-averse group (n = 7). In the non-risk-averse group, thermotherapy was the preferred treatment, and in the risk-averse group, medical therapy was preferred. In both groups, TURP was the least preferred therapy. The initial thermotherapy procedure costs without complications were estimated at $2629, and the initial TURP procedure costs without complications were estimated at $4597. Time-dependent probabilities were developed to reflect treatment durability. CONCLUSIONS: The resulting model parameters appear to be suitable for evaluating the cost effectiveness of thermotherapy relative to medical therapy and TURP in 65-year-old men with moderate-to-severe BPH symptoms.

Adrenergic alpha-Antagonists↗
PubMed2003

A review of 25 long-term adolescent tobacco and other drug use prevention program evaluations.

BACKGROUND: Although the initial effectiveness of psychosocial strategies programming in preventing smoking and other drug abuse among adolescents has been well established through literature reviews and meta-analyses, much less evidence exists for the long-term follow-up success of these interventions. The primary goal of this paper, therefore, is to summarize the effectiveness of published program evaluation studies that have followed adolescents across the transitional period between junior high and high school for a period of at least 2 years. METHODS: Studies for inclusion in this review were accessed primarily through a computerized search of Medline, Healthstar, and PsychINFO databases. Intervention studies that met five core criteria were retained for review. Two authors independently abstracted data on study characteristics, methodology, and program outcomes. RESULTS: Search results yielded 25 studies suitable for examination. The majority of these studies reported significant program effects for long-term smoking, alcohol, and marijuana outcomes, while indicating a fairly consistent magnitude of program effects. CONCLUSIONS: This review provides long-term empirical evidence of the effectiveness of social influences programs in preventing or reducing substance use for up to 15 years after completion of programming. However, this conclusion is still somewhat tenuous given the lack of significant program effects reported in several studies and the great variability that existed in the level of internal and external validity across all studies.

Adolescent↗
PubMed2001

A three-item scale for the early prediction of stroke recovery.

BACKGROUND: Accurate assessment of prognosis in the first hours of stroke is desirable for best patient management. We aimed to assess whether the extent of ischaemic brain injury on magnetic reasonance diffusion-weighted imaging (MR DWI) could provide additional prognostic information to clinical factors. METHODS: In a three-phase study we studied 66 patients from a North American teaching hospital who had: MR DWI within 36 h of stroke onset; the National Institutes of Health Stroke Scale (NIHSS) score measured at the time of scanning; and the Barthel Index measured no later than 3 months after stroke. We used logistic regression to derive a predictive model for good recovery. This logistic regression model was applied to an independent series of 63 patients from an Australian teaching hospital, and we then developed a three-item scale for the early prediction of stroke recovery. FINDINGS: Combined measurements of the NIHSS score (p=0.01), time in hours from stroke onset to MR DWI (p=0.02), and the volume of ischaemic brain tissue on MR DWI (p=0.04) gave the best prediction of stroke recovery. The model was externally validated on the Australian sample with 0.77 sensitivity and 0.88 specificity. Three likelihood levels for stroke recovery-low (0-2), medium (3-4), and high (5-7)-were identified on the three-item scale. INTERPRETATION: The combination of clinical and MR DWI factors provided better prediction of stroke recovery than any factor alone, shortly after admission to hospital. This information was incorporated into a three-item scale for clinical use.

Activities of Daily Living↗
PubMed2001

A simple risk index for rapid initial triage of patients with ST-elevation myocardial infarction: an InTIME II substudy.

BACKGROUND: Rapid, effective triage is integral to emergency cardiac care of patients with ST-elevation myocardial infarction (STEMI). Available models for predicting mortality in STEMI include up to 45 variables, but have consistently shown advanced age, increased heart rate, and decreased blood pressure to be among the strongest predictors. METHODS: On the basis of observed risk relations among 13,253 patients with STEMI from the InTIME II trial, we developed and assessed a simple risk index using age, heart rate, and systolic blood pressure (SBP) for predicting mortality over 30 days: (heart rate x [age/10](2))/SBP. FINDINGS: The risk index was a strong (c statistic=0.78) and independent predictor of mortality risk (p<0.0001). When the risk index was categorised into quintiles for convenient clinical use, it revealed a more than 20-fold gradient of increasing mortality from 0.8 to 17.4%, p<0.0001. The risk index was also a robust predictor of very early events, including death by 24 h (c statistic=0.81). External validation in patients with STEMI from the TIMI 9 trials (n=3659) showed both a high discriminatory capacity (c statistic=0.79), and excellent concordance between the observed 30-day mortality in each of the five risk groups and the predictions based on InTIME II (goodness-of-fit, p=0.7). INTERPRETATION: A simple risk index based on characteristics easily assessed by any paramedical or clinical personnel captures most of the information from more complex tools, and is likely to be useful in the rapid triage of patients with STEMI outside hospital or on first arrival in the hospital.

Age Factors↗
PubMed2003

Gene expression predictors of breast cancer outcomes.

BACKGROUND: Correlation of risk factors with genomic data promises to provide specific treatment for individual patients, and needs interpretation of complex, multivariate patterns in gene expression data, as well as assessment of their ability to improve clinical predictions. We aimed to predict nodal metastatic states and relapse for breast cancer patients. METHODS: We analysed DNA microarray data from samples of primary breast tumours, using non-linear statistical analyses to assess multiple patterns of interactions of groups of genes that have predictive value for the individual patient, with respect to lymph node metastasis and cancer recurrence. FINDINGS: We identified aggregate patterns of gene expression (metagenes) that associate with lymph node status and recurrence, and that are capable of predicting outcomes in individual patients with about 90% accuracy. The metagenes defined distinct groups of genes, suggesting different biological processes underlying these two characteristics of breast cancer. Initial external validation came from similarly accurate predictions of nodal status of a small sample in a distinct population. INTERPRETATION: Multiple aggregate measures of profiles of gene expression define valuable predictive associations with lymph node metastasis and disease recurrence for individual patients. Gene expression data have the potential to aid accurate, individualised, prognosis. Importantly, these data are assessed in terms of precise numerical predictions, with ranges of probabilities of outcome. Precise and statistically valid assessments of risks specific for patients, will ultimately be of most value to clinicians faced with treatment decisions.

Adult↗
PubMedDate not supplied

The Quality Improvement for Depression collaboration: general analytic strategies for a coordinated study of quality improvement in depression care.

It is difficult to evaluate the promise of primary care quality-improvement interventions for depression because published studies have evaluated diverse interventions by using different research designs in dissimilar populations. Preplanned meta-analysis provides an alternative to derive more precise and generalizable estimates of intervention effects; however, this approach requires the resolution of analytic challenges resulting from design differences that threaten internal and external validity. This paper describes the four-project Quality Improvement for Depression (QID) collaboration specifically designed for preplanned meta-analysis of intervention effects on outcomes. This paper summarizes the interventions the four projects tested, characterizes commonalities and heterogeneity in the research designs used to evaluate these interventions, and discusses the implications of this heterogeneity for preplanned meta-analysis.

Adult↗
PubMedDate not supplied

Research to improve the quality of care for depression: alternatives to the simple randomized clinical trial.

Recognition of gaps between evidence gained from mental health research and clinical practice in the community together with changes in treatment patterns and patient/provider preferences for care have led to interest in enhancements in the designs and analyses of clinical and community trials of mental health interventions. Gaps between clinical trials and community care include differences in populations and treatment strategies. To bridge these gaps, we propose enhancing the simple randomized trial with several different designs with the immediate aims of improving patient recruitment and adherence in psychiatric intervention studies thus bringing study designs more in line with clinical practice. The goals are to estimate treatment efficacy and effectiveness so that both internal and external validity are optimized. In this discussion, we address design and analytic issues with respect to a number of enhancements of the randomized trial design, including partial patient-provider preference designs, randomized encouragement and consent designs, fixed adaptive design, and random between- and within-patient adaptive designs. Each has advantages and disadvantages depending on the effect under investigation. Some of these enhancements, such as the fixed adaptive design, have begun to be implemented in effectiveness trials in mental health services research, but all are worthy of more attention.

Depression↗
PubMed2001

Suicidal ideation among medical students and young physicians: a nationwide and prospective study of prevalence and predictors.

BACKGROUND: Despite an increased risk of suicide among physicians we lack studies on prevalence and predictors of suicidal ideation among medical students and young doctors. METHOD: A prospective study of Norwegian medical students (n=522) re-examined after the first postgraduate year, comprising suicidal thoughts and attempts, perceived study stress, job stress, and personality. RESULTS: The previous year prevalence of suicidal thoughts was 14% at both points of time. The lifetime prevalence was 43%, while 8% had planned suicide, and 1.4% had attempted suicide. Suicidal ideation in medical school was predicted by lack of control, personality trait, single marital status, negative life events and mental distress (anxiety and depression). In the first postgraduate year, mental distress was the most important predictor, but before controlling for this variable, job stress, vulnerability (neuroticism), single status, and less working hours were independent predictors. Prospectively, suicidal thoughts and vulnerability as student predicted postgraduate suicidal ideation. CONCLUSIONS: The level of suicidal thoughts was high, but the level of attempts was low. CLINICAL IMPLICATIONS: Preventive efforts should be directed both at the students' abilities to cope with stress and at mental health services for young doctors. LIMITATIONS OF STUDY: The lower response rate at follow-up (57%) may reduce external validity.

Adaptation, Psychological↗
PubMed2001

Principles of effectiveness trials and their implementation in VA Cooperative Study #430: 'Reducing the efficacy-effectiveness gap in bipolar disorder'.

Despite the availability of efficacious treatments for bipolar disorder, their effectiveness in general clinical practice is greatly attenuated, resulting in what has been called an 'efficacy-effectiveness gap'. In designing VA Cooperative Studies Program (CSP) Study #430 to address this gap, nine principles for conducting an effectiveness (in contrast to an efficacy) study were identified. These principles are presented and discussed, with specific aspects of CSP #430 serving as illustrations of how they can be implemented in an actual study. CSP #430 hypothesizes that an integrated, clinic-based treatment delivery system that emphasizes (1) algorithm-driven somatotherapy, (2) standardized patient education, and (3) easy access to a single primary mental health care provider to maximize continuity-of-care, will address the efficacy-effectiveness gap and improve disease, functional, and economic outcome. It is an 11-site, randomized controlled clinical trial of this multi-modal, clinic-based intervention versus usual VA care running from 1997 to 2003. The trial has enrolled 191 subjects in each arm, using minimal exclusion criteria to maximize the external validity of the study. Subjects are followed for 3 years. The intervention is highly specified in a series of operations manuals for each of the three components. Several continuous quality improvement (CQI) interventions, process measures, and statistical techniques deal with drift of care in both the intervention and usual care arms to ensure the internal validity of the study. CSP #430 is designed to have impact well beyond the VA, since it evaluates a basic health care operational principle: that augmenting ambulatory access for major mental illness will improve outcome and reduce overall treatment costs. If results are positive, this study will provide a reason to reconsider the prevailing trend toward limitation of ambulatory services that is characteristic of many managed care systems today.

Activities of Daily Living↗
PubMed2004

Psychotic symptoms in pediatric bipolar disorder.

BACKGROUND: There is under-recognition or misdiagnosis of pediatric bipolar disorder with psychotic features. It is of major public health importance to recognize psychosis in bipolar disorder. METHOD: Original research on phenomenological description of psychosis and external validators including family history, longitudinal course and treatment effects are systematically reviewed. Age differences, sampling, and interview methods of the studies on pediatric bipolar disorder that reported psychotic features are compared. Critical differentiating features between pediatric bipolar disorder and pediatric schizophrenia are summarized given the presence of overlapping psychotic features. RESULTS: Prevalence of psychotic features in pediatric bipolar disorder ranged from 16 to 87.5% based on age and methodological differences. The most common psychotic features are mood congruent delusions, mainly grandiose delusions. Psychotic features appear in the context of affective symptoms in pediatric bipolar disorder as opposed to schizophrenia where psychotic symptoms are independent of them. Family history of affective psychosis aggregated in probands with bipolar disorder. LIMITATIONS: There is discrepancy in clinical appraisal of what constitutes psychosis and pediatric bipolar disorder, apart from the differences in methodology and nature of the samples. CONCLUSION: Clinicians must be vigilant in identifying psychosis in pediatric bipolar disorder, especially when there is a positive family history of psychosis.

Adolescent↗