Schizophrenic delusions: a phenomenological approach.

The issue of specificity of delusions in schizophrenia is still a matter of debate. The authors analyze the delusion formation in schizophrenia from a prototypical, phenomenological point of view, focusing on the subject's experience. This perspective links delusion formation to the autistic predisposition, which is considered here as the elementary phenotypic expression of the vulnerability to schizophrenia. Autism is viewed as a defective preconceptual (i.e., before language) attunement to the world. It impedes the individual's sharing of "common sense" with others and impairs the ability to project into the future. The development of delusions is illustrated, in part, by Klaus Conrad's work on the onset of paranoid schizophrenia. Delusions are viewed as transformations of the structure of experiencing. When threatened in future ability to be, the autistic, vulnerable person looks for the clues to becoming by attributing significance to disparate elements of the environment, which become self-referential. The link established between these disparate elements is based on universal characteristics that give the schizophrenic delusion a metaphysical quality. The transitivistic experience in delusions of control and omnipotence points to a specific way of crossing the border between "mine" and "yours" (disturbances of the experiencing "I"). What strikes a clinician in these delusions is that the normally tacit link between the sense of being and the sense of acting becomes quite apparent. The authors also propose a specificity in the themes of schizophrenic delusions. Delusions acquire a schizophrenic quality when ontological (i.e., universal) elements of the discourse between the locutor and the Other dominate at the expense of the worldly elements. It is emphasized that delusional content and form are dialectically related and hardly distinguishable. The authors consider the delusion formation as a phenomenon of emergence, a situation in which a new qualitative order arises from the reorganization of essentially unchanged elements. To consider schizophrenia as an emergent, particular way of experiencing, related to the autistic defect, has important consequences for research and for treatment. A dialectic exchange is needed between prototypical models generated by phenomenological inquiry and empirical, operational validation of testable aspects of such models.

The systematic profiling of false identity documents: method validation and performance evaluation using seizures known to originate from common and different sources

False identity documents constitute a potential powerful source of forensic intelligence because they are essential elements of transnational crime and provide cover for organized crime. In previous work, a systematic profiling method using false documents' visual features has been built within a forensic intelligence model. In the current study, the comparison process and metrics lying at the heart of this profiling method are described and evaluated. This evaluation takes advantage of 347 false identity documents of four different types seized in two countries whose sources were known to be common or different (following police investigations and dismantling of counterfeit factories). Intra-source and inter-sources variations were evaluated through the computation of more than 7500 similarity scores. The profiling method could thus be validated and its performance assessed using two complementary approaches to measuring type I and type II error rates: a binary classification and the computation of likelihood ratios. Very low error rates were measured across the four document types, demonstrating the validity and robustness of the method to link documents to a common source or to differentiate them. These results pave the way for an operational implementation of a systematic profiling process integrated in a developed forensic intelligence model.

Development of a systematic computer vision-based method to analyse and compare images of false identity documents for forensic intelligence purposes-Part I: acquisition, calibration and validation issues

Following their detection and seizure by police and border guard authorities, false identity and travel documents are usually scanned, producing digital images. This research investigates the potential of these images to classify false identity documents, highlight links between documents produced by a same modus operandi or same source, and thus support forensic intelligence efforts. Inspired by previous research work about digital images of Ecstasy tablets, a systematic and complete method has been developed to acquire, collect, process and compare images of false identity documents. This first part of the article highlights the critical steps of the method and the development of a prototype that processes regions of interest extracted from images. Acquisition conditions have been fine-tuned in order to optimise reproducibility and comparability of images. Different filters and comparison metrics have been evaluated and the performance of the method has been assessed using two calibration and validation sets of documents, made up of 101 Italian driving licenses and 96 Portuguese passports seized in Switzerland, among which some were known to come from common sources. Results indicate that the use of Hue and Edge filters or their combination to extract profiles from images, and then the comparison of profiles with a Canberra distance-based metric provides the most accurate classification of documents. The method appears also to be quick, efficient and inexpensive. It can be easily operated from remote locations and shared amongst different organisations, which makes it very convenient for future operational applications. The method could serve as a first fast triage method that may help target more resource-intensive profiling methods (based on a visual, physical or chemical examination of documents for instance). Its contribution to forensic intelligence and its application to several sets of false identity documents seized by police and border guards will be developed in a forthcoming article (part II).

Validation de la version française du questionnaire I7 d'impulsivité. Influence de la personnalité, du sexe et de la religion = Validation of the french version of the eysenck's impulsiveness questionnaire (I7). Influence of personality, gender, and religion

L'objectif de cette étude est de vérifier la validité interne de la version française du questionnaire d'impulsivité d'Eysenck (I7), traduite par Dupont et al., sur un échantillon d'étudiants suisses (n = 220). Dans leur questionnaire, Eysenck et Eysenck proposent trois échelles : les deux premières évaluant deux composantes distinctes de l'impulsivité (l'Impulsivité caractérisant les individus qui agissent sans penser, sans être conscients des risques associés à leurs actions, et la Recherche d'aventure caractérisant les individus qui agissent en étant conscients, et en tenant compte des risques associés à leurs actions), et la troisième servant de « distracteur » (l'Empathie caractérisant les individus qui ont la faculté de s'identifier à l'autre). La structure à trois facteurs de l'instrument a été confirmée par notre analyse factorielle en composantes principales. La solution factorielle retenue n'explique toutefois qu'une faible proportion de la variance (21.9 %). L'homogénéité interne des échelles, mesurée à l'aide d'alphas de Cronbach, est acceptable pour l'échelle d'Impulsivité (.78) et de Recherche d'aventure (.71), mais elle est, en revanche, faible pour l'échelle d'Empathie (.62). Les échelles de l'I7 d'Eysenck entretiennent des corrélations cohérentes avec les cinq grandes dimensions de la personnalité mesurées par le NEO PI-R. L'Impulsivité est associée négativement à la dimension Conscience (r = - .32), alors que la Recherche d'aventures est associée positivement à la dimension Extraversion (r = .33). Le sexe a un impact sur les échelles Recherche d'aventure et Empathie. Les qualités métrologiques de la version française du questionnaire d'impulsivité d'Eysenck (I7) sont satisfaisantes, mais l'estimation d'autres indices de validité, comme la fidélité test-retest et la validité convergente, devrait être réalisée.

Scores to predict major bleeding risk during oral anticoagulation therapy: a prospective validation study.

BACKGROUND: Clinical scores may help physicians to better assess the individual risk/benefit of oral anticoagulant therapy. We aimed to externally validate and compare the prognostic performance of 7 clinical prediction scores for major bleeding events during oral anticoagulation therapy. METHODS: We followed 515 adult patients taking oral anticoagulants to measure the first major bleeding event over a 12-month follow-up period. The performance of each score to predict the risk of major bleeding and the physician's subjective assessment of bleeding risk were compared with the C statistic. RESULTS: The cumulative incidence of a first major bleeding event during follow-up was 6.8% (35/515). According to the 7 scoring systems, the proportions of major bleeding ranged from 3.0% to 5.7% for low-risk, 6.7% to 9.9% for intermediate-risk, and 7.4% to 15.4% for high-risk patients. The overall predictive accuracy of the scores was poor, with the C statistic ranging from 0.54 to 0.61 and not significantly different from each other (P=.84). Only the Anticoagulation and Risk Factors in Atrial Fibrillation score performed slightly better than would be expected by chance (C statistic, 0.61; 95% confidence interval, 0.52-0.70). The performance of the scores was not statistically better than physicians' subjective risk assessments (C statistic, 0.55; P=.94). CONCLUSION: The performance of 7 clinical scoring systems in predicting major bleeding events in patients receiving oral anticoagulation therapy was poor and not better than physicians' subjective assessments.

Validation of an analytical method for nitrous oxide (N2O) laughing gas by headspace gas chromatography coupled to mass spectrometry (HS-GC-MS): Forensic application to a lethal intoxication.

Drug abuse is a widespread problem affecting both teenagers and adults. Nitrous oxide is becoming increasingly popular as an inhalation drug, causing harmful neurological and hematological effects. Some gas chromatography-mass spectrometry (GC-MS) methods for nitrous oxide measurement have been previously described. The main drawbacks of these methods include a lack of sensitivity for forensic applications; including an inability to quantitatively determine the concentration of gas present. The following study provides a validated method using HS-GC-MS which incorporates hydrogen sulfide as a suitable internal standard allowing the quantification of nitrous oxide. Upon analysis, sample and internal standard have similar retention times and are eluted quickly from the molecular sieve 5Å PLOT capillary column and the Porabond Q column therefore providing rapid data collection whilst preserving well defined peaks. After validation, the method has been applied to a real case of N2O intoxication indicating concentrations in a mono-intoxication.

Validation of the IMPACT-III quality of life questionnaire in Swiss children with inflammatory bowel disease.

BACKGROUND AND AIMS: Inflammatory bowel disease (IBD) frequently manifests during childhood and adolescence. For providing and understanding a comprehensive picture of a patients' health status, health-related quality of life (HRQoL) instruments are an essential complement to clinical symptoms and functional limitations. Currently, the IMPACT-III questionnaire is one of the most frequently used disease-specific HRQoL instrument among patients with IBD. However, there is a lack of studies examining the validation and reliability of this instrument. METHODS: 146 paediatric IBD patients from the multicenter Swiss IBD paediatric cohort study database were included in the study. Medical and laboratory data were extracted from the hospital records. HRQoL data were assessed by means of standardized questionnaires filled out by the patients in a face-to-face interview. RESULTS: The original six IMPACT-III domain scales could not be replicated in the current sample. A principal component analysis with the extraction of four factor scores revealed the most robust solution. The four factors indicated good internal reliability (Cronbach's alpha=.64-.86), good concurrent validity measured by correlations with the generic KIDSCREEN-27 scales and excellent discriminant validity for the dimension of physical functioning measured by HRQoL differences for active and inactive severity groups (p<.001, d=1.04). CONCLUSIONS: This study with Swiss children with IBD indicates good validity and reliability for the IMPACT-III questionnaire. However, our findings suggest a slightly different factor structure than originally proposed. The IMPACT-III questionnaire can be recommended for its use in clinical practice. The factor structure should be further examined in other samples.

Device-specific weighted T-score for two quantitative ultrasounds: operational propositions for the management of osteoporosis for 65 years and older women in Switzerland.

The World Health Organization (WHO) criteria for the diagnosis of osteoporosis are mainly applicable for dual X-ray absorptiometry (DXA) measurements at the spine and hip levels. There is a growing demand for cheaper devices, free of ionizing radiation such as promising quantitative ultrasound (QUS). In common with many other countries, QUS measurements are increasingly used in Switzerland without adequate clinical guidelines. The T-score approach developed for DXA cannot be applied to QUS, although well-conducted prospective studies have shown that ultrasound could be a valuable predictor of fracture risk. As a consequence, an expert committee named the Swiss Quality Assurance Project (SQAP, for which the main mission is the establishment of quality assurance procedures for DXA and QUS in Switzerland) was mandated by the Swiss Association Against Osteoporosis (ASCO) in 2000 to propose operational clinical recommendations for the use of QUS in the management of osteoporosis for two QUS devices sold in Switzerland. Device-specific weighted "T-score" based on the risk of osteoporotic hip fractures as well as on the prediction of DXA osteoporosis at the hip, according to the WHO definition of osteoporosis, were calculated for the Achilles (Lunar, General Electric, Madison, Wis.) and Sahara (Hologic, Waltham, Mass.) ultrasound devices. Several studies (totaling a few thousand subjects) were used to calculate age-adjusted odd ratios (OR) and area under the receiver operating curve (AUC) for the prediction of osteoporotic fracture (taking into account a weighting score depending on the design of the study involved in the calculation). The ORs were 2.4 (1.9-3.2) and AUC 0.72 (0.66-0.77), respectively, for the Achilles, and 2.3 (1.7-3.1) and 0.75 (0.68-0.82), respectively, for the Sahara device. To translate risk estimates into thresholds for clinical application, 90% sensitivity was used to define low fracture and low osteoporosis risk, and a specificity of 80% was used to define subjects as being at high risk of fracture or having osteoporosis at the hip. From the combination of the fracture model with the hip DXA osteoporotic model, we found a T-score threshold of -1.2 and -2.5 for the stiffness (Achilles) determining, respectively, the low- and high-risk subjects. Similarly, we found a T-score at -1.0 and -2.2 for the QUI index (Sahara). Then a screening strategy combining QUS, DXA, and clinical factors for the identification of women needing treatment was proposed. The application of this approach will help to minimize the inappropriate use of QUS from which the whole field currently suffers.

Fitness to drive and cannabis: Validation of two blood THCCOOH thresholds to distinguish occasional users from heavy smokers.

Many studies based on either an experimental or an epidemiological approach, have shown that the ability to drive is impaired when the driver is under the influence of cannabis. Baseline performances of heavy users remain impaired even after several weeks of abstinence. Symptoms of cannabis abuse and dependence are generally considered incompatible with safe driving. Recently, it has been shown that traffic safety can be increased by reporting the long-term unfit drivers to the driver licensing authorities and referring the cases for further medical assessment. Evaluation of the frequency of cannabis use is a prerequisite for a reliable medical assessment of the fitness to drive. In a previous paper we advocated the use of two thresholds based on 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH) concentration in whole blood to help to distinguish occasional cannabis users (≤3μg/L) from heavy regular smokers (≥40μg/L). These criteria were established on the basis of results obtained in a controlled cannabis smoking study with placebo, carried out with two groups of young male volunteers; the first group was characterized by a heavy use (≥10 joints/month) while the second group was made up of occasional users smoking at most 1 joint/week. However, to date, these cutoffs have not been adequately assessed under real conditions. Their validity can now be evaluated and confirmed with 146 traffic offenders' real cases in which the whole blood cannabinoid concentrations and the frequency of cannabis use are known. The two thresholds were not challenged by the presence of ethanol (40% of cases) and of other therapeutic and illegal drugs (24%). Thus, we propose the following procedure that can be very useful in the Swiss context but also in other countries with similar traffic policies: if the whole blood THCCOOH concentration is higher than 40μg/L, traffic offenders must be directed first and foremost toward medical assessment of their fitness to drive. This evaluation is not recommended if the THCCOOH concentration is lower than 3μg/L and if the self-rated frequency of cannabis use is less than 1 time/week. A THCCOOH level between these two thresholds cannot be reliably interpreted. In such a case, further medical assessment and follow-up of the fitness to drive are also suggested, but with lower priority.

Validation and long-term evaluation of a modified on-line chiral analytical method for therapeutic drug monitoring of (R,S)-methadone in clinical samples.

Matrix effects, which represent an important issue in liquid chromatography coupled to mass spectrometry or tandem mass spectrometry detection, should be closely assessed during method development. In the case of quantitative analysis, the use of stable isotope-labelled internal standard with physico-chemical properties and ionization behaviour similar to the analyte is recommended. In this paper, an example of the choice of a co-eluting deuterated internal standard to compensate for short-term and long-term matrix effect in the case of chiral (R,S)-methadone plasma quantification is reported. The method was fully validated over a concentration range of 5-800 ng/mL for each methadone enantiomer with satisfactory relative bias (-1.0 to 1.0%), repeatability (0.9-4.9%) and intermediate precision (1.4-12.0%). From the results obtained during validation, a control chart process during 52 series of routine analysis was established using both intermediate precision standard deviation and FDA acceptance criteria. The results of routine quality control samples were generally included in the +/-15% variability around the target value and mainly in the two standard deviation interval illustrating the long-term stability of the method. The intermediate precision variability estimated in method validation was found to be coherent with the routine use of the method. During this period, 257 trough concentration and 54 peak concentration plasma samples of patients undergoing (R,S)-methadone treatment were successfully analysed for routine therapeutic drug monitoring.

Prospective validation of the Pulmonary Embolism Severity Index. A clinical prognostic model for pulmonary embolism

Practice guidelines recommend outpatient care for selected patients with non-massive pulmonary embolism (PE), but fail to specify how these low-risk patients should be identified. Using data from U.S. patients, we previously derived the Pulmonary Embolism Severity Index (PESI), a prediction rule that risk stratifies patients with PE. We sought to validate the PESI in a European patient cohort. We prospectively validated the PESI in patients with PE diagnosed at six emergency departments in three European countries. We used baseline data for the rule's 11 prognostic variables to stratify patients into five risk classes (I-V) of increasing probability of mortality. The outcome was overall mortality at 90 days after presentation. To assess the accuracy of the PESI to predict mortality, we estimated the sensitivity, specificity, and predictive values for low- (risk classes I/II) versus higher-risk patients (risk classes III-V), and the discriminatory power using the area under the receiver operating characteristic (ROC) curve. Among 357 patients with PE, overall mortality was 5.9%, ranging from 0% in class I to 17.9% in class V. The 186 (52%) low-risk patients had an overall mortality of 1.1% (95% confidence interval [CI]: 0.1-3.8%) compared to 11.1% (95% CI: 6.8-16.8%) in the 171 (48%) higher-risk patients. The PESI had a high sensitivity (91%, 95% CI: 71-97%) and a negative predictive value (99%, 95% CI: 96-100%) for predicting mortality. The area under the ROC curve was 0.78 (95% CI: 0.70-0.86). The PESI reliably identifies patients with PE who are at low risk of death and who are potential candidates for outpatient care. The PESI may help physicians make more rational decisions about hospitalization for patients with PE.