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At least 1,333 records · Page 74Linked to original sources
PubMed2003

[Validity of the International Prognostic Index in non-Hodgkin's lymphomas of varying grades of malignancy].

OBJECTIVE: The "International Prognostic Index" (IPI) has been published for patients with histological intermediate grade malignancy non-Hodgkin's lymphoma (NHL) according to the Working Formulation (WF). The IPI is based on pre-treatment clinical characteristics: age, performance status, Ann Arbor stage, extranodal sites, serum lactate-dehydrogenase concentration. We investigated whether the IPI also had prognostic value for NHL patients with a low grade malignancy or high grade malignancy according to the WF. PATIENTS AND METHODS: Our series included 192 patients with NHL, diagnosed in a single institution between 1986 and 1998. In each patient the relationship among IPI, response to therapy and survival was investigated. RESULTS: The IPI turned out to be of prognostic value for response rate and survival in our unselected cohort of patients, as well. In each of the three WF classes separately (low, intermediate, high grade malignancy), the four IPI classes showed going from low to high risk substantially decreasing response rates and survival percentages. CONCLUSIONS: The IPI is confirmed as an important tool for prognostic evaluation of NHL patients: an integration of IPI, histological grading and serum beta 2-microglobulin concentration is supported.

Adult↗
PubMed2005

Screening for and validated quantification of phenethylamine-type designer drugs and mescaline in human blood plasma by gas chromatography/mass spectrometry.

In recent years, several newer designer drugs of the so-called 2C series such as 2C-D, 2C-E, 2C-P, 2C-B, 2C-I, 2C-T-2, and 2C-T-7 have entered the illicit drug market as recreational drugs. Some fatal intoxications involving 2C-T-7 have been reported. Only scarce data have been published about analyses of these substances in human blood and/or plasma. This paper describes a method for screening and simultaneous quantification of the above-mentioned compounds and their analog mescaline in human blood plasma. The analytes were analyzed by gas chromatography/mass spectrometry in the selected-ion monitoring mode, after mixed-mode solid-phase extraction (HCX) and derivatization with heptafluorobutyric anhydride. The method was fully validated according to international guidelines. Validation data for 2C-T-2 and 2C-T-7 were unacceptable. For all other analytes, the method was linear from 5 to 500 microg/L and the data for accuracy (bias) and precision (coefficient of variation) were within the acceptance limits of +/-15% and <15%, respectively (within +/-20% and <20% near the limit of quantification of 5 microg/L).

Designer Drugs↗
PubMed2004

Internal consistency, convergent validity and reliability of a brief questionnaire on disordered eating (DEQ).

Clinical interviews are considered the gold standard for the evaluation of the specific psychopathology associated with eating disorders. However, there are situations in which brief but valid and reliable self-report questionnaires can be helpful. For this reason, we have developed a new questionnaire, called the DEQ (Disordered Eating Questionnaire), brief enough to be used in epidemiological screenings, that evaluates the frequency and intensity of disordered eating attitudes and behaviours within a time frame of three months and addresses face valid questions to the general population. The aim of this study was to evaluate the dimensionality, reliability and convergent validity of this questionnaire. The DEQ was filled in by Italian secondary school girls and boys, together with the Contour Drawing Rating Scale (CDRS) and with the Eating Attitudes Test (EAT-26). The results showed a single component that explain a portion of variance of around 36%. The reliability of the scale is highly satisfactory. The scale is also valid, since scores on the DEQ scale are significantly and highly correlated with body dissatisfaction, measured by the CDRS, with body mass inex (BMI) and with all the subscales of the EAT-26. As expected, there were gender differences, given that DEQ scores were higher in females than in males.

Adolescent↗
PubMed1993

Interlaboratory variations of fluoroquinolone susceptibility testing. An international study to validate the quality of microbiology results reported during the fleroxacin clinical trials.

Fleroxacin, a newer fluoroquinolone, has been investigated extensively in worldwide clinical trials by laboratories using a variety of in vitro susceptibility testing methods. These methods differ in their technical details, leading to applied interpretive criteria that can also differ from nation to nation and from method to method. This retrospective three-phase investigation was designed to assess the disk diffusion and minimum inhibitory concentration (MIC) result variations produced by European laboratories participating in fleroxacin clinical trials as compared with the results of a reference laboratory performing National Committee for Clinical Laboratory Standards (NCCLS) tests. In "phase I," 105 clinical trial strains (1988-1989) from six European investigators were processed by the reference laboratory. In comparison of participant and reference laboratory zone diameters, absolute qualitative agreement was 88.7% for the approved NCCLS interpretive criteria and 94.8% for the criteria used in the fleroxacin urinary tract infection clinical trials. Only three false-susceptible results (3.1%) were reported by the investigators. In the remaining phases of this study (unknown challenge strains and contemporary clinical isolates), the investigator laboratory zone diameters and MICs were within limits of acceptable test variation, that is, +/- 4 mm by disk diffusion and +/- 1 log2 dilution step by the MIC method. For laboratories using the German (DIN) and French (SFM) methods, however, a trend toward larger zones was observed. The greatest variation between participant and NCCLS results was produced when fastidious isolates such as Haemophilus influenzae (significantly smaller zone diameters) were tested. In general, the European fleroxacin clinical trial laboratory results (organism identification and susceptibility tests) could be considered comparable to data produced with NCCLS reference methods, indicating that clinical trial results from wider sources could be used for drug registry by the US Food and Drug Administration (FDA) or by other national agencies.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteria↗
PubMed2006

QSPR-based prediction of gas/particle partitioning of polychlorinated biphenyls in the atmosphere.

By reviewing the existing models for describing gas/particle partitioning of semi-volatile organic compounds in the atmosphere, it was assumed that gas/particle partition coefficient, expressed as Kp, may be predicted using molecular descriptors. Overall 14 molecular descriptors of each compound calculated using semi-empirical method parametric model 3 (PM3) were tested against logKp of selected PCBs to determine the best ones governing partitioning. Eight descriptors molecular weight (Mw), molecular volume (Mv), total energy (TE), electronic energy (EE), squared atom electron densities on carbon, hydrogen and chlorine atoms in a given molecule (Summation qC2, Summation qCl2, Summation qH2) and average molecular polarizability (alpha m) were found to be highly correlated with logKp compared to other molecular descriptors. Using Partial Least-Squares Regression method (PLS), two-, three- and four-descriptor QSPR models with high fitting characters were successfully developed and their robustness and predictive power were further validated by internal cross-validation and external test. Finally, the gas/particle partition coefficients of all 209 PCBs were predicted for the first time.

Air Pollutants↗
PubMed1997

Diagnosis of primary headache disorders. Validity of the International Headache Society criteria in clinical practice.

The classification and diagnostic criteria of the primary headaches--migraine, tension-type headache, and cluster headache--have been reviewed. Additional features of these conditions may enhance diagnostic accuracy. Modification of the classification and diagnostic criteria will take place as epidemiologic and pathophysiologic data continue to develop.

Cluster Headache↗
PubMed2004

Progressing toward the reduction, refinement and replacement of laboratory animal procedures: thoughts on some encounters with Dr Iain Purchase.

A variety of encounters with Dr Iain Purchase over the last 25 years are reviewed in relation to their significance in terms of progress toward the reduction, refinement and replacement of animal procedures in toxicology and toxicity testing. Included are the work of the first FRAME Toxicity Committee and the FRAME International Alternatives Validation Scheme, the International Conferences on Practical In Vitro Toxicology and the foundation of Toxicology in Vitro, the work of an Institute of Medical Ethics working party on issues raised by animal experimentation and alternative approaches, the need for in vitro assays for chemical carcinogenesis based on the transformation of human cells, the problem presented by the human hazard potential of thousands of chemicals already in use before modern regulations for the registration of new chemicals came into force, and the importance of testing strategies with a focus on the integrated use of non-animal computer-based and in vitro test systems.

Animal Experimentation↗
PubMedDate not supplied

The Verbal Behavior Assessment Scale (VerBAS): construct validity, reliability, and internal consistency.

A questionnaire, the Verbal Behavior Assessment Scale, was developed to assess the communicative functions of individuals with developmental disabilities and severe mental handicap. To assess its psychometric characteristics, the questionnaire, comprising 15 items, was administered to pairs of caregivers of 115 participants. Exploratory factor analysis, involving 11 more participants, revealed satisfactory evidence concerning the distinction of three different communicative functions with the present sample. The questionnaire had good levels of interrater reliability and internal consistency.

Adolescent↗
PubMed1999

Threats to validity in the longitudinal study of psychological effects: the case of short stature.

In all studies of health-related problems and their effects on well-being, research design issues threaten to compromise the validity of findings. This is particularly so in a longitudinal study, essentially stemming from the tension between maintaining participant compliance and retaining investigator objectivity. Such a tension may be exacerbated where measures of dependent variables such as self-esteem are used alongside the collection of physical data which is essential to the study, as in research into the psychological effects of short stature on children and young people. In this paper one particular project, the Wessex Growth Study, is used to illustrate the common threats to validity, both internal and external, of such research, and to consider future improvements in design. The Wessex Growth Study, set up in 1986, was designed to overcome some of the methodological problems found in earlier research with short stature children. It is following the growth and psychological development through their school years of a cohort of short children (below third centile for height when first identified) and case-matched controls (10th-90th centiles) recruited at school entry (ages 5/6). Findings have generally found only small differences between short and average height children. Though these results so far have mainly been presented cross-sectionally, the young people involved are followed up at 6-monthly intervals for height and other data to be collected, and thus to some extent the study also has the advantages and problems of a longitudinal research design. Using Campbell and Stanley's criteria this article makes clear the strain on both internal and external validity in the study, but argues that these problems are to some extent inherent in all longitudinal psychological research, and are outweighed in the present research by the collection of data on short stature which would not otherwise be available. Future data collection within the study will introduce further improvements in design.

Adolescent↗
PubMed1994

Validation of the International Study Group criteria for Behçet's disease.

The International Study Group (ISG) for Behçet's disease proposed new international criteria for Behçet's disease in 1990. The aim of this study was to assess the performance of these criteria in new patient groups. Sensitivity was determined in 300 patients with Behçet's disease from seven countries, and specificity in a group of 62 control patients from China. The ISG criteria performed well compared to the other criteria sets in current use.

Behcet Syndrome↗
PubMed2000

Validation of the International Classification of Diseases 10th Edition-based Injury Severity Score (ICISS).

OBJECTIVE: To compare the predictive power of International Classification of Diseases 10th Edition (ICD-10)-based International Classification of Diseases 9th Edition-based Injury Severity Score (ICISS) with Trauma and Injury Severity Score (TRISS) and ICD-9CM-based ICISS in the injury severity measure. METHODS: ICD-10 version of survival risk ratios was derived from 47,750 trauma patients from 35 emergency centers for 1 year. The predictive power of TRISS, the ICD-9CM-based ICISS and ICD-10-based ICISS were compared in a group of 367 severely injured patients admitted to two university hospitals. The predictive power was compared by using the measures of discrimination (disparity, sensitivity, specificity, misclassification rates, and receiver operating characteristic curve analysis) and calibration (Hosmer-Lemeshow goodness-of-fit statistics), all calculated by logistic regression procedure. RESULTS: ICD-10-based ICISS showed a lower performance than TRISS and ICD-9CM-based ICISS. When age and Revised Trauma Score were incorporated into the survival probability model, however, ICD-10-based ICISS full model showed a similar predictive power compared with TRISS and ICD-9CM-based ICISS full model. ICD-10-based ICISS had some disadvantages in predicting outcomes among patients with intracranial injuries. However, such weakness was largely compensated by incorporating age and Revised Trauma Score in the model. CONCLUSION: The ICISS methodology can be extended to ICD-10 horizon as a standard injury severity measure in the place of TRISS, especially when age and Revised Trauma Score were incorporated in the model. For patients with intracranial injuries, the predictive power of ICD-10-based ICISS was relatively low because of differences in the classifying system between ICD-10 and ICD-9CM.

Adult↗
PubMed2003

Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study.

BACKGROUND: In the assessment of severity in community acquired pneumonia (CAP), the modified British Thoracic Society (mBTS) rule identifies patients with severe pneumonia but not patients who might be suitable for home management. A multicentre study was conducted to derive and validate a practical severity assessment model for stratifying adults hospitalised with CAP into different management groups. METHODS: Data from three prospective studies of CAP conducted in the UK, New Zealand, and the Netherlands were combined. A derivation cohort comprising 80% of the data was used to develop the model. Prognostic variables were identified using multiple logistic regression with 30 day mortality as the outcome measure. The final model was tested against the validation cohort. RESULTS: 1068 patients were studied (mean age 64 years, 51.5% male, 30 day mortality 9%). Age >/=65 years (OR 3.5, 95% CI 1.6 to 8.0) and albumin <30 g/dl (OR 4.7, 95% CI 2.5 to 8.7) were independently associated with mortality over and above the mBTS rule (OR 5.2, 95% CI 2.7 to 10). A six point score, one point for each of Confusion, Urea >7 mmol/l, Respiratory rate >/=30/min, low systolic(<90 mm Hg) or diastolic (</=60 mm Hg) Blood pressure), age >/=65 years (CURB-65 score) based on information available at initial hospital assessment, enabled patients to be stratified according to increasing risk of mortality: score 0, 0.7%; score 1, 3.2%; score 2, 3%; score 3, 17%; score 4, 41.5% and score 5, 57%. The validation cohort confirmed a similar pattern. CONCLUSIONS: A simple six point score based on confusion, urea, respiratory rate, blood pressure, and age can be used to stratify patients with CAP into different management groups.

Adult↗