Experienced Investigators (experience + investigator)

Distribution by Scientific Domains


Selected Abstracts


Tool to classify stool consistency: Content validity and use by persons of diverse cultures

NURSING & HEALTH SCIENCES, Issue 2 2003
Donna Zimmaro Bliss PhD
Abstract Developing and testing the quality of a research instrument, including its ability to be used by culturally diverse persons, is an important methodological objective. The present study determined the content validity and feasibility of culturally diverse persons to use an instrument to classify stool consistency that has been employed in research on fecal incontinence. Five multidisciplinary clinicians experienced in assessing stool consistency determined the tool to possess content validity. Twenty-four foreign nationals of diverse cultures who spoke English as a second language (ESL) classified the consistency of nine stools using word only or word plus diagram descriptions. The agreement of the ratings of the participants were compared with the those of an experienced investigator. There was no significant difference between the ratings of participants using either type of description. There was good agreement between the classifications of the participants and those of the investigator. The findings of this study contribute to the quality of our instrument and support its use by culturally diverse persons. [source]


Diagnostic performance of the variant lymphocyte flag of the Abbott Cell-Dyn 4000 haematology analyser

INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2004
J. J. M. L. Hoffmann
Summary Background: In addition to differential cell counts, modern haematology analysers generate suspect flags if abnormal cells are detected. Reports on validation of suspect flags are scarce. We have routine experience with the Abbott Cell-Dyn 4000 analyser for over 5 years and have previously demonstrated the utility of the blast flag. Here we report a similar study on the performance of the analyser's Variant Lymphocyte (VL) flag. Aim of the study: Evaluation of the diagnostic performance of the Cell-Dyn 4000 VL flag, as compared with lymphocyte morphology in blood smears. In addition, we investigated the usefulness of the numerical VL flag confidence index as provided by the analyser. Materials and methods: All samples generating a VL flag were reviewed over a 5-month period. We also reviewed smears from patients with known lymphoid disorders, even if the analyser did not flag the sample. Two experienced investigators assessed lymphocyte morphology independently. Results: In total, 187 samples were included in the study, of which 183 had a VL flag and four had not. Of the 183 flagged samples, 83 appeared to have abnormal lymphocyte morphology and 100, normal lymphocyte morphology. The sensitivity of the VL flag for detecting abnormal lymphocytes was 0.95 and the positive predictive value was 0.44. Using ROC analysis of the VL flag confidence index, the area under the ROC curve was 0.58 (95% confidence interval 0.50,0.65). Conclusions: The Cell-Dyn VL flag has reasonable sensitivity but a high false-positive rate. In addition, its performance is insufficient for detecting clinically relevant abnormal lymphocytes. As the VL flag appeared to rely mainly on numerical criteria, it has no added value over numerical criteria defined by the laboratory. [source]


The allergen bronchoprovocation model: an important tool for the investigation of new asthma anti-inflammatory therapies

ALLERGY, Issue 10 2007
L.-P. Boulet
Allergen bronchoprovocation tests have been used for more than two decades in the investigation of respiratory allergic diseases such as asthma and rhinitis. These bronchial challenges are now well standardized and can offer key information on the therapeutic potential of new agents and on their anti-inflammatory effects on the airways. Both standard and low-dose allergen provocations are safe when performed by experienced investigators and do not lead to persistent worsening of asthma or change in airway function. The evaluation of new therapeutic agents by these methods can also provide important information on the mechanisms of development and persistence of airway diseases. [source]


Conceptual Models of Health Behavior: Research in the Emergency Care Settings

ACADEMIC EMERGENCY MEDICINE, Issue 11 2009
Edwin D. Boudreaux PhD
Abstract This article provides recommendations for incorporating conceptual models of health behavior change into research conducted in emergency care settings. The authors drafted a set of preliminary recommendations, which were reviewed and discussed by a panel of experienced investigators attending the 2009 Academic Emergency Medicine consensus conference. The original recommendations were expanded and refined based on their input. This article reports the final recommendations. Three recommendations were made: 1) research conducted in emergency care settings that focuses on health behaviors should be grounded in formal conceptual models, 2) investigators should clearly operationalize their outcomes of interest, and 3) expected relations between theoretical constructs and outcomes should be made explicit prior to initiating a study. A priori hypothesis generation grounded in conceptual models of health behavior, followed by empirical validation of these hypotheses, is needed to improve preventive and public health,related interventions in emergency care settings. [source]