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Cross-validation Study (cross-validation + study)
Selected AbstractsThe construct validity of the client questionnaire of the Wisconsin Quality of Life Index , a cross-validation studyINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 3 2003Jean Caron Abstract The Wisconsin Quality of Life Index (W-QLI, Becker, Diamond and Sainfort, 1993) consists of eight scales: satisfaction with life domains, occupational activities, symptoms, physical health, social relations/support, finances, psychological wellbeing, and activities of daily living. The W-QLI has been modified to fit the characteristics of the Canadian population, the universal Canadian health system, and community and social services in Canada and the modified form was named CaW-QLI (Diaz, Mercier, Hachey, Caron, and Boyer, 1999). This study will verify the empirical basis of these theoretical dimensions by applying a cross-validation procedure on two samples, most of whose subjects have a serious mental illness. Confirmatory factor analyses and exploratory factor analyses using the principal component extraction technique with varimax rotation were applied. With the exception of the occupational activities domain, the remaining scales were correctly identified by the factor analyses on each sample. The occupational activities scale should be developed by additional items for representing this scale, which is too brief, and two other items should be revised in order to improve the quality of the instrument. Copyright © 2003 Whurr Publishers Ltd. [source] Development and Validation of a Geriatric Knowledge Test for Medical StudentsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2004Ming Lee PhD Objectives: To assesses the reliability and validity of a geriatrics knowledge test designed for medical students. Design: Cross-sectional studies. Setting: An academic medical center. Participants: A total of 343 (86% of those sampled) medical students participated in the initial study, including 137 (76%) first-year, 163 (96%) third-year, and 43 (86% of those sampled) fourth-year students in the 2000,2001 academic year. To cross-validate the instrument, another 165 (92%) third-year and 137 (76%) first-year students participated in the study in the 2001,2002 academic year. Measurements: An 18-item geriatrics knowledge test was developed. The items were selected from a pool of 23 items. An established instrument assessing the clinical skills of medical students was included in the validation procedure. Results: The instrument demonstrated good reliability (Cronbach ,=0.80) and known-groups and concurrent validity. Geriatrics knowledge scores increased progressively with the higher level of medical training (mean percentage correct=31.3, 65.3, and 66.5 for the first-year, third-year, and fourth-year classes, respectively, P<.001). A significant (P<.01) relationship was found between the third-year students' geriatrics knowledge and their clinical skills. Similar results, except the relationship between knowledge and clinical skills, were found in the cross-validation study, supporting the reliability and known-groups validity of the test. Conclusion: The 18-item geriatrics knowledge test demonstrated sound reliability and validity. The average scores of the student groups indicated substantial room for growth. The relationship between geriatrics knowledge and overall clinical skills needs further investigation. [source] Predictors of quality of life in old age: A cross-validation study,RESEARCH IN NURSING & HEALTH, Issue 2 2007Gail Low Abstract A replication study was undertaken to validate a model of quality of life (QOL) generated in an earlier study on a random sample of 202 older adults. Pathways found to be significant were retested using QOL data from a convenience sample of 420 older adults. Using path analysis, we found that financial resources, health, and meaning in life directly and positively influenced QOL. Health, emotional support, and the physical environment indirectly affected QOL through purpose in life. All but one pathway were replicated, explaining 50.5% of the variance in QOL. Further explorations of the influence of spirituality, emotionally close ties, and opportunities for active engagement on QOL in older age are warranted. © 2007 Wiley Periodicals, Inc. Res Nurs Health 30: 141,150, 2007 [source] Influence of blood sampling on protein profiling and pattern analysis using matrix-assisted laser desorption/ionisation mass spectrometryBJU INTERNATIONAL, Issue 3 2007Alexandre E. Pelzer OBJECTIVE To describe the influence of blood sampling/sampling tubes on mass spectrometric and clustering results, and on clinical blood variables, in blood samples collected from healthy volunteers and patients with prostate cancer. PATIENTS, SUBJECTS AND METHODS Two venous blood samples were taken from 12 healthy volunteers and 12 patients with localized prostate cancer. Two blood samples were taken from each participant using two different venepuncture systems (group A and group B). The Kolmogorov,Smirnov test was used to identify the peaks distinguishing the different groups. In a 10-fold cross-validation study, decision trees for identifying discriminatory peaks that separate the benign from the malignant were constructed. RESULTS The decision tree separated samples measured by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) from healthy volunteers from those of patients with prostate cancer, with a sensitivity of 93.6% and a specificity of 91.6%. Of special interest is that one peak at 6941 m/z was produced during blood sample preparation and had a very powerful influence on the results of the classification. CONCLUSION The results clearly showed that blood-sampling systems have a great influence on the recorded MALDI MS traces, and thus can markedly influence and confound the results of the MS analysis, whereas clinical variables might remain unchanged. MS profiling is a promising method of marker discovery, but as it could be shown well-designed studies are critical to allow proper interpretation for the identification of key variables as well as for the clinical use. [source] | ||||||||||