Comparing Groups (comparing + groups)

Distribution by Scientific Domains


Selected Abstracts


Are cognitive differences between immigrant and majority groups diminishing?

EUROPEAN JOURNAL OF PERSONALITY, Issue 5 2004
Jan te Nijenhuis
A review is given of scores on various cognitive measures, comparing groups of ethnic Dutch and non-Western immigrants using a large number of datasets. The research shows that there are large group differences in school results, work proficiency, and g for Turks, Moroccans, Surinamese, Netherlands Antilleans, and Indonesians from the Moluccans compared with ethnic Dutch. However, South-East Asians score higher, and persons with one immigrant and one ethnic Dutch parent score only slightly below the mean of the Dutch. When comparing first-generation disadvantaged immigrant groups with later generations the data show substantial improvements for g, a remarkable stability of educational differences for younger children, and a clear improvement in educational achievement at the end of primary school. Indirect data on intergenerational improvements in work proficiency appear suggestive of a trend of closing gaps. Some of the data reflect higher cognitive capacities over time, and this enhances integration of immigrants into Dutch society. Causes of group differences and improvements in mean level of g are discussed. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Independence and nonindependence: A simple method for comparing groups using multiple measures and the binomial test

EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2005
Craig McGarty
Existing methods for conducting analyses of small group data are either highly complicated or yield low power. Both of these limitations provide disincentives for the progress of research in this field. An alternative method modelled on the sign (binomial) test which involves comparing the differences of distributions based on multiple observations of each of the groups is presented. The calculations involved in the procedure are extremely simple. It is suggested that because the method enhances researchers' ability to make sound statistical inferences easily this should stimulate research on group-level processes and on social interaction more generally. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Tissue response to polyglycolide, polydioxanone, polylevolactide, and metallic pins in cancellous bone: An experimental study on rabbits

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2006
Harri Pihlajamäki
Abstract The purpose of this study was to investigate, qualitatively and histoquantitatively, the tissue response of rabbit femur cancellous bone to polyglycolide (PGA), polydioxanone (PDS), polylevolactide (PLLA), and stainless steel pins under identical conditions. Eighty knees in 50 rabbits were operated on by inserting bioabsorbable pins (PGA, PDS, or PLLA) together with metallic Kirschner wire in 60, and two metallic Kirschner wires alone in 20 knees, while 20 knees served as intact controls. Follow-up times were 3, 6, 12, 24, and 52 weeks. Cancellous bone tissue response to implants was studied using histological, histomorphometrical, microradiographical, and oxytetracycline fluorescence methods. Residual fragments of PGA and PDS were seen at 24 weeks. Complete degradation of these polymers had taken place before 52 weeks. No signs of degradation of the PLLA pins were observed within the entire follow-up period. The osteoid formation surfaces at tissue implant-interface were statistically larger in all test groups as compared to intact controls. The number of macrophages at tissue implant-interfaces increased in all bioabsorbable implant specimens until 6 weeks, and with PGA until 12 weeks. No differences in the osseous response emerged when comparing groups of bioabsorbable implants with each other or with stainless steel group. Bioabsorbable pins and metallic Kirschner wires evoked an osteoconductive response in the cancellous bone surrounding implant, but the response intensity between implants displayed no differences. This suggests a simple, nonspecific walling-off new-bone front type of response. Consequently, the polymers possessed no specific osteostimulatory or osteoinhibitory properties. Within the follow-up, no significant differences in biocompatibility between the implants appeared, and no frank inflammatory foreign-body reactions occurred. The small-volume pins obviously did not exceed the local tissue tolerance and clearing capacity of the bone. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:1597,1606, 2006 [source]


Early cytomegalovirus infection and the long-term outcome of biliary atresia

ACTA PAEDIATRICA, Issue 10 2009
Björn Fischler
Abstract Aim:, To study the impact of ongoing cytomegalovirus (CMV) infection at presentation of biliary atresia (BA) on the long-term outcome after Kasai procedure. Methods:, Twenty-eight patients with BA born 1988,1997 were included and followed-up until 2007. Eleven patients (group A) had ongoing CMV infection at presentation and were compared to the remaining 17 patients (group B). Median age at Kasai procedure was 75 days in group A and 70 days in group B (p = 0.12). Results:, Including all patients, survival with native liver was 50% and 36% at 4 and 10 years of follow-up respectively. At the end of follow-up, it was 25% and overall survival was 68%. When comparing groups A and B, neither difference in survival with native liver (p = 0.67, log-rank test) nor in survival after liver transplantation was detected. Conclusion:, Survival with native liver after Kasai procedure is comparable to that of other centres. CMV positive patients may present with a later onset, alternatively the detection of CMV infection could delay the referral of BA patients. No significant differences in long-term outcome were detected with regard to early CMV infection. [source]


Validity of two oral health-related quality of life measures

COMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY, Issue 2 2003
Peter G. Robinson
Abstract , Objectives: To assess the validity of the Oral Impacts on Daily Performance (OIDP) and the short form of the Oral Health Impact Profile (OHIP 14) in the UK. Setting: Primary care department at a UK dental hospital. Sample: Consecutive patients. Method: Cross-sectional comparison of impacts using OIDP and OHIP 14 against clinical findings, Global Oral Health Ratings and pain. Results: A total of 179 patients participated (83.2% response rate). OIDP had weak face validity because it contained contingency questions. Both instruments were developed from the same theoretical model and appeared to have reasonable content validity. In regression analyses, the number of impacts detected by each measure and the total score using OHIP 14 were related to the presence of oral disease and inversely related to age. No suitable transformation could be found to allow regression analysis of OIDP total scores. OHIP 14 correlated more closely with Global Oral Health Ratings but both measures correlated similarly to the experience of pain (0.43 < r < 0.47). The correlation between OHIP and OIDP scores was +0.78. The use of a simple additive method for calculating the total OHIP 14 score did not compromise its validity. Conclusion: Both instruments have some validity as measures of Oral Health-Related Quality of Life (OHRQoL) among dental hospital patients. The superior face, criterion and convergent validity and greater amenability to analysis of OHIP 14 render it more suitable for questionnaire-based research and for comparing groups. The additive method may be used to calculate the total score for OHIP 14. [source]