Assessing Mediation in Dyadic Data Using the Actor-Partner Interdependence Model

The assessment of mediation in dyadic data is an important issue if researchers are to test process models. Using an extended version of the actor–partner interdependence model the estimation and testing of mediation is complex, especially when dyad members are distinguishable (e.g., heterosexual couples). We show how the complexity of the model can be reduced by assuming specific dyadic patterns. Using structural equation modeling, we demonstrate how specific mediating effects and contrasts among effects can be tested by phantom models that permit point and bootstrap interval estimates. We illustrate the assessment of mediation and the strategies to simplify the model using data from heterosexual couples.     

Individuelle und strukturelle Faktoren der Mitgliederbindung im Sportverein

This article analyses the conditions influencing the commitment of members of sports clubs. It focuses not only on individual characteristics of members, but also on the corresponding structural conditions of sports clubs related to the individual decision to quit or continue their membership. The influences of both the individual and context levels on the commitment of members are estimated in different multi-level models. Results of these multi-level analyses indicate that commitment of members is not just an outcome of individual characteristics such as strong commitment to the club, positively perceived communication and cooperation, satisfaction with sports clubs? offers, or voluntary engagement. It is also influenced by club-specific structural conditions: commitment is more probable in rural sports clubs, and clubs who explicitly support sociability, whereas success-oriented sporting goals in clubs have a destabilizing effect.     

Maximal Reliability and Composite Reliability: Examining Their Difference for Multicomponent Measuring Instruments Using Latent Variable Modeling

A latent variable modeling method for examining the difference between maximal reliability and composite reliability for homogenous multicomponent measuring instruments is outlined. The procedure allows point and interval estimation of the discrepancy between the reliability coefficients associated with the optimal linear combination and with the popular unit-weighted sum of the scale components. The approach permits a researcher to make an informed choice if needed between the maximal reliability and composite reliability coefficients and concepts in an empirical setting as indexes of quality of measurement with an instrument under consideration. The discussed method is illustrated using numerical data.     

Mothers roles in traditional and modern korean families: The consequences for parental practices and adolescent socialization

This paper examines Korean mothers’ roles in the socialization of their adolescent children. First, the issue is analyzed through a historical approach that takes into account the Confucian background of Korean family life. Secondly, we consider concepts and results from recent studies on mothers’ attitudes, parenting styles, and adolescent socialization. Some of the arguments and data are particularly relevant to middle class mothers. We point out that the Confucian influence remains strong in modern South Korea while at the same time mothers responsibilities in parenting and socialization have increased. As a consequence, the relationship between mothers and their adolescent children has become more complex, intense, and unstable. We conclude that the balancing of autonomy and relatedness is the most important developmental task facing mothers and their children. Research underlying this article was supported through a grant from Mokpo National University (2000).     

The sensitivity and precision of search terms in Phases I, II and III of the Cochrane Highly Sensitive Search Strategy for identifying reports of randomized trials in medline in a specific area of health care--HIV/AIDS prevention and treatment interventions

OBJECTIVES: To detect term(s) in the Cochrane Highly Sensitive Search Strategy (HSSS) that retain high sensitivity but improve precision in retrieving reports of trials in the PubMed version of medline. METHODS: Individual terms from the PubMed version of the HSSS were added, term by term, to an African HIV/AIDS strategy to identify reports of trials in medline using PubMed. The titles and abstracts of the records retrieved were read by two handsearchers and checked by a clinical epidemiologist. The sensitivity and precision of each term in the three phases of the HSSS were calculated. RESULTS: Of 7,719 records retrieved, 285 were identified as reports of trials [204 randomized (RCTs); 81 possibly randomized or quasi-randomized (CCTs)]. Phase III had the highest sensitivity (92%). Overall, precision was very low (3.7%). One term, 'random*[tw]', retrieved all RCTs found by our search and improved precision to 29%. The least sensitive terms, yielding no records, were '(doubl* AND mask*)[tw]' and terms containing 'trebl*' or 'tripl*', except for '(tripl* AND blind*)[tw]'. The highest precision per term was for 'Double-blind Method [MeSH]' (76%). CONCLUSIONS: To retrieve all RCTs and CCTs found by our search, seven terms are needed but precision remains low (4.3%). Developments in the methods of search strategy design may help to improve precision while retaining high levels of sensitivity by identifying term(s) which occur frequently in relevant records and are the most efficient at discriminating between different study designs.     

Developing a geographic search filter to identify randomised controlled trials in Africa: finding the optimal balance between sensitivity and precision

Background: Research on identifying trials using geographic filters is limited. Objectives:  To test the sensitivity and precision of a filter to identify African randomised controlled trials (RCTs). Methods: We searched medline and embase for RCTs published in 2004 using a Cochrane filter for RCTs. The search was limited to HIV/AIDS but irrespective of location. Two investigators independently identified African RCTs from the retrieved records forming a reference set. We then repeated the search using an African geographic filter comprising country and regional terms forming the filter set. We compared the sensitivity and precision of the sets. Results: The medline reference set comprised 1799 records with 23 African RCTs; for embase , the reference set comprised 763 records with 37 African RCTs. The medline filter set comprised 180 records with 17 African RCTs; the embase filter set comprised 98 records with 27 African RCTs. Sensitivity of the filter was 74% (medline ) and 73% (embase ). Addition of the filter improved precision from 1.3% to 9.4% (medline ) and from 5% to 28% (embase ). Conclusion: The African filter improved precision with some loss in sensitivity. Incomplete reporting of trial location in electronic bibliographic records restricts efficiency of geographic filters. Prospective trial registration should alleviate this.