Combining effect size estimates in meta-analysis with repeated measures and independent-groups designs

When a meta-analysis on results from experimental studies is conducted, differences in the study design must be taken into consideration. A method for combining results across independent-groups and repeated measures designs is described, and the conditions under which such an analysis is appropriate are discussed. Combining results across designs requires that (a) all effect sizes be transformed into a common metric, (b) effect sizes from each design estimate the same treatment effect, and (c) meta-analysis procedures use design-specific estimates of sampling variance to reflect the precision of the effect size estimates.     

The Nature and Meaning of the Near-Death Experience for Patients and Critical Care Nurses

This study was designed to develop a conceptual framework for the near-death experience (NDE), reflecting its nature and meaning for the patient and the critical care nurse. The study used naturalistic inquiry to examine the question: What is the nature and meaning of an NDE and how has it influenced the individual's view of the self, the future, and feelings and beliefs about life and death? The NDE Scale (Greyson, 1983) was used with patients and semi-structured interview guides were used with both nurses and patients to explore the NDE from a comprehensive perspective. An NDE was defined as the report of “unusual” recollections associated with a period of unconsciousness during either serious illness or injury, or resuscitation from a cardiac or respiratory arrest. The sample included 12 patients who experienced an NDE and 19 nurses who cared for patients who experienced NDEs. This study highlighted the emotional aspects of the NDE. Patients described how the NDE transformed their lives and nurses reported how their experiences with patients changed them personally and professionally.     

Attentional resource and processing speed limitations during sentence processing in Parkinson's disease

Several studies have suggested that patients with Parkinson's disease (PD) have sentence comprehension difficulty in part because of their limited executive resources. However, these assessments confound the executive resources contributing to sentence comprehension with the resources needed for task performance. In the present study, we used a word detection technique that minimizes task demands in order to evaluate attentional and processing speed resources during the comprehension of simple sentences without subordinate clauses and sentences containing subject-relative and object-relative center-embedded subordinate clauses. We found that PD patients have poor sensitivity to phonetic errors embedded in unbound grammatical morphemes, regardless of the clausal structure of the sentence, suggesting difficulty attending to grammatical morphemes. We also found that PD patients are significantly slowed in their sensitivity to phonetic errors in content words embedded in object-relative center-embedded sentences. Slowed sensitivity to content words in object-relative sentences was correlated with timed executive measures of planning. On a traditional measure of comprehension, these PD patients were impaired for sentences containing object-relative center-embedded clauses compared to sentences with subject-relative center-embedded clauses, and comprehension of object-relative sentences was correlated with executive measures. Our findings are consistent with the claim that limited executive resources for strategic attention and processing speed contribute to the sentence comprehension difficulties of PD patients.     

From statistical associations to causation: what developmentalists can learn from instrumental variables techniques coupled with experimental data

In this article, the authors aim to make accessible the careful application of a method called instrumental variables (IV). Under the right analytic conditions, IV is one promising strategy for answering questions about the causal nature of associations and, in so doing, can advance developmental theory. The authors build on prior work combining the analytic approach of IV with the strengths of random assignment design, whether the experiment is conducted in the lab setting or in the "real world." The approach is detailed through an empirical example about the effects of maternal education on children's cognitive and school outcomes. With IV techniques, the authors address whether maternal education is causally related to children's cognitive development or whether the observed associations reflect some other characteristic related to parenting, income, or personality. The IV estimates show that maternal education has a positive effect on the cognitive test scores of children entering school. The authors conclude by discussing opportunities for applying these same techniques to address other questions of critical relevance to developmental science.     

Negotiators who give too much: unmitigated communion, relational anxieties, and economic costs in distributive and integrative bargaining

A series of studies found that the personality dimension of unmitigated communion (H. L. Fritz & V. S. Helgeson, 1998) leads negotiators to make concessions to avoid straining relationships. Results indicate that even within the population of successful business executives, this dimension of relational anxiety can be identified distinctly from more general relational orientations, such as agreeableness, and that it distinctly predicts accommodating tendencies in everyday conflicts. In economic games, unmitigated communion predicts giving in contexts in which the relational norm of reciprocity applies, but not in contexts tapping instrumental or altruistic motives for cooperation. In distributive negotiations, the effect of unmitigated communion in lowering a negotiator's outcome is mediated by prenegotiation anxieties about relational strain and plans to make large concessions if needed to avoid impasse (lower reservation points). In integrative negotiations, high unmitigated communion on both sides of the negotiation dyad results in relational accommodation, evidenced by decreased success in maximizing economic joint gain but increased subjective satisfaction with the relationship.     

Patterns of psychosocial risk and long-term outcomes in rheumatoid arthritis

This study examined the extent to which patterns of psychosocial risk were uniquely associated with long-term outcomes of rheumatoid arthritis (RA), after demographic factors and self-reported symptom severity over time were accounted for. Data were collected over an 8-year period from 561 individuals with RA who were participants in the ongoing UCSF RA Panel Study in 1995. Panel members were interviewed annually, using a comprehensive structured telephone interview. Psychosocial factors assessed included mastery, perceptions about adequacy of social support, the impact of RA and self-assessed ability to cope with RA and satisfaction with health and function. Cluster analysis of psychosocial factors identified three distinctive patterns/levels of psychosocial risk (high, medium and low risk). The unique effects of psychosocial risk status on changes in depressive symptoms, basic functional limitations, global pain ratings and average annual doctor visits over an 8-year period were estimated, using growth curve analyses. Analyses controlled for demographic factors (gender, marital/partner status, education, age and ethnicity), disease duration and year in the panel and time-varying self-reported symptom severity (morning stiffness, swollen joint counts, co-morbid medical conditions, extra-articular RA symptoms and changes in joint appearance), as well as self-reported medications taken over time (disease-modifying antirheumatic drugs [DMARDS], and prednisone). Overall, 32.4% of total variance in depressive symptoms was accounted for by the fully-estimated model, with 12.9% uniquely associated with psychosocial risk status. Half of the total variance (50.0%) in basic functional limitations was explained, with 12.1% of variance uniquely predicted by psychosocial risk status. Psychosocial risk status accounted for comparatively little total explained variance in global pain ratings (total = 38.6%, incremental = 3.2%), and average annual total doctor visits (total = 10.9%, incremental = 1.5%). Thus, psychosocial risk factors are more closely linked to depressive symptoms and function over time. Global pain and utilization appear to be more closely related to disease factors.     

It was the best of times, it was the worst of times: doctoral students' experiences of family therapy research training through alternative forms of data representation

In this study, we interviewed 14 doctoral students from 10 COAMFTE-accredited doctoral programs to learn more about how they experienced their research training and what they might suggest to strengthen the research culture in their training programs. We solicited somewhat unconventional data--metaphors, poetry, free associations, critical experiences--to (a) tap into our participants' underlying thought processes, (b) capture the multifaceted nature of their doctoral research training, and (c) represent the richness of our participants' subjective experiences. The themes we identified reflect both positive and negative research training experiences and suggest several ways that family therapy program faculty might improve their programs' research training and culture.     

Selective interference with the use of visual images in the symbolic distance paradigm

Eight experiments investigated the effects of visual, spatial, auditory, and executive interference on the symbolic comparison of animal size and ferocity, semantic goodness of words, and numbers. Dynamic visual noise (DVN) and the reading of visually presented stimulus items were shown to selectively interfere with response times on the animal size comparison task, though the slope of the symbolic distance function remained unchanged. Increased change of DVN significantly increased interference, but interference was reduced by equiluminant DVN. Spatial tracking reduced the slope of the symbolic distance function in contrast to an executive task that only increased mean latency and errors for all comparisons. Results suggest that the generation of an image is necessary for size comparison, but neither imagery nor executive function is responsible for the frequently observed distance-time function.