The epistemology and ethics of chronic disease research: Further lessons from ECMO

Robert Truog describes the controversial randomized controlled trials (RCTs) of extracorporeal membrane oxygenation (ECMO) therapy in newborns. Because early results with ECMO indicated that it might be a great advance, saving many lives, Truog argues that ECMO should not have been tested using RCTs, but that a long-term, large-scale observational study of actual clinical practice should have been conducted instead. Central to Truog’s argument, however, is the idea that ECMO is an unusual case. Thus, it is an open question whether Truog’s conclusions can be extended to other areas of medical research. In this paper, I look at epistemological and ethical issues arising in the care of patients with chronic diseases, using ECMO as a starting point. Both the similarities and the dissimilarities of these two cases highlight important issues in biomedical research and support a conclusion similar to Truog’s. Observational studies of clinical practice provide the best evidence to inform the treatment of patients with chronic disease.     

Stress management interventions for HIV+ adults: a meta-analysis of randomized controlled trials, 1989 to 2006.

OBJECTIVE: Numerous studies document that stress accelerates disease processes in a variety of diseases including HIV. As a result, investigators have developed and evaluated interventions to reduce stress as a means to improve health among persons living with HIV. Therefore, the current meta-analysis examines the impact of stress-management interventions at improving psychological, immunological, hormonal, and other behavioral health outcomes among HIV+ adults. DESIGN: This meta-analytic review integrated the results of 35 randomized controlled trials examining the efficacy of 46 separate stress management interventions for HIV+ adults (N=3,077). MAIN OUTCOME MEASURES: Effect sizes were calculated for stress processes (coping and social support), psychological/psychosocial (anxiety, depression, distress, and quality of life), immunological (CD4+ counts and viral load), hormonal (cortisol, dehydroepiandrosterone sulfate [DHEA-S], cortisol/DHEA-S ratio, and testosterone) and other behavioral health outcomes (fatigue). RESULTS: Compared to controls, stress-management interventions reduce anxiety, depression, distress, and fatigue and improve quality of life (d+s=0.16 to 0.38). Stress-management interventions do not appear to improve CD4+ counts, viral load, or hormonal outcomes compared with controls. CONCLUSION: Overall, stress-management interventions for HIV+ adults significantly improve mental health and quality of life but do not alter immunological or hormonal processes. The absence of immunological or hormonal benefits may reflect the studies' limited assessment period (measured typically within 1-week postintervention), participants' advanced stage of HIV (HIV+ status known for an average of 5 years), and/or sample characteristics (predominately male and White participants). Future research might test these hypotheses and refine our understanding of stress processes and their amelioration.     

Expect the unexpected: failure to anticipate similarities leads to an intergroup forecasting error

People often expect interactions with outgroup members to go poorly, but little research examines the accuracy of these expectations, reasons why expectations might be negatively biased, and ways to bring expectations in line with experiences. The authors found that intergroup interactions were more positive than people expected them to be (Pilot Study, Study 1). One reason for this intergroup forecasting error is that people focus on their dissimilarities with outgroup members (Study 1). When the authors focused White participants' attention on the ways they were similar to a Black participant, their intergroup expectations changed to match their positive experiences (Studies 2 & 3). Regardless of focus, Whites expected to have pleasant intragroup interactions, and they were accurate (Study 4).     

Recall of details never experienced: Effects of age,repetition, and semantic cues

To test theoretical predictions about the role of meaning connections in false memory, the effects of semantic cues and list repetition on children's false memories were evaluated across early childhood to mid-adolescence using the Deese–Roediger–McDermott (DRM) paradigm. True recall and false recall increased from 7 to 13 years. Study list repetition increased true recall of list words with the magnitude of this effect largest in the older children and adolescents. Repetition reduced false recall of critical lures in all age groups. Consistent with theoretical predictions, false recall of critical lures increased when children were informed of the thematic gist of each list prior to study.     

Language functioning after bilateral prefrontal leukotomy

Three groups of patients with orbital frontal lesions secondary to leukotomy were compared to psychiatric and normal control groups on a series of tasks involving language. The results indicated that chronic orbital frontal lesions, at least in the patients in this study, do not affect language as defined by the tasks used in the study. The frontal lobes, when implicated in language, appear to require dorsal-lateral or medial cortical involvement.     

PRIMING FROM THE ATTENTIONAL BLINK:

Abstract —When people must detect several targets in a very rapid stream of successive visual events at the same location, detection of an initial target induces misses for subsequent targets within a brief period. This attentional blink may serve to prevent interruption of ongoing target processing by temporarily suppressing vision for subsequent stimuli. We examined the level at which the internal blink operates, specifically, whether it prevents early visual processing or prevents quite substantial processing from reaching awareness. Our data support the latter view. We observed priming from missed letter targets, benefiting detection of a subsequent target with the same identity but a different case. In a second study, we observed semantic priming from word targets that were missed during the blink. These results demonstrate that attentional gating within the blink operates only after substantial stimulus processing has already taken place. The results are discussed in terms of two forms of visual representation, namely, types and tokens.     

Laterality effects in risk preference: A test of portfolio theory

A central assumption in portfolio theory of risk preference is that for games with expected value constant the preference ordering of an individual should exhibit a single peaked preference function. This assumption was tested by determining the level of stochastic transitivity satisfied by triples of pairwise preference proportions among eight gambles. In only a small percentage of cases were the predicted levels of stochastic transitivity not satisfied. It was concluded that the results provided strong support for portfolio theory.     

EFFECT OF SUPPORTED EMPLOYMENT ON THE VOCATIONAL OUTCOMES OF PERSONS WITH TRAUMATIC BRAIN INJURY

This paper reports the job placement of 5 males with severe traumatic brain injury. An individual placement model of supported employment was used. All individuals were placed in competitive employment and received staggered intervention over time by trained employment specialists. A multiple baseline design across persons was used to evaluate results. All individuals had been unable to work consistently or at all in competitive work environments. The range of wages was $4.25 to $5.00 per hour with an average of 339 hours of employment specialist intervention time required per case. The major problems experienced by employment specialists were insubordinate and disruptive behaviors as well as other inappropriate social behaviors displayed at the job site.