The emerging conceptualization of groups as information processors.

A selective review of research highlights the emerging view of groups as information processors. In this review, the authors include research on processing objectives, attention, encoding, storage, retrieval, processing, response, feedback, and learning in small interacting task groups. The groups as information processors perspective underscores several characteristic dimensions of variability in group performance of cognitive tasks, namely, commonality-uniqueness of information, convergence-diversity of ideas, accentuation-attenuation of cognitive processes, and belongingness-distinctiveness of members. A combination of contributions framework provides an additional conceptualization of information processing in groups. The authors also address implications, caveats, and questions for future research and theory regarding groups as information processors.

Reasons for the trend toward null findings in research on Type A behavior.

The findings of many studies conducted before 1978 suggest that Type A behavior (TAB) contributes to the development of coronary heart disease (CHD). In contrast, many recent studies have found no association between these variables. Through meta-analysis, several reasons for null findings are identified. First, a type of range restriction bias, disease-based spectrum (DBS) bias, produced many null findings. A study is vulnerable to DBS bias when researchers select only high-risk or diseased Ss for study. Second, self-report measures of TAB were often associated with null findings. Finally, null results were found for all studies that used fatal myocardial infarction as a disease criterion. In addition to identifying the reasons for null findings, this research suggests that TAB, as assessed by the structured interview, is associated with CHD. More Type As (70%) were found in diseased populations of middle-aged men than in healthy populations of middle-aged men (46%).

Disease based spectrum bias in referred samples and the relationship between type A behavior and coronary artery disease.

Using referred samples to study predictors of disease produces statistical problems that reduce the likelihood of obtaining statistically significant results even when a substantial relationship is present between a risk factor and a disease. The present paper refers to these problems as disease based spectrum (DBS) bias. DBS bias is present when subjects are directed into or excluded from the study sample according to their disease status. For example, healthy individuals are excluded from and diseased individuals are directed into referred samples. Therefore, DBS bias is present in referred samples. Examples from the literature on Type A behavior and coronary artery disease (CAD) are presented to illustrate how DBS bias reduces statistical associations. The results of the current research indicate DBS bias has reduced the association between Type A behavior and CAD in a number of studies reported in recent years. In addition, the present article discusses techniques for assessing and controlling for DBS bias.

Bias against overweight job applicants in a simulated employment interview.

This study assessed whether moderately obese individuals, especially women, would be discriminated against in a mock employment interview. Potential confounding factors were controlled by having 320 Ss rate videotapes of a job interview that used the same professional actors appearing as normal weight or made up to appear overweight by the use of theatrical prostheses. Results suggested that bias against hiring overweight job applicants does exist, especially for female applicants. Bias was most pronounced when applicants were rated by Ss who were satisfied with their bodies and for whom perceptions of their bodies were central to self-concept. The decision not to hire an obese applicant was, however, only partially mediated by personality attributions. Implications and limitations of these results are discussed.