Research comparing the leadership styles of women and men is reviewed, and evidence is found for both the presence and the absence of differences between the sexes. In contrast to the gender-stereotypic expectation that women lead in an interpersonally orientedstyle and men in a task-oriented style, female and male leaders did not differ in these two styles in organizationalstudies. However, these aspects of leadership style were somewhat gender stereotypic in the two other classes of leadership studies investigated, namely (a) laboratory experiments and (b) assessment studies, which were defined as research that assessed the leadership styles of people not selected for occupancy of leadership roles. Consistent with stereotypic expectations about a different aspect of leadership style, the tendency to lead democratically or autocratically, women tended to adopt a more democratic or participative style and a less autocratic or directive style than did men. This sex difference appeared in all three classes of leadership studies, including those conducted in organizations. These and other findings are interpreted in terms of a social role theory of sex differences in social behavior.In recent years many social scientists, management consultants, and other writers have addressed the topic of gender and leadership style. Some authors with extensive experience in organizations who write nontechnical books for management audiences and the general public have argued for the presence of sex differences in leadership style. For example, Loden (1985) maintained that there is a masculine mode of management characterized by qualities such as competitiveness, hierarchical authority, high control for the leader, and unemotional and analytic problem solving. Loden argued that women prefer and tend to behave in terms of an alternative feminine leadership model characterized by cooperativeness, collaboration of managers and subordinates, lower control for the leader, and problem solving based on intuition and empathy as well as rationality. Loden's writing echoes the androgynous manager theme developed earlier by Sargent (198 l), who accepted the idea that women and men, including those who are managers in organizations, behave stereotypically to some extent. Sargent advocated that managers of each sex adopt "the best" of the other This research was supported by National Science Foundation Grants BNS-8605256 and BNS-8807495. Preliminary reports of this research were presented at the Annual Meetings of the Eastern Psychological Association, April 1988; the Midwestern Psychological Association, April 1988; the International Congress o f Psychology, September 1988; and the American Psychological Association, August 1989. A table showing the effect sizes and study characteristics for each study included in the meta-analysis is available from the first author.We thank Anna Fairchild for assistance in locating studies and in recording and checking data. We also thank Judith Hall, Edwin E Hollander, Judi Komaki, Louis Sternberg, Howard ...

BackgroundMeta-analyses of antidepressant medications have reported only modest benefits over placebo treatment, and when unpublished trial data are included, the benefit falls below accepted criteria for clinical significance. Yet, the efficacy of the antidepressants may also depend on the severity of initial depression scores. The purpose of this analysis is to establish the relation of baseline severity and antidepressant efficacy using a relevant dataset of published and unpublished clinical trials.Methods and FindingsWe obtained data on all clinical trials submitted to the US Food and Drug Administration (FDA) for the licensing of the four new-generation antidepressants for which full datasets were available. We then used meta-analytic techniques to assess linear and quadratic effects of initial severity on improvement scores for drug and placebo groups and on drug–placebo difference scores. Drug–placebo differences increased as a function of initial severity, rising from virtually no difference at moderate levels of initial depression to a relatively small difference for patients with very severe depression, reaching conventional criteria for clinical significance only for patients at the upper end of the very severely depressed category. Meta-regression analyses indicated that the relation of baseline severity and improvement was curvilinear in drug groups and showed a strong, negative linear component in placebo groups.ConclusionsDrug–placebo differences in antidepressant efficacy increase as a function of baseline severity, but are relatively small even for severely depressed patients. The relationship between initial severity and antidepressant efficacy is attributable to decreased responsiveness to placebo among very severely depressed patients, rather than to increased responsiveness to medication.

In this review, the authors examine the basis for the mnemonic superiority that results from relating material to the self. A meta-analysis confirms the expected self-reference effect (SRE) in memory, with self-referent encoding strategies yielding superior memory relative to both semantic and otherreferent encoding strategies. Consistent with theory and research that suggest self-reference (SR) produces both organized and elaborate processing, the SRE was smaller (a) when SR is compared with other-reference (OR) rather than semantic encoding and (b) when the comparison tasks promote both organization and elaboration. Thus, the SRE appears to result primarily because the self is a well-developed and often-used construct that promotes elaboration and organization of encoded information. The authors discuss the implications of these and other findings for theories of the SRE and for future research.Throughout the history of psychology, researchers have used the self as a central part of their explanations of various phenomena (see Banaji & Prentice, 1994;G. T. Greenwald & Pratkanis, 1984;and James, 1890). A large body of research suggests that the self-structure is unique, relative to other concepts (e.g., those about other people; see Kihlstrom et al., 1988;Markus, 1977;and Rogers, Kuiper, & Kirker, 1977), in its motivational and affective implications as well as in its structure and content. Social psychologists have long posited an important affective role for the self-concept (e.g., C. W. Sherif, Sherif, & Nebergall, 1965;M. Sherif & Cantril, 1947). More recently, appraisal theories of emotion have emphasized the phenomenological importance of the self in the interpretation of events and the resulting effect on emotions (Fiske & Taylor, 1991). From a motivational standpoint, examples of the self's pervasive influence abound. For example, the tendency to attribute another person's behavior to dispositional factors but one's own behavior to situational factors presumably occurs because the self dominates one's phenomenal perspective (Ross & Nisbett, 1991;Storms, 1973). Similarly, both self-serving biases and defense mechanisms have been attributed to self-protective or self-enhancing

To examine how well the theories of reasoned action and planned behavior predict condom use, the authors synthesized 96 data sets (N = 22,594) containing associations between the models' key variables. Consistent with the theory of reasoned action's predictions, (a) condom use was related to intentions (weighted mean r. = .45), (b) intentions were based on attitudes (r. = .58) and subjective norms (r. = .39), and (c) attitudes were associated with behavioral beliefs (r. = .56) and norms were associated with normative beliefs (r. = .46). Consistent with the theory of planned behavior's predictions, perceived behavioral control was related to condom use intentions (r. = . 45) and condom use (r. = .25), but in contrast to the theory, it did not contribute significantly to condom use. The strength of these associations, however, was influenced by the consideration of past behavior. Implications of these results for HIV prevention efforts are discussed.Because condom use can prevent infection with HIV and other STDs, health agencies have designed various interdisciplinary efforts, oriented by behavioral prediction models, to persuade people to use condoms consistently. For example, the health belief model (Becker, 1974;Rosenstock, 1974) posits in part that increasing perceptions of vulnerability to HIV infection should increase precautionary behavior. Yet a recent quantitative synthesis found that chronic perceived vulnerability to HIV infection in members of high-risk groups is insufficient to motivate protective actions (Gerrard, Gibbons, & Bushman, 1996; but see Bryan, Aiken, & West, 1996). The limited support for the perceived-risk hypothesis suggests a need for other behavioral models of HIV-risk-related behavior.In the present article, we modeled condom use behavior on the basis of two general theories of behavior: (a) the theory of reasoned action (Ajzen & Fishbein, 1977, 1980Fishbein, 1980; Fishbein & Ajzen, 1975) and (b) the theory of planned behavior (Ajzen, 1988(Ajzen, , 1991 Correspondence concerning this article should be addressed to: Dolores Albarracín, Department of Psychology, University of Florida, Gainesville, Florida 32611. albarrac@psych.ufl.edu. HHS Public Access Author Manuscript Author ManuscriptAuthor ManuscriptAuthor Manuscript Ajzen & Driver, 1991;Ajzen & Madden, 1986;Schifter & Ajzen, 1985). Given that these models have predicted a wide range of behaviors successfully (see reviews by Ajzen, 1991; Eagly & Chaiken, 1993;Sheppard, Hartwick, & Warshaw, 1988) and have served as a basis for several HIV prevention efforts (e.g., Kamb, Dillon, Fishbein, Willis, & Project RESPECT Study Group, 1996; Kamb et al., 1998), we expected that they would also be valuable to predict condom use (cf. Sheeran & Orbell, 1998). The large number of studies that have now examined these models in relation to condom use (see Albarracín & Fishbein, 1993) and the variability of the findings suggest that a quantitative synthesis of this literature would prove valuable. Therefore, the purpose of the pre...

Defines involvement as a motivational state induced by an association between an activated attitude and the self-concept. Integration of the available research suggests that the effects of involvement on attitude change depended on the aspect of message recipients' self-concept that was activated to create involvement: (a) their enduring values (value-relevant involvement), (b) their ability to attain desirable outcomes (outcome-relevant involvement), or (c) the impression they make on others (impression-relevant involvement). Findings showed that (a) with value-relevant involvement, high-involvement subjects were less persuaded than low-involvement subjects; (b) with outcome-relevant involvement, high-involvement subjects were more persuaded than low-involvement subjects by strong arguments and (somewhat inconsistently) less persuaded by weak arguments; and (c) with impression-relevant involvement, high-involvement subjects were slightly less persuaded than lowinvolvement subjects.To understand the conditions under which people are persuaded by others, researchers have often invoked the concept of involvement. Although this construct was popular prior to M. Sherif and Cantril's (1947) work (see A. G. Greenwald's, 1982, review), their proposal that highly involving attitudes be regarded as components of the self-concept or ego was seminal to theory about involvement's impact on attitude change. According to M. Sherif and Cantril (1947), such attitudes "have the characteristic of belonging to me, as being part of me, as psychologically experienced" (p. 93).M. Sherif, C. W. Sherif, and their colleagues developed the implications of involvement (which they often called "ego involvement") for persuasion by giving it a major role in their social judgment-involvement approach, a theory of attitude change developed in the 1950s and early 1960s (Hovland, Harvey, & Sherif, 1957;C. W. Sherif, Sherif, & Nebergall, 1965;M. Sherif & Hovland, 1961). During this same period, Zimbardo (1960) introduced the concept of response involvement in order to predict attitude change in a social influence setting. In more A preliminary report of this research was presented at the meeting of the Midwestern Psychological Association, May 1987.We thank

This meta-analytic review of 232 effect sizes showed that, across five categories, attitudes were more negative toward older than younger adults. Perceived age differences were largest for age stereotypes and smallest for evaluations. As predicted by social role theory (Eagly, 1987), effect sizes were reduced when detailed information was provided about the person being rated. The double standard of aging emerged for evaluations and behavior/behavioral intentions, but was reversed for the competence category. Perceptions depended on respondent age also. Results demonstrated both the multi-dimensionality and the complexity of attitudes toward older adults (Hummert, 1999; Kite & Wagner, 2002).For over half a century, gerontologists have puzzled over North Americans' fascination with youth and their reluctance to accept aging gracefully. Initially, research on these issues was based on the assumption that negative attitudes toward older adults were widespread (Butler, 1969). Subsequent reviewers have reached different, and sometimes opposite conclusions. At the same time that Green (1981) 242 Kite, Stockdale, Whitley, and Johnson determined that negative age-related stereotypes were the norm, Lutsky (1980) concluded that age, in and of itself, was less important in determining attitudes toward older adults than were other types of information. More recent reviewers (Hummert, 1999; Kite & Wagner, 2002) echoed McTavish's (1971 conclusion; the answer to the seemingly simply question "Does ageism exist?" is not an unequivocal yes. Instead, people's views about aging are multidimensional, with both positive and negative elements.This article examines the complexities of age-related attitudes and stereotypes through a meta-analytic review of literature on ageism. Specifically, we update and expand upon Kite and Johnson's (1988) previous meta-analysis. Kite and Johnson reviewed the literature on this topic prior to December 1985, examining a total of 43 independent effect sizes. Thirty of those effect sizes indicated that people were more negative toward older than toward younger people, eleven indicated more negative attitudes toward younger than toward older people, and two indicated exactly no difference in attitudes toward the two groups. The overall effect size, as indexed by the d statistic was 0.39, indicating that attitudes toward older persons were more negative than attitudes toward younger persons by approximately onethird of a standard deviation.Although this finding indicated a bias against older adults, these effect sizes were not homogeneous. That is, the difference in attitudes expressed about older and younger adults varied widely across studies. Therefore, potential moderators of the effect sizes were explored to account for this variation. Results supported Lutsky's (1980) contention that people do not rely solely on information about age in judging older adults. Specifically, Kite and Johnson (1988) found that the context provided for the ratings moderated the results. That is, when specific info...

OBJECTIVES: This study examined whether HIV counseling and testing leads to reductions in sexual risk behavior. METHODS: The meta-analysis included 27 published studies that provided sexual behavior outcome data, assessed behavior before and after counseling and testing, and provided details sufficient for the calculation of effect sizes. The studies involved 19,597 participants. RESULTS: After counseling and testing, HIV-positive participants and HIV-serodiscordant couples reduced unprotected intercourse and increased condom use more than HIV-negative and untested participants. HIV-negative participants did not modify their behavior more than untested participants. Participants' age, volition for testing, and injection drug use treatment status, as well as the sample seroprevalence and length of the follow-up, explained the variance in results. CONCLUSIONS: HIV counseling and testing appears to provide an effective means of secondary prevention for HIV-positive individuals but, as conducted in the reviewed studies, is not an effective primary prevention strategy for uninfected participants. Theory-driven research with attention given to the context of testing is needed to further explicate the determinants of behavior change resulting from HIV counseling and testing, and the effectiveness of specific counseling approaches.

Computer-delivered interventions can lead to improved behavioral health outcomes at first post-intervention assessment. Interventions evaluating outcomes at extended assessment periods are needed to evaluate the longer-term efficacy of computer-delivered interventions.