Blair T. Johnson

Learn More
Past behavior guides future responses through 2 processes. Well-practiced behaviors in constant contexts recur because the processing that initiates and controls their performance becomes automatic. Frequency of past behavior then reflects habit strength and has a direct effect on future performance. Alternately, when behaviors are not well learned or when(More)
BACKGROUND Meta-analyses of antidepressant medications have reported only modest benefits over placebo treatment, and when unpublished trial data are included, the benefit falls below accepted criteria for clinical significance.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(More)
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 other-referent encoding strategies. Consistent with theory and(More)
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(More)
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(More)
BACKGROUND The purpose of this meta-analysis was to explore the efficacy of exercise as a nonpharmacologic intervention to reduce cancer-related fatigue (CRF) among adult cancer survivors. We also investigated how different components of the exercise prescription (Ex R(x)), methodologic considerations, and subject characteristics modulate CRF. METHODS A(More)
Attitudes toward the elderly have been examined in a number of empirical studies, yet the question of whether the elderly are viewed more negatively than younger persons has not been resolved. A meta-analysis of the literature was conducted to examine this question; results demonstrated that attitudes toward the elderly are more negative than attitudes(More)
OBJECTIVE To summarize studies that have tested the efficacy of human immunodeficiency virus (HIV) sexual risk-reduction interventions in adolescents. DATA SOURCES Reports were gathered from computerized databases, by contacting individual researchers, by searching conference proceedings and relevant journals, and by reviewing reference sections of(More)
BACKGROUND Exercise improves quality of life (QOL) in cancer survivors, although characteristics of efficacious exercise interventions for this population have not been identified. PURPOSE The present meta-analysis examines the efficacy of exercise interventions in improving QOL in cancer survivors, as well as features that may moderate such effects. (More)
OBJECTIVE The use of computers to promote healthy behavior is increasing. To evaluate the efficacy of these computer-delivered interventions, we conducted a meta-analysis of the published literature. METHOD Studies examining health domains related to the leading health indicators outlined in Healthy People 2010 were selected. Data from 75 randomized(More)