Predictors of differences between Type A and B individuals in heart rate and blood pressure reactivity.

Past estimates of the magnitude of Type A-B differences in cardiovascular reactivity are probably overly conservative. In addition, it is unclear which situations are more likely to elicit excessive reactivity in Type As. The present meta-analysis found that, overall, Type As had greater heart rate (mean d = .22), diastolic blood pressure (d = .22), and especially systolic blood pressure responses (d = .33) than Type Bs; these effect sizes were small but relatively consistent. However, Type As showed especially greater cardiovascular reactivity in situations characterized as having (a) positive or negative feedback evaluation, (b) socially aversive elements such as verbal harassment or criticism, and (c) elements inherent in playing video games. Measures of time urgency, Type A assessment method, and gender were not found to be strongly related to A-B differences in cardiovascular reactivity. Future studies that use more "Type A-relevant" situations will probably find greater effects.