Engagement-involvement and blood pressure change: a methodological inquiry

In a study that examined further Singer's model of engagement-involvement in a community nursing setting, 31 black inner-city women conversed informally with a nurse while their blood pressure was monitored at two-minute intervals using a Hoffman-LaRoche Arteriosonde. Type A (coronary-prone) and hypertensive subjects were judged to not display greater engagement than type B and normotensive subjects, respectively. Within-subject correlations between observers' ratings of engagement and blood pressure showed substantial differences across subjects. Nevertheless, for correlations based on engagement judgments corresponding to the minute immediately preceding the blood pressure determination the mean within-subject values ranged from .14 to .32 (mean = .20) and were all significantly different from zero. Attention is directed to the need for refining the criteria used for judging engagement and to identifying patients for whom increased engagement may invalidate blood pressure measurements in a clinical setting.