Reliable responses to a cardiovascular reactivity protocol: a replication study in a biracial female sample

This replication study was designed to examine the reliability of individual differences in cardiovascular responsivity to a standardized PC-based cognitive task protocol (Kamarck et al., 1992) in a female community sample. Thirty women, both black and white (ages 25-44 years), were administered the protocol twice with a 1-month retest interval using a mobile laboratory at a community-based testing site. Measures of heart rate and blood pressure reactivity were obtained comparing assessments taken at rest and during three protocol tasks. Preejection period, stroke volume, and total peripheral resistance changes were estimated using impedance cardiography assessments. As in previous studies with males, individual differences in heart rate and systolic and diastolic blood pressure responses to the protocol were highly reliable (.80 or greater) when data were aggregated across three tasks and two testing sessions. Reliability of cardiac contractility (preejection period) and stroke volume changes to these tasks exceeded .70. This reactivity assessment procedure has now produced reliable results in three studies and appears to be exportable across diverse samples and settings.