Test-retest reliability of inotropic and chronotropic measures of cardiac reactivity.

This study evaluated the retest reliability of a number of inotropic and chronotropic indexes of cardiovascular reactivity to mental arithmetic stress over a 1-week interval. Differential habituation effects of the dependent measures were also assessed. 15 male and 15 female undergraduate Ss were administered a mental arithmetic task (serial subtractions by 13 from a 4-digit number) for 1-min on two successive weeks while their electrocardiogram and impedance cardiogram were recorded. Dependent measures included HR, PEP, HI, SV and CO. Results indicate that all dependent measures were reliable.