['Our aim was to evaluate visualization methods for specific tasks performed with personal healthcare e-record systems for lay adults and older patients. We investigated common visualization methods for data entry and follow-up of personal and clinical information for self-control of blood coagulation functions.', 'Twenty-five old (72.2 +/- 5.5 years) and 25 young (30.4 +/- 4.9 years) participants completed tasks based on common scenarios, on experimental Web sites with hidden tracking programs. Functional parameters (time, accuracy), subjective parameters (preference, satisfaction), and physiological parameters (heart rate, skin temperature, sweat, respiratory rate, and muscle tension) monitored with miniature sensors were used.', 'Total time for data entry and information follow-up were significantly longer for older compared with younger participants, with no significant differences in accuracy (errors), in stress-related physiological parameters, in preferences, or in satisfaction between age group. The Menu display was the significantly preferred configuration for data entry in both age groups, based on functional, physiological, and subjective criteria (p < 0.05, Duncan test). The Calendar configuration was significantly preferred for mixed tasks of follow-up and information retrieval, in both age groups, based on functional, physiological, and subjective criteria (p < 0.05, Duncan test).'] Do evaluation of data display for patient-oriented electronic record of anticoagulant therapy?