A subject electro-cardiogram data collection device (100;700; 1000; 1100; 1200) comprising: a removable ECG subject interface (125;727; 1027; 1127; 1227); having subject interface contacts (170; 1071a-e; 1271a-e); a power source (716;1015;1116;1215); a data collection unit (105; 705; 805; 905; 1005; 1105; 1205) comprising: a processor programmed to obtain physiological data from the ECG subject interface and store the physiological data in non-volatile memory (719; 1119), a data connector (745 948; 1145) being connected to the processor and having a male USB connector (280;880) configured to be physically connected to a universal data port on a computer and wherein the data collection unit is configured to detect power provided by the computer and, when connected to the computer, to upload the physiological data stored in the non-volatile memory to a remote service center via the computer, and data collection unit contacts (489;889;989; 1089a-e;1289a-e) configured to be physically connected to the subject interface contacts on the ECG subject interface; the data collection device being configured to provide power from the power source to the processor upon the ECG subject interface being connected to the data collection unit contacts and to interrupt power from the power source upon disconnection of the ECG subject interface from the data collection unit contacts. a removable ECG subject interface (125;727; 1027; 1127; 1227); having subject interface contacts (170; 1071a-e; 1271a-e); a power source (716;1015;1116;1215); a data collection unit (105; 705; 805; 905; 1005; 1105; 1205) comprising: a processor programmed to obtain physiological data from the ECG subject interface and store the physiological data in non-volatile memory (719; 1119), a data connector (745 948; 1145) being connected to the processor and having a male USB connector (280;880) configured to be physically connected to a universal data port on a computer and wherein the data collection unit is configured to detect power provided by the computer and, when connected to the computer, to upload the physiological data stored in the non-volatile memory to a remote service center via the computer, and data collection unit contacts (489;889;989; 1089a-e;1289a-e) configured to be physically connected to the subject interface contacts on the ECG subject interface; a processor programmed to obtain physiological data from the ECG subject interface and store the physiological data in non-volatile memory (719; 1119), a data connector (745 948; 1145) being connected to the processor and having a male USB connector (280;880) configured to be physically connected to a universal data port on a computer and wherein the data collection unit is configured to detect power provided by the computer and, when connected to the computer, to upload the physiological data stored in the non-volatile memory to a remote service center via the computer, and data collection unit contacts (489;889;989; 1089a-e;1289a-e) configured to be physically connected to the subject interface contacts on the ECG subject interface; the data collection device being configured to provide power from the power source to the processor upon the ECG subject interface being connected to the data collection unit contacts and to interrupt power from the power source upon disconnection of the ECG subject interface from the data collection unit contacts.