Personal health data collection

A personal hand-held monitor (PHHM) for the measurement of a subject's blood pressure (BP) and, optionally, one or more other vital signs, comprising a housing located on a personal hand-held computing device (PHHCD) or a hand-held component of a computing system;

• a blood flow occlusion device located in the housing such that, when the housing is located on the PHHCD or the hand-held component, an open surface of the blood flow occlusion device is available to be pressed against a body part of the subject or to have a body part of the subject pressed against it;
• a pressure sensor adapted to provide an electrical signal indicative of the pressure applied to or by the open surface;
• an optical blood flow detecting device configured to detect the flow of blood in the body part of the subject when pressure is applied to or by the open surface;
• and
• a device configured to receive electrical signals from the pressure sensor and the optical blood flow detecting device and for transmitting electrical signals indicative of the pressure and blood flow to the processor of the PHHCD or the computing system,
• wherein:
• the processor of the PHHCD or computing system is adapted to process signals acquired by the pressure sensor and the optical blood flow detecting device to provide at least a measurement of the BP of a subject,
• the processor is adapted to calculate a ratio of the amplitude of the pressure fluctuations on each pulse to the optical signals on each pulse to provide an estimate of the rotation of the body part relative to the blood flow occlusion device;
• and
• the processor is further adapted to carry out a process to measure a diastolic blood pressure (DBP) value and a systolic blood pressure (SBP) value using the estimate;
• and either
• the DBP and the SBP values are estimated in such a way that the difference between the measured optical signals and those that would be generated by the estimation of the DBP and SBP values is minimized or
• the DBP and the SBP values are estimated in such a way that the difference between the measured incremental pressure signals and those that would be generated by the estimation of the DBP and SBP values is minimized.