An apparatus for determining data on a human subject's heart rate, respiration rate, and / or blood pressure based on a pulse waveform analysis, and an apparatus for determining a medical condition of a human subject. The apparatus for determining data includes a control unit and means for providing pulse wave data indicative of a heartbeat of a human subject. Subjects have body height, age, and gender and are further characterized by smokers or non-smokers and by percentages of body fat (eg, BMI, BFP, etc.). The control unit receives the pulse-wave data, selects a portion of the pulse-wave data representing a plurality of cardiac cycles, and applies the pulse-wave data representing the plurality of cardiac cycles to the pulse- Determining blood pressure variability based on the blood pressure； Determining respiration rate variability based on pulse wave data of a portion of the pulse wave data representing a plurality of cardiac cycles； And determines the heart rate variability based on the pulse wave data of the portion of the pulse wave data representing a plurality of cardiac cycles. In addition, at least one correlation value based on at least two of blood pressure variability, respiration rate variability, and heart rate variability is determined, and the medical condition of the subject is determined based on at least one correlation value. An apparatus for determining a medical condition of a human subject includes a control unit and means for providing pulse wave data indicative of a heart beat of a human subject. The control unit is configured to receive the pulse wave data, select a portion of the pulse wave data representing a plurality of cardiac cycles, determine a first index indicating the heart rate variability based on the pulse wave data of the portion of the pulse wave data representing the plurality of heart cycles Determining a second index indicative of heart rate variability based on pulse wave data of a portion of pulse wave data indicative
