Smith W S, O'Brien C
Biomed Eng. 1976 Apr;11(4):128-31.
Using miniature cassette tape recorders, measurement of ECG and other physiological measures is possible in industrial or working situations. The development of a semi-automatic high speed processing system for analysis of the tape recorded data is described. This system decodes the signals on the tape, converts ECG to heart rate and presents a listing of the heart rate variation over the recording period, which may be up to 24 hours. A punched paper tape copy of the listing is used for input into a mainframe computer for subsequent analysis. The recorders and processing system have been used extensively for three years on a study of industrial work stress, and have proved reliable, accurate, and of sufficient sensitivity for in-depth analysis. They allow considerable data to be collected, permitting the thorough statistical analysis necessary for the interpretation of complex physiological responses.