Data logging technology in ambulatory medical instrumentation

This paper reviews the advancements made in ambulatory data logging used in the study of human subjects since the inception of the analogue tape based data logger in the 1960s. Research into the area of ambulatory monitoring has been rejuvenated due to the development of novel storage technologies during the 1990s. Data logging systems that were previously impractical due to lack of processing power, practical size and cost are now available to the practitioner. An overview of the requirements of present day ambulatory data logging is presented and analogue tape, solid-state memory and disk drive storage recording systems that have been described in the literature are investigated in detail. It is proposed that digital based technology offers the best solution to the problems encountered during human based data logging. The appearance of novel digital storage media will continue the trend of increased recording durations, signal resolution and number of parameters thus allowing the momentum gained throughout the last several decades to continue.