A method and apparatus are provided for obtaining and processing ballistocardiograph data to determine a physiological condition of a subject. Ballistocardiograph data indicative of heart motion of the subject measured along a plurality of spatial axes by a sensor device which may comprise a three-axis accelerometer. The ballistocardiograph data is processed to determine processed data indicative of heart motion of the subject. Indications of physiological condition are determined based at least in part on the processed data. Processing may comprise aggregation of multidimensional data, determining magnitude of heart motion and derivative thereof, determining a thrust summation, determining an index value, outputting a report based on an index value, etc. Processing may be informed by operator input, such as a time window of interest or indications of interest.
