A data collection system collects and stores physiological data from an ambulatory patient at a high resolution and/or a high data rate (“more detailed data”) and sends a low-resolution and/or downsampled version of the data (“less detailed data”) to a remote server via a wireless network. The server automatically analyzes the less detailed data to detect an anomaly, such as an arrhythmia. A two-tiered analysis scheme is used, where the first tier is more sensitive and less specific than the second tier. If the more sensitive analysis detects or suspects the anomaly, the server signals the data collector to send more detailed data that corresponds to a time period associated with the anomaly. The more specific second tier analyses the more detailed data to verify the anomaly. The server may also store the received data and make it available to a user, such as via a graphical or tabular display.
