An embodiment of a method for assessing cardiovascular disease in a user with a body region using a mobile computing device including a camera module, includes receiving a time series of image data of a body region of the user, the time series of image data captured during a time period; generating a photoplethysmogram dataset from the time series of image data; generating a processed PPG dataset; determining a cardiovascular parameter value of the user based on the processed PPG dataset; fitting a chronobiological model to (1) the cardiovascular parameter value, and (2) a subsequent cardiovascular parameter value, characterizing a cardiovascular parameter variation over time of the user based on the fitted chronobiological model; and presenting an analysis of the cardiovascular parameter variation to the user at the mobile computing device.