Systems and methods for detecting photoplethysmographic device usage

A system for determining positioning of a wrist-worn wearable photoplethysmography (PPG) device on a user, comprising:

• the wrist-worn wearable photoplethysmography device comprising:
• an energy transmitter disposed in the wrist-worn wearable photoplethysmography device configured to project energy towards a wrist of the user;
• an energy receiver disposed in the wrist-worn wearable photoplethysmography device configured to generate a user PPG signal based on the energy received at the energy receiver;
• communication circuitry;
• and
• a processor operatively connected to the energy transmitter, the energy receiver, and the communication circuitry;
• and
• a server in communication with the wearable photoplethysmography device,
• wherein the processor is configured to:
• determine wave features from the user PPG signal based on at least a portion of the projected energy transmitted from the energy transmitter;
• determine wave metric calculations of a set of wave metric calculations for the wave features;
• classify the signal by applying a validity classifier to at least one of the wave metric calculations to generate a validity score for the user PPG signal,
• wherein the validity classifier is configured to generate the validity score by
• receiving training wave metric calculations for known valid and known invalid signals, wherein the training wave metric calculations comprises one or more signal energy measurements,
• generating training validity scores corresponding to the known valid and known invalid signals, and
• generating the validity score for the user PPG signal based on the training validity scores for the known valid and known invalid signals;
• determine, based on the validity score and a validity threshold,
• whether the wearable photoplethysmography device is correctly positioned on the user,
• wherein the processor is further configured to one or more of stop operation, operate in a reduced capacity, or deactivate one or more components of the wrist-worn wearable PPG device when it is determined that the wrist-worn wearable PPG device is not correctly positioned based on a comparison of the validity score to the validity threshold.