A method, system, and device for measuring and evaluating hair loss over time is disclosed. A instrumented comb device includes a power source, a controller, and associated sensors. The controller receives signals from the sensors, including a contact sensor to detect contact with a scalp and obtain a hair count, and a magnetic compass to determine location on the scalp. The controller includes one or more processors that acquire and record the detected contact information and determined location information as the comb device is stroked over a scalp, and measure hair density based on the contact information and location information. The instrumented comb can communicate with a remote information system or a mobile device for auxiliary processing and display. Machine learning of the remote information system allows for recognizing hair density or prediction of future trends in hair density over time using data recorded by the sensors.
