A method and system for analyzing the status of a subject. A cordless recording device comprising a set of electrodes is attached on the forehead of the subject to collect brain wave signal data from the subject. Based on the brain wave signal data, status information indicative of the status of the subject during a measurement period is generated. A bioimpedance signal is further measured through two electrodes of the electrode set and heart rate data is derived from the bioimpedance signal. The heart rate data is utilized to enhance the quality of the status information, which is typically sleep state information. The invention also relates to a recording device attachable to the forehead of the subject. The recording may comprise a data memory for storing the data measured from the subject during the measurement period.
