Methods and system for characterising tremors

A method of determining a tremor status in a subject, said subject having an involuntary tremor symptomatic of a neurological disorder, the method comprising:

• determining, using the method of any preceding method claim, an index value for the subject, said index value characterising the stability of the tremor;
• comparing the index value to a database of known index values, said known index values being previously generated from subjects having a known tremor status;
• and
• determining the tremor status of the subject based on the index value comparison.

A system for calculating a value indicative of a tremor stability of a subject having an involuntary tremor symptomatic of a neurological disorder, said system comprising:

• a processor configured to:
• receive sensor data measuring tremor data of the subject, said tremor data comprising tremor cycles measuring periodic variation in movement of the subject due to the tremor;
• determine instantaneous frequencies for tremor cycles of the tremor;
• calculate frequency variations between the tremor cycles;
• and
• determine an index value indicative of the distribution of the frequency variations with instantaneous frequency.

A method of analysing a series of tremor cycles to determine a tremor status, said method comprising the steps of:

• analysing a tremor series comprising a plurality of tremor cycles;
• determining an instantaneous frequency for each tremor cycle;
• determining an instantaneous variation between the instantaneous frequencies of adjacent tremor cycles within the series;
• comparing the instantaneous variation to the range of determined instantaneous frequencies to determine a distribution of instantaneous variations;
• and
• determining an index value of the distribution of the instantaneous variations, said index value defining a tremor status.

A method of collecting tremor information from a subject, said subject having an involuntary tremor symptomatic of a neurological disorder, the method comprising:

• sensing a tremor in the subject;
• measuring the tremor for a predefined time;
• identifying a series of tremor cycles from the measured tremor;
• determining an instantaneous frequency for each tremor cycle and collating the instantaneous frequencies;
• determining an instantaneous variation between the instantaneous frequencies of each pair of adjacent tremor cycles within the series;
• comparing the instantaneous variation to the collation of determined instantaneous frequencies to determine a distribution of instantaneous variations;
• and
• determining an index value of the distribution of the instantaneous variations.