According to an aspect of the present inventive concept there is provided a method for determining a nociceptive withdrawal reflex threshold of a person, the method comprising: applying a plurality of stimulations to a person with different stimulation intensity levels in accordance with a stimulation intensity algorithm, wherein the plurality of stimulations comprises at least one stimulation having an intensity level provoking a spinal cord withdrawal reflex in the person, recording electromyographic data representative of muscle activity of the person in response to each stimulation of the plurality of stimulations, and processing the stimulation intensity levels and the electromyographic data according to a threshold calculation algorithm to calculate a measure of the nociceptive withdrawal reflex threshold of the person. There is also provided a corresponding system.