Shorter Articles and Notes an Optimum Interval in the Assessment of Pain Threshold

When the Limiting Method is used to measure heat-pain threshold, the observed threshod has been shown to depend on the size of the stimulus increment used (Haslam, 1965). An experiment is reported here which repeats a finding of the experiment referred to above that the variability of threshold is relatively large when the stimulus increment is small. A statistical analysis of the data shows that the previously untested hypothesis that pain threshold is uniform over the population (Hardy, Wolff and Goodell, 1952) is a reasonable one. The psychological implications of threshold variability are discussed in the light of a theoretical model, and a criterion for an optimum interval in the assessment of heat-pain threshold is discussed.