On the affective nature of chronic pain

The aim of the present study was to test if the Spanish Version of the McGill Pain Questionnaire (MPQSV) can account for differences between chronic: and acute pain patients and to test the equality of Factor Structures in both samples. The sample was made up of 175 chronic pain patients and 176 acute pain sufferers. The mean scores of the Sensory, Affective and Total Subscales of the MPQ-SV, intercorrelations between subscales and reliability indexes were compared in both samples and a multisample confirmatory factor analysis was carried out. The chronic pain sample showed higher scores than the acute pain sample in all the MPQ-SV scales: affective, sensory and total. On the other side, the intercorrelations between the MPQ-SV scales and its reliability indexes were more intense in chronic than in acute patients. Finally, the factorial structure of MPQ-SV according to a tridimensional model, could not be generalized to acute and chronic pain samples. In conclusion, MPQ accounted the differences between chronic and acute pain, the emotional distress of chronic pain was translated into high scores to all the MPQ scales.