In this study, we evaluated the reliability of a newly developed method for pain assessment, which is based on perceptual matching by Pain Matcher, Cefar Medical AB, Lund, Sweden, during minor gynecological surgery. In addition, the responsiveness to two different anesthetic methods-electro-acupuncture or a fast-acting opiate, alfentanil, both in combination with a paracervical block-was estimated by using Pain Matcher and visual analog scale (VAS) assessments before and 2 h after surgery. Two hundred-twenty-three women (aged 22-38 yr) participated. The results show that Pain Matcher is a reliable method for pain assessments, with lack of random individual disagreement and with no statistical evidence of systematic disagreement in position or in concentration. The augmented rank-order coefficient (r(a)) values were excellent (0.95-1.00). When scales were used to detect true changes over time, there was no clear indication of responsiveness, mostly because of statistically significant random individual changes. However, the individual changes were much smaller for magnitude matching than for VAS. In conclusion, we would recommend the use of perceptual matching by Pain Matcher for pain assessment, because in this study it was a reliable and powerful in test-retest situations and had smaller individual changes than VAS after intervention. The Pain Matcher procedure was well accepted by the patients, and the results suggest that it may be useful when evaluating acute pre- and postoperative pain. IMPLICATIONS: We evaluated a new instrument for pain assessment. Our results show that this method is highly reliable, is well tolerated by the patients, is reported to be easy to use, and may be useful when evaluating acute pre- and postoperative pain.