Pain is widespread. Many scales have been used for measuring clinical outcomes of pain, but few are preference-based instruments. OBJECTIVES: To compare scores derived from the Box-Score-11 (BS-11), a clinical scale widely used for measuring pain, and the Pain attribute (PA) of the Health Utilities Index (HUI-III), a preference-based instrument. METHODS: Patients (≥18 years) were recruited from pain clinics in four Canadian metropolitan areas (Toronto, Ottawa, Edmonton, Vancouver) and were administered both scales, assessing their average pain level over the previous four weeks. Kendall's tau-b was calculated between score sets and the proportions of the scores derived from the BS-11 that mapped onto each of the five PA scores of the HUI-III. RESULTS: Of 516 questionnaires completed, 6 had missing information, leaving 510 for analysis. The average age was 49.5±11.9 years; 70% were female. Tau-b was reasonably large and statistically significant between the scales ( = 0.685, P<0.001). No patients scored 0 on either scale, as only patients with pain were included. Two patients scored 1 and yielded inconclusive results. All, except one, of the remaining BS-11 scores mapped at ≥60% onto PA scores of the HUI-III respectively: 2 to 2, 3 to 2, 4 to 3, 5 to 3, 7 to 4, 8 to 4, 9 to 5 and 10 to 5; 6 on the BS-11 was mapped onto 4 on the HUI-III with 53% of answers. Scores 2 and 10 had best mapping (88% and 94%). The overall correspondence was considered excellent. CONCLUSIONS: This study demonstrated that scores from the BS-11 can be mapped onto the PA component of the HUI-III.