Stated preferences of physicians and chronic pain sufferers in the use of classic strong opioids.

We conducted a two-stage study in France, Germany, Italy, Spain, Sweden, and the United Kingdom of the stated preferences of chronic pain sufferers treated with classic strong opioids and of physicians treating such patients. The qualitative stage identified attributes perceived important through focus groups with 84 pain sufferers and semistructured interviews with 11 physicians. The quantitative stage included online, discrete choice experiments (DCEs) in which respondents chose between hypothetical profiles or an opt-out in 15 choice tasks. The profile descriptions were based on the attributes elicited in the qualitative stage. DCEs were conducted for pain sufferers (N = 242) and physicians (N = 270) who passed a rationality test. Main-effects models were estimated by hierarchical Bayesian regression. Sufferers ranked nausea, pain impact, energy, alertness, and constipation; physicians ranked pain response, central nervous system (CNS) effects, nausea, dose form, and constipation in descending order of importance. Sufferers were unwilling to incur severe side effects to decrease pain and chose the opt-out in approximately one half of the choice tasks, whereas physicians were willing to trade between profiles. The models predicted physicians' choices better than those of pain sufferers. No age, sex, or country effects were seen, but stronger preferences were found among physicians treating noncancer (n = 40) than cancer pain and among the 55% of sufferers who had never discontinued long-term pain medication use. Sufferers' mean pain scores on an 11-point Likert scale were 4.0, 5.7, and 8.6 on their best, average, and worst days, respectively.