BackgroundAssessments of health-related quality of life and particularly utility values are important components of health economic analyses. Several instruments have been developed to measure utilities. However no consensus has emerged regarding the most appropriate instrument within a therapeutic area such as chronic pain. The study compared two instruments – EQ-5D and SF-6D – for their performance and validity in patients with chronic pain.MethodsPooled data from three randomised, controlled clinical trials with two active treatment groups were used. The included patients suffered from osteoarthritis knee pain or low back pain. Differences between the utility measures were compared in terms of mean values at baseline and endpoint, Bland–Altman analysis, correlation between the dimensions, construct validity, and responsiveness.ResultsThe analysis included 1977 patients, most with severe pain on the Numeric Rating Scale. The EQ-5D showed a greater mean change from baseline to endpoint compared with the SF-6D (0.43 to 0.58 versus 0.59 to 0.64). Bland–Altman analysis suggested the difference between two measures depended on the health status of a patient. Spearmans rank correlation showed moderate correlation between EQ-5D and SF-6D dimensions. Construct validity showed both instruments could differentiate between patient subgroups with different severities of adverse events and analgesic efficacies but larger differences were detected with the EQ-5D. Similarly, when anchoring the measures to a disease-specific questionnaire – Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) – both questionnaires could differentiate between WOMAC severity levels but the EQ-5D showed greater differences. Responsiveness was also higher with the EQ-5D and for the subgroups in which improvements in health status were expected or when WOMAC severity level was reduced the improvements with EQ-5D were higher than with SF-6D.ConclusionsThis analysis showed that the mean EQ-5D scores were lower than mean SF-6D scores in patients with chronic pain. EQ-5D seemed to have higher construct validity and responsiveness in these patients.

For the five largest EU countries, the societal burden of pain is considerable. The experience of pain far outweighs the contribution of more traditional explanations of HRQoL deficits as well as being the primary factor associated with increased provider visits, emergency room visits and hospitalizations.

The experience of pain, in particular severe daily pain, has a substantial negative association with labor force participation in these five European countries as well as reported absenteeism and presenteeism. As a measure of health status, it clearly outweighs other health status measures. Whether or not pain is considered as a disease in its own right, the experience of chronic pain, as defined here, presents policy makers with a major challenge. Programs to relieve the burden of pain in the community clearly have the potential for substantial benefits from societal, individual and employer perspectives.

Postoperative pain management is still insufficient, leading to major deficits, including patient suffering, impaired surgical recovery, longterm opioid intake, and postsurgical chronic pain. Yet, identifying the best treatment options refers to a heterogeneous outcome assessment in clinical trials, not always reflecting relevant pain-related aspects after surgery and therefore hamper evidence synthesis. Establishing a core outcome set for perioperative pain management of acute pain after surgery may overcome such limitations. An international, stepwise consensus process on outcome domains ("what to measure") for pain management after surgery, eg, after total knee arthroplasty, sternotomy, breast surgery, and surgery related to endometriosis, was performed. The process, guided by a steering committee, involved 9 international stakeholder groups and patient representatives. The face-to-face meeting was prepared by systematic literature searches identifying common outcome domains for each of the 4 surgical procedures and included breakout group sessions, world-caf é formats, plenary panel discussions, and final voting. The panel finally suggested an overall core outcome set for perioperative pain management with 5 core outcome domains: physical function (for a condition-specific measurement), pain intensity at rest, pain intensity during activity, adverse events, and self-efficacy. Innovative aspects of this work were inclusion of the psychological domain selfefficacy, as well as the specific assessment of pain intensity during activity and physical function recommended to be assessed in a condition-specific manner. The IMI-PROMPT core outcome set seeks to improve assessing efficacy and effectiveness of perioperative pain management in any clinical and observational studies as well as in clinical practice.

The cost-effectiveness study suggested that initiating 2nd line treatment in patients with severe non-malignant chronic pain in the UK with tapentadol instead of oxycodone improves patients' quality-of-life and is less costly. Key limitations when interpreting the results are the use of different sources to populate the model and restricted generalizability due to data extrapolation.