Clinicaltrials.gov identifier: NCT01467102.

UNLABELLED: PAIN OUT is a European Commission-funded project aiming at improving postoperative pain management. It combines a registry that can be useful for quality improvement and research using treatment and patient-reported outcome measures. The core of the project is a patient questionnaire-the International Pain Outcomes questionnaire-that comprises key patient-level outcomes of postoperative pain management, including pain intensity, physical and emotional functional interference, side effects, and perceptions of care. Its psychometric quality after translation and adaptation to European patients is the subject of this validation study. The questionnaire was administered to 9,727 patients in 10 languages in 8 European countries and Israel. Construct validity was assessed using factor analysis. Discriminant validity assessment used Mann-Whitney U tests to detect mean group differences between 2 surgical disciplines. Internal consistency reliability was calculated as Cronbach's alpha. Factor analysis resulted in a 3-factor structure explaining 53.6% of variance. Cronbach's alpha at overall scale level was high (.86), and for the 3 subscales was low, moderate, or high (range, .53-.89). Significant mean group differences between general and orthopedic surgery patients confirmed discriminant validity. The psychometric quality of the International Pain Outcomes questionnaire can be regarded as satisfactory. PERSPECTIVE: The International Pain Outcomes questionnaire provides an instrument for postoperative pain assessment and improvement of quality of care, which demonstrated good psychometric quality when translated into a variety of languages in a large European and Israeli patient population. This measure provides the basis for the first comprehensive postoperative pain registry in Europe and other countries. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 3 Abstract PAIN OUT is a European Commission-funded project aiming at improving postoperative pain (POP) management. It combines a registry that can be useful for quality improvement (QI) and research using treatment and patient-reported outcome measures. Core of the project is a patient questionnaire -the International Pain Outcomes questionnaire (IPO) that comprises key patient level outcomes of POP management including pain intensity, physical and emotional functional interference, side effects, and perceptions of care. Its psychometric quality after translation and adaptation to European patients is the subject of this validation study. The questionnaire was administered to 9,727 patients in 10 langu...

Patient ratings of satisfaction with their postoperative pain treatment tend to be high even in those with substantial pain. Determinants are poorly understood and have not previously been studied in large-scale, international datasets. PAIN OUT, a European Union-funded acute pain registry and research project, collects patient-reported outcome data on postoperative day 1 using the self-reported International Pain Outcome Questionnaire (IPO), and patient, clinical, and treatment characteristics. We investigated correlates of satisfaction and consistency of effects across centres and countries using multilevel regression modelling. Our sample comprised 16,868 patients (median age 55 years; 55% female) from 42 centres in 11 European countries plus Israel, USA, and Malaysia, who underwent a wide range of surgical procedures, for example, joint, limb, and digestive tract surgeries. Median satisfaction was 9 (interquartile range 7-10) on a 0-10 scale. Three IPO items showed strong associations and explained 35% of the variability present in the satisfaction variable: more pain relief received, higher allowed participation in pain treatment decisions, and no desire to have received more pain treatment. Patient factors and additional IPO items reflecting pain experience (eg, worst pain intensity), pain-related impairment, and information on pain treatment added little explanatory value, partially due to covariate correlations. Effects were highly consistent across centres and countries. We conclude that satisfaction with postoperative pain treatment is associated with the patients' actual pain experience, but more strongly with impressions of improvement and appropriateness of care. To the degree they desire, patients should be provided with information and involved in pain treatment decisions.

The initial development of PAIN OUT has been achieved. From 2013, it continues as a not-for-profit academic project, open to clinicians and researchers worldwide. The International Association for Study of Pain and PAIN OUT will work together to maintain, disseminate and develop the registry.

The current state of postoperative pain therapy leaves much room for improvement. Quality indicators in the field of acute pain medicine might help improve patient care.