Outcome domains and pain outcome measures in randomized controlled trials of interventions for postoperative pain in children and adolescents.

<bold>Background: </bold>We analysed outcome domains and pain outcome measures in randomized controlled trials of interventions for postoperative pain management in children and adolescents and compared them to the core outcome set recommended by the Pediatric Initiative on Methods, Measurement and Pain Assessment in Clinical Trials (PedIMMPACT).<bold>Methods: </bold>Systematic literature search was conducted in MEDLINE, CDSR, DARE, CINAHL and PsycINFO up to 31 January 2017. One author extracted data and second verified the extraction. Outcome domains and pain outcome measures were analysed and compared with the PedIMMPACT core outcome set.<bold>Results: </bold>We included 337 trials. Median number of reported outcomes was five (range 1-11) for the included trials and two (range 0-6) for PedIMMPACT. The most commonly analysed PedIMMPACT outcome domains were pain intensity (93%) and "symptoms and adverse events" (83%). The remaining four PedIMMPACT outcomes were present in under 30% of included randomized controlled trials. Proportion of PedIMMPACT outcome domains did not change after the PedIMMPACT was published in 2008. Of the 312 trials that reported pain intensity, 303 (97%) also specified pain assessment tools, in which the most common was the visual analogue scale (24%) followed by the Children's Hospital of Eastern Ontario Pain Scale (18%).<bold>Conclusion: </bold>Analysed trials about interventions for pediatric postoperative pain insufficiently used the recommended core outcome set for acute pain in children. Relevance of the PedIMMPACT core outcome set, as well as the reasons behind its limited uptake, need to be further evaluated.<bold>Significance: </bold>Recommended core outcomes have been insufficiently used in randomized controlled trials about postoperative pain in children, which hinders comparability of studies and makes synthesis of evidence difficult. [ABSTRACT FROM AUTHOR]