Practical considerations
The COR Tool is not intended to replace currently available ROB assessment tools, but rather, is intended to be used alongside these tools, to assess the completeness of outcome reporting in any trial. ROB tools tend to focus on study design, conduct and analysis, placing emphasis on identifying aspects that may lead to bias. For example, the six domains assessed in the Cochrane ROB tool are (1) random sequence generation, (2) allocation concealment, (3) blinding of participants and personnel, (4) blinding of outcome assessment, (5) incomplete outcome data, and (6) selective reporting – none of which directly assess the comprehensiveness of the outcomes that are chosen to be measured.12 To address bias related to outcome reporting, Cochrane recommends the use of COS, introduced by the Core Outcome Measures in Effectiveness Trials (COMET) initiative in 2012,27 and endorsed by the Core Outcomes in Women’s and Newborn Health (CrOWN) group.32 By creating standards for reporting, COS are effective at facilitating more applicable and transparent comparisons between interventions and across studies, an important of ensuring standardization of outcomes across studies.33 However, the focus on ensuring a ‘core’ or ‘minimum’ set of outcomes, becomes a barrier to ensuring comprehensiveness of outcome reporting, as we have recently shown. Utilizing the COR Tool in conjunction with COS would ensure that all relevant outcome areas are covered while still ensuring the interests of all stakeholders are considered in current health research.