ABSTRACT Background Outcome measurement instruments (OMIs) are important for evaluating intervention effectiveness and quality. However, adopting OMIs remains challenging. This study aimed to select OMIs for a core outcome set (COS) for use in studies focusing on adherence to appropriate polypharmacy in older people. Methods A list of OMIs for COS outcomes and their feasibility information was compiled from the literature to select one OMI per outcome. Two rounds of Delphi questionnaires containing a range of OMIs were distributed to experts academics, healthcare professionals (HCPs), journal editors and methodologists who were asked to select OMIs for a subsequent consensus meeting using ‘Yes’, ‘No’, or ‘Uncertain’. The Delphi results were discussed and OMIs were voted on (Yes: important and No: unimportant) in a consensus meeting with experts and an interview with a public member. An OMI was included if ≥ 80% of participants voted on it as critical and ≤ 20% voted it as unimportant. Results Twenty‐one OMIs were presented to experts (Round 1, n = 42; Round 2, n = 39) in the Delphi exercise to achieve consensus on nine OMIs. Following the consensus meeting and interview (experts, n = 5; public participants, n = 1), agreement was achieved to select four OMIs: the Adherence to Refills and Medications Scale (ARMS, 100%); Multimorbidity Treatment Burden Questionnaire (MTBQ, 100%); Medication‐Related Burden Quality of Life questionnaire (MRB‐QoL, 83.3%); and ‘the number of undesired consequences of the intervention that result from administering multiple medications in older people (83.3%)’ for measuring medication adherence across multiple medications (subjective); treatment burden; health‐related quality of life (HRQoL) and adverse events and side effects (AEs and SEs), respectively. No agreement was reached regarding cost‐effectiveness and healthcare utilization. Conclusion This study selected OMIs for use with a COS in studies to improve adherence to appropriate polypharmacy in older people. Future research should identify appropriate OMIs for the remaining outcomes.
Shaker et al. (Thu,) studied this question.