The GLORIA adherence subproject: problems and randomization mistakes

Medication adherence, which is the extent to which patients take their medication as prescribed, is essential in treating chronic inflammatory diseases such as rheumatoid arthritis (RA). Therefore, we nested a subproject in the two-year multicenter Glucocorticoid Low-dose Outcome in Rheumatoid Arthritis (GLORIA) trial to add a low-dose prednisolone (5 mg/day) or placebo to the standard care in older people (≥65 years) with RA. Adherence was measured with an electronic monitoring cap that recorded bottle openings in all patients. In the subproject, we performed an adherence intervention with an advanced cap that could communicate with an application on the smart device via Bluetooth. We randomized patients with a smart device to receive or not to receive adherence reminders on the smart device for three months. Multiple problems emerged that precluded an answer to the research question: sample size (overly optimistic estimates of older patients with a smart device), logistic issues (availability of smartcaps, data extraction), randomization and treatment allocation errors (despite training of personnel), and low quality of the data in the intervention group (hardware failure, discovered too late because data was read in batches). For future trials planning to include a subproject, we recommend keeping it simple, starting with a field test before the actual study starts, and monitoring data from the beginning of the study.