I ndividuals affected by immune-mediated inflammatory diseases (referred to hereafter as immune-mediated diseases), such as inflammatory bowel disease, multiple sclerosis and rheumatoid arthritis, share an increased risk for influenza and related complications; 1 therefore, prevention of influenza is important. Effective implementation of influenza vaccination strategies requires knowledge of vaccine uptake or use among target populations. However, our understanding of influenza vaccine uptake in populations with immune-mediated diseases has been limited by studies with small sample sizes, selection bias, cross-sectional designs, variable study durations and variable study periods. Prior findings regarding vaccine uptake among persons with immune-mediated diseases have been highly variable. 2-5 A