Pragmatic trials: How to adjust for the 'Hawthorne effect'?

摘要

Hashimoto et al have conducted an interesting study to offer a practical and pragmatic insight into steroid-dependent asthma therapeutics in real-world practice. They proposed a strategy based on internet monitoring of objective (spirometry and fraction of exhaled nitric oxide) and subjective (asthma control and asthma-related quality of life questionnaires) measurements to adjust the dose of oral corticosteroids in patients with severe, uncontrolled asthma. However, how 'pragmatic' is a trial in which the patients have to sign an informed consent in order to participate in the study? Signing informed consents or receiving simple verbal instructions has been shown to significantly influence the outcome of interest in simple or more complicated studies.