Analysis by intention to treat

Researchers assessed the effects of continuous positive airway pressure on blood pressure in patients with moderate to severe obstructive sleep apnoea and recently diagnosed but untreated systemic hypertension. Blood pressure was measured using 24 hour ambulatory monitoring. A double blind randomised controlled trial study design was used. Control treatment was sham continuous positive airway pressure delivered at a very low pressure. A total of 169 patients were assigned to continuous positive airway pressure and 171 to sham treatment.1 The primary outcome was the change at three months from baseline in mean 24 hour ambulatory blood pressure monitoring values. The analysis was undertaken by the …