This can be performed in a blinded double dummy study, which is very difficult to design.
The trial was a 12-week multicentre, randomised, double-blind, double dummy study; 419 patients with moderate/severe COPD were randomised to BDP/FF 200/12 μg or FP/S 500/50 μg twice daily.
5. Baldari U, Righini MG, Raccagni AA, et al. Comparative double blind, double dummy study on the efficacy and safety of fluconazole 100 mg/day versus terbinafine 250 mg/day in the treatment of dermatomycoses.
In multivariable analyses, results were adjusted on all baseline characteristic variables which differed between the two studies, and a dummy variable for study was used to account for additional differing baseline risks between the two cohorts.
In a double-blind, double-dummy study, patients were randomly assigned in a 1 1 ratio to receive ticagrelor and placebo (180-mg loading dose followed by 90 mg twice a day) or to receive clopidogrel and placebo (300- to 600-mg loading dose or continuation with a maintenance dose followed by 75 mg per day) for 6 to 12 months.
The circles with squares around them, 30 in number, in Figure 5B indicate dummy studies invented by the trim and fill method to counteract bias.
The plot clearly shows that small negative studies are under-represented (fewer circles towards the bottom right of the graph in Figure 5A) and the use of the dummy studies to compensate for this deficiency.
Trial 0021 was a double-blind, double-dummy study conducted in North America.
A double-blind, double-dummy study design was used to conceal the identity of treatments by use of study drugs and respective matching placebos that were all identical in packaging, labelling, schedule of administration, and appearance.
This was evaluated in the recent Apixaban for the Prevention of Stroke in Subjects with Atrial Fibrillation (ARISTOTLE) trial where apixaban was compared to warfarin in intermediate- to high-risk AF patients in a double-blind, double-dummy study conducted at 1034 sites in 39 countries.
