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Fig. 3 | BMC Medical Research Methodology

Fig. 3

From: Drug*placebo interaction effect may bias clinical trials interpretation: hybrid balanced placebo and randomized placebo-controlled design

Fig. 3

Time Course of Self-Reported Drowsiness and Mouth-dryness According to Intervention or Type of Effect. a to d mean unadjusted scores on continuous scale (a and b) and binary scale (c and d) per intervention. Squares indicate receiving 25 mg hydroxyzine, described as hydroxyzine (closed square with continuous line), as placebo (open square with interrupted line), or as unknown (closed square with dotted line). Circles indicate receiving placebo, described as placebo (closed circle with continuous line), as hydroxyzine (open circle with interrupted line), or as unknown (closed circle with dotted line). e and f mean adjusted scores per type of effect. Closed diamonds indicate total effect; closed squares interaction model-estimated drug effect, open squares conventionally estimated drug effect, and closed circle placebo effect. T-bars indicate standard errors

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