Allocation of study medication
Background information
A "randomized" and "blinded" allocation of patients to one of the three treatment groups (low starting dosage, high starting dosage, placebo) is necessary for unbiased study results.
"Randomized" means that patients are assigned to a group in a random manner. This procedure precludes practitioners from choosing the treatment according specific patient characteristics, such as their age or disease severity.
In this context, "blinded" means that neither the patient nor the practitioner know which group the patient has been allocated to. With regard to patient safety, the group allocation for every study participant is placed in a sealed envelope that can be opened only under certain circumstances.
Imagine that a patient was aware of his/her group allocation, but would prefer another treatment group. This knowledge could affect the patient’s motivation for further study participation or for the intake of medication, and could hence jeopardize the success of the study. Or a practitioner who definitely knows that his/her patient is receiving a placebo might prescribe additional therapy.
Without randomization and blinding, the results of the study would be determined by a broad range of individual factors. These mandatory procedures in clinical trials, however, guarantee that study results are solely attributable to the efficacy of the medication under study.
Procedure in the CORRA study
Each practice participating in the CORRA study has study medication in stock for all three treatment groups (low starting dosage, high starting dosage, placebo). One package includes the medication for one person and is assigned to one of the three treatment groups. It is impossible to recognize group allocation based on the package exterior. At the beginning of the treatment phase, the rheumatologist in charge hands out the medication package randomly assigned to the patient.
Each package contains twelve blisters with seven capsules each, for intake of one capsule a day over twelve weeks of intervention. The content of each package with regard to diameter, shape, color, and taste is identical for all three groups. Therefore, neither the practitioner nor the patient are able to guess which group the patient has been assigned to. However, if patient safety requires, information on the patient's group allocation can be obtained easily at any time.
The figure below provides an overview of the dosages of study medication in the three treatment groups.