Identify whether the following study is an observational study or an experiment. If its an experiment identify the control group and treatment group and discuss whether a single or double blinding is necessary. If the study is observational state whether it is a case control study and if so identify cases and controls.
A double blind drug vs. placebo study of 109 patients suffering from tinnitus demonstrated the effectiveness of ginkgo biloba extract. The ginkgo treatment improved the condition of all patients.
- Observational study, not case control
- Experiment, the treatment group is patients that received the drug and the control group is patients that received the placebo, double blind
- Experiment, the control group is patients who received the drug and the control group is patients who received nothing, double blind
- Observational study, case control, the cases are the patients that received the drug the controls are the patients who received the placebo
An observational study or experiment is examined. The treatment group for patients that received the drug and the control group of patients that received the placebo is analyzed.