The purpose of double blinding in clinical trials is to?: (A) Achieve comparability between study and control groups, (B) Avoid observer bias, (C) Avoid subject bias, (D) Avoid observer and subject bias
Answer is D. Ans. is 'd' i.e., Avoid observer and subject bias Double blinding ensures that both the observer and subject are unaware of the group allocation and treatment. It there by eliminates both subject bias and the observer bias.