Which of the following is not true about non-randomized trials?: (A) Approach of comparability is high, (B) Degree of comparability is high, (C) The experiment can serve as its own control or can utilize a natural control, (D) Several trials may be needed before evaluation is considered conclusive
Answer is B. Non-randomized trials ( i.e. Those depaing from strict randomization for practical purposes but in such a manner that non-randomization does not seriously affect the theoretical basis of conclusions ( refer pg 81, park 23 rd edition)