When the Cochrane Collaboration (discussed on page 537) was first getting started, a report in New Scientist (Vine, 21 January 1995), announced that the UK Cochrane Centre in Oxford would be launching the Cochrane Database of Systematic Reviews, which will “focus on a number of diseases, drawing conclusions about which treatments work and which do not from all the available randomized controlled trials” (p. 14).
a. Why do you think they only planned to include “randomized controlled trials” (that is, randomized experiments) and not observational studies?
b. Do you think they should include studies that did not find statistically significant results when they do their meta- analyses? Why or why not?