tailieunhanh - IELTS Academic Reading Sample 92 - Try It and See

Với mong muốn giúp các bạn đạt kết quả cao trong kì thi, đã sưu tầm và chọn lọc gửi đến các bạn IELTS Academic Reading Sample 92 - Try It and See. Mời các bạn cùng tham khảo! | TRY IT AND SEE In the social sciences it is often supposed that there can be no such thing as a controlled experiment. Think again. A In the scientific pecking order social scientists are usually looked down on by their peers in the natural sciences. Natural scientists do experiments to test their theories or if they cannot they try to look for natural phenomena that can act in lieu of experiments. Social scientists it is widely thought do not subject their own hypotheses to any such rigorous treatment. Worse they peddle their untested hypotheses to governments and try to get them turned into policies. B Governments require sellers of new medicines to demonstrate their safety and effectiveness. The accepted gold standard of evidence is a randomised control trial in which a new drug is compared with the best existing therapy or with a placebo if no treatment is available . Patients are assigned to one arm or the other of such a study at random ensuring that the only difference between the two groups is the new treatment. The best studies also ensure that neither patient nor physician knows which patient is allocated to which therapy. Drug trials must also include enough patients to make it unlikely that chance alone may determine the result. C But few education programmes or social initiatives are evaluated in carefully conducted studies prior to their introduction. A case in point is the whole-language approach to reading which swept much of the English-speaking world in the 1970s and 1980s. The whole-language theory holds that children learn to read best by absorbing contextual clues from texts not by breaking individual words into their component parts and reassembling them a method known as phonics . Unfortunately the educational theorists who pushed the whole-language notion so successfully did not wait for evidence from controlled randomised trials before advancing their claims. Had they done so they might have concluded as did an analysis of 52 randomised .