Discussed in detail at the below mentioned link
Frazier and Mosteller assert that medical research could be improved by a move toward larger, simpler clinical trials of medical treatments. Currently, researchers collect far more background information on patients than is strictly required for their trials-substantially more than hospitals collect-thereby escalating costs of data collection, storage, and analysis. Although limiting information collection could increase the risk that researchers will overlook facts relevant to a study, Frazier and Mosteller contend that such risk, never entirely eliminable from research, would still be small in most studies. Only in research on entirely new treatments are new and unexpected variables likely to arise.
Frazier and Mosteller propose not only that researchers limit data collection on individual patients but also that researchers enroll more patients in clinical trials, thereby obtaining a more representative sample of the total population with the disease under study. Often researchers restrict study participation to patients who have no ailments besides those being studied. A treatment judged successful under these ideal conditions can then be evaluated under normal conditions. Broadening the range of trial participants, Frazier and Mosteller suggest, would enable researchers to evaluate a treatment's efficacy for diverse patients under various conditions and to evaluate its effectiveness for different patient subgroups. For example, the value of a treatment for a progressive disease may vary according to a patient's stage of disease. Patients' ages may also affect a treatment's efficacy.
According to the passage, Frazier and Mosteller believe which of the following about medical research?
A. It is seriously flawed as presently conducted because researchers overlook facts that are relevant to the subject of their research.
B. It tends to benefit certain subgroups of patients disproportionately.
C. It routinely reveals new variables in research on entirely new treatments.
D. It can be made more accurate by limiting the amount of information researchers collect.
E. It cannot be freed of the risk that significant variables may be overlooked.
The author mentions patients' ages primarily in order to
A. identify the most critical variable differentiating subgroups of patients
B. cast doubt on the advisability of implementing Frazier and Mosteller's proposals about medical research
C. indicate why progressive diseases may require different treatments at different stages
D. illustrate a point about the value of enrolling a wide range of patients in clinical trials
E. substantiate an argument about the problems inherent in enrolling large numbers of patients in clinical trials
The passage is primarily concerned with
A. identifying two practices in medical research that may affect the accuracy of clinical trials
B. describing aspects of medical research that tend to drive up costs
C. evaluating an analysis of certain shortcomings of current medical research practices
D. describing proposed changes to the ways in which clinical trials are conducted
E. explaining how medical researchers have traditionally conducted clinical trials and how such trials are likely to change