Bias in analytic research

Publisher Summary This chapter focuses on the bias in analytic research. Case-control studies are attractive. They can be executed quickly and at low cost, even when the disorders of interest are rare. The execution of pilot case-control studies is becoming automated; strategies have been devised for the “computer scanning” of large files of hospital admission diagnoses and prior drug exposures, with detailed analyses carried out in the same data set on an ad hoc basis. As evidence of their growing popularity, when one original article was randomly selected from each issue of The New England Journal of Medicine, The Lancet, and the Journal of the American Medical Association for the years 1956, 1966, and 1976, the proportion that reported case-control analytic studies increased fourfold over these two decades; however, the proportion reporting cohort analytic studies fell by half; a general trend toward fewer study subjects but more study authors was also noted.