Key points are not available for this paper at this time.
Dennis Slone, Leonard F. Gaetano, Leslie Lipworth, Samuel Shapiro, George Parker Lewis, Hershel Jick, Computer Analysis of Epidemiologic Data on Effect of Drugs on Hospital Patients, Public Health Reports (1896-1970), Vol. 84, No. 1 (Jan., 1969), pp. 39-52
Slone et al. (Wed,) studied this question.