Abbott, E. A. (1884). Flatland: A Romance of Many Dimensions. London: Seeley & Company.
Allard, R., and Boivin, J.-F. (2007). Using causal models to show the effect of untestable assumptions on effect estimates in randomized controlled trials. Clinical Trials, 4, 611–620.
Al-Shahi, R., Vousden, C., and Warlow, C. (2005). Bias from requiring explicit consent from all participants in observational research: prospective population based study. British Medical Journal, 331, 942–947.
Amery, W., and Dony, J. (1975). A clinical trial design avoiding undue placebo treatment. Journal of Clinical Pharmacology, 10, 674–679.
Anderson, S., Auquier, A., Hauck, W., Oakes, D., Vandaele, W., and Weisberg, H. (1980). Statistical Methods for Comparative Studies. New York: John Wiley & Sons.
Angrist, J. D., Imbens, G. W., and Rubin, D. B. (1996). Identification of causal effects using instrumental variables (with discussion). Journal of the American Statistical Association, 91, 444–472.
Antithrombotic Trialists Collaboration (ATT). (2009). Aspirin in the primary prevention of vascular disease: collaborative meta-analysis of individual participant data from randomised trials. Lancet, 373, 1849–1860.
Austin, P. C. (2008). A critical appraisal of propensity-score matching in the medical literature (with discussion). Statistics in Medicine, 27, 2037–2049.
Baldus, D. C., Woodworth, G. G., and Pulaski, C. A. (1990). Equal Justice and the Death Penalty: A Legal and Empirical Analysis. Boston: ...