© 1985 Oxford University Press
research-article |
Control-Initiated Case-Control Studies
Division of Epidemiology, UCLA School of Public Health Los Angeles, California 90024, USA
Greenland S (Division of Epidemiology, UCLA School of Public Health, Los Angeles, California 90024, USA). Control-initiated case-control studies. International Journal of Epidemiology 1985, 14: 130134.
In a control-initiated study the investigator begins with existing data on a non-diseased group and then selects cases to obtain comparison data; thus the usual order of case and control selection is reversed. This paper discusses the parallels and differences between control-initiated studies and more traditional case-control designs. Special attention is given to problems of selection bias and matching. A sample-size formula for control-initiated studies is also provided.
Revised 1 February 1984