Standard Article

Random Digit Dialing Sampling for Case–Control Studies

  1. Joseph Waksberg

Published Online: 15 JUL 2005

DOI: 10.1002/0470011815.b2a03106

Encyclopedia of Biostatistics

Encyclopedia of Biostatistics

How to Cite

Waksberg, J. 2005. Random Digit Dialing Sampling for Case–Control Studies. Encyclopedia of Biostatistics. 6.

Author Information

  1. Westat, Rockville, MD, USA

Publication History

  1. Published Online: 15 JUL 2005


Random digit dialing (RDD) is a useful tool in epidemiological research, particularly for selecting controls in population-based case–control studies. The paper discusses the two principal methods currently used for sample selection in RDD, and indicates why other, possibly simple methods, are unsatisfactory. The principal considerations that should be taken into account in determining the details of a sample selection method (e.g. geographical boundaries of cases and controls, whether to choose more than one control per household, response rates, etc.) are described. Issues relating to data collection, once the sample has been selected, are also described including how these follow-up activities could influence the choice of sample design and could complicate the methods of analysis of the study results.


  • random digit dialing;
  • telephone sampling;
  • case–control studies;
  • selecting controls