Refusals to Cooperate
There has been a good deal of recent research on this-both on the extent and effects of non-cooperation. The following are good summaries of this research:
Curtin, Richard; Presser, Stanley and Singer, Eleanor(2005). "Changes in Telephone Survey Nonresponse over the Past Quarter Century," Public Opinion Quarterly. 69:1, 87-99.
Groves, Robert; Dillman, Don; Eltinge, John; and Little, Roderick, editors (2001). Survey Nonresponse. New York: Wiley.