As a result, telephone interviewing can allow for a much more exhaustive sample. The cost savings of conducting telephone research has been estimated at fifty to seventy-five percent of face-to-face interviews (Marcus & Crane, 1986; Worth & Tierney, 1993). Research conducted in 1979 (Groves & Kahn, 1979) was converted to 2001 dollars (D. C. Miller & Salkind, 2003) and this research showed a savings of 45% between telephone and personal interviews.