NCR has added some information on the research methodology for their recent study of American Catholics.

All data were collected by the Gallup Organization, using telephone interviews based on identical random digit dialing sampling methods. The sample size in 1987 was 803, and it included persons 18 or older in noninstitutionalized settings who said she or he was Catholic.

The 1993 sample was 802, sampled in the identical manner. The 1999 sample was slightly larger — 877 persons, of whom 12 percent were Hispanic. The 2005 sample was 875, of whom 15 percent were Hispanic.