All respondents were contacted via Random Digit
Cell phones numbers are selected using random digit
DESIGN: The Menopause Epidemiology Study is a cross-sectional, population-based study of women 40 to 65 years old in the United States chosen from a source population selected by random digit
dialing and probability sampling.
However, on most research conducted via the telephone, telephone numbers are generated using a process known as 'random digit
We acknowledge that a "bank" of these readily accessible controls could permit more rapid recruitment of participants in numerous age strata and obviate the need for extensive random digit
dialing to recruit an adequate age-matched control population in many investigations.
The National Household Education Surveys Program (NHES) includes a series of random digit
dial (RDD) surveys developed by the National Center for Education Statistics (NCES) in the Institute of Education Sciences, U.S.
Earlier in the year, Manhattan Research conducted a similar random digit
dial telephone survey of 1,208 U.S.
All data were collected by the Gallup Organization, using telephone interviews based on identical random digit
dialing sampling methods.
It cautions, however, that the ratings are not readily comparable with those that preceded them because the latest poll has adopted a new polling method known as random digit
dialing, as opposed to the older one based on phone directories.
comScore will continue to maintain Media Metrix' North American consumer panel and its Random Digit
Dial (RDD) sample design.
Drivers in two commuter van pools performed two subsidiary tasks - delayed digit recall and random digit
generation - while traveling a mix of rural secondary roads, limited access expressways, high-density urban drives, and downtown city streets on a daily commute from upstate New York to New York City.