04/20/2004 - Faced with a growing number of unsolicited telephone calls and armed with increasingly sophisticated technology for screening their calls, more Americans are refusing to participate in telephone polls than was the case just six years ago. Yet a survey research experiment to gauge the effects of respondent cooperation on survey quality indicates that carefully conducted polls continue to obtain representative samples of the public and provide accurate data about the views and experiences of Americans.
A typical five-day survey conducted by the Pew Research Center, employing standard techniques used by most opinion polling organizations, now obtains interviews with people in fewer than three-in-ten sampled households (27%). That represents a decrease of about nine percentage points (on average) from the late 1990s.1 The decline results from increased reluctance to participate in surveys and not from an inability by survey organizations to contact someone in a household.
The growing use of answering machines, voice mail, caller ID, and call blocking is not preventing survey organizations from reaching an adult in most of the households sampled. Across five days of interviewing, surveys today are able to make some kind of contact with the vast majority of households (76%), and there is no decline in this contact rate over the past seven years. But because of busy schedules, skepticism and outright refusals, interviews were completed in just 38% of households that were reached using standard polling procedures. In 1997, a majority of those who were reached (58%) cooperated with the survey. The decline in cooperation also was seen in a separate survey, which had a much longer field period and used more rigorous survey techniques. In this poll, which was in the field for five months, 59% of contacted respondents cooperated, compared with 74% in 1997.
But the decline in participation has not undermined the validity of most surveys conducted by reputable polling organizations. When compared with benchmarks obtained from the U.S. Census and other government surveys with response rates that exceed 90%, the demographic and social composition of the samples in the average poll today is remarkably accurate.
Read the full report Polls Face Growing Resistance But Still Representative on the Pew Research Center for the People & the Press Web site.