Pre-recruited panel surveys
Pre-recruited panel surveys are, generally
speaking, groups of individuals who have
agreed in advance to participate in a series of
surveys. For Internet-based surveys requiring
probability samples, these individuals are
generally recruited via some means other than
the web or e-mail – most often by telephone
or postal mail.
For a longitudinal effort consisting of a
series of surveys, researchers may recruitpanel members specifically for that effort. For
smaller efforts or for single surveys, a number
of companies maintain panels of individuals,
pre-recruited via a probability-based sampling
methodology, from which sub-samples can
be drawn according to a researcher’s speci-
fication. Knowledge Networks, for example,
recruits all of its panel members via telephone
using RDD, and it provides equipment and
Internet access to those that do not have
it in an attempt to maintain a panel that
is a statistically valid cross section of the
population (see Pineau and Dennis, 2004, for
additional detail).
Pre-recruited, Internet-enabled panels can
provide the speed of Internet-based surveys
while simultaneously eliminating the
often-lengthy recruitment process normally
required. As such, they can be an attractive
option to researchers who desire to field
an Internet-based survey, but who require a
sample that can be generalized to populations
outside of the Internet-user community.
However, pre-recruited panels are not
without their potential drawbacks. In particular,
researchers should be aware that
long-term panel participants may respond
differently to surveys and survey questions
than first-time participants (called ‘panel
conditioning’ or ‘time-in-sample bias’). Also,
nonresponse can be an issue if the combined
loss of potential respondents throughout all
of the recruitment and participation stages
is significant. However, as Couper (2000)
concludes, ‘… in theory at least, this approach
begins with a probability sample of the
full (telephone) population, and assuming no
nonresponse error permits inference to the
population…’.