Russel-Research-Method-in-Anthropology

236 Chapter 9
the groups was homogeneous with respect to certain independent variables—
again, just as we saw with respect to experimental and sampling design.
The principle of factorial design is an essential part of focus group methodology.
The study by Knodel et al. (1984) on page 234 is an example of
factorial design: two age groups and two genders, for a total of four groups
(men under 35 and women under 30, who wanted three or fewer children, and
men over 50 and women over 50, who had at least five children), repeated in
six venues across Thailand, for a total of 24 groups.
Are Focus Groups Valid?
Ward et al. (1991) compared focus group and survey data from three studies
of voluntary sterilization (tubal ligation or vasectomy) in Guatemala, Honduras,
and Zaire. Ward et al. report that, ‘‘Overall, for 28% of the variables the
results were similar’’ in the focus group and survey data. ‘‘For 42% the results
were similar but focus groups provided additional detail; for 17% the results
were similar, but the survey provided more detail. And in only 12% of the
variables were the results dissimilar’’ (p. 273).
In the Guatemala study, 97% of the women surveyed reported no regrets
with their decision to have a tubal ligation. The ‘‘vast majority’’ of women in
the focus groups also reported no regrets. This was counted as a ‘‘similar
result.’’ Ten percent of the women surveyed reported having had a tubal ligation
for health reasons. In the focus groups, too, just a few women reported
health factors in their decision to have the operation, but they provided more
detail and context, citing such things as complications from previous pregnancies.
This is an example of where the focus group and survey provide similar
results, but where the focus group offers more detail. Data from the focus
groups and the survey confirm that women heard about the operation from
similar sources, but the survey shows that 40% of the women heard about it
from a sterilized woman, 26% heard about it from a health professional, and
so on. Here, the survey provides more detail, though both methods produce
similar conclusions.
In general, though, focus groups—like participant observation, in-depth
interviews, and other systematic qualitative methods—should be used for the
collection of data about content and process and should not be relied on for
collecting data about personal attributes or for estimating population parameters
of personal attributes. The belief that a woman has or does not have a
right to an abortion is a personal attribute, like gender, age, annual income, or
religion. If you want to estimate the proportion of people in a population who