The Utility of Non-proportional Quota Sampling for Recruiting At-risk Women for Microbicide Research

Abstract

In the context of a measurement development study designed to contextualize microbicide acceptability, a sample that represented a range of at-risk women and maintained the statistical power needed for validity analyses was required. A non-proportional quota sampling strategy focused on race/ethnicity and number of sexual partners was utilized. This strategy resulted in enrollment of approximately equal proportions of Latina (31%), Black (36%), and White (32%) women, and an approximately 1:2 ratio of single-partnered (29%) and multi-partnered (71%) women. About 17% of women screened were ineligible based on eligibility criteria; an additional 16% were ineligible based on quota closures. Most participants were recruited through word of mouth (39%), communitybased organizations (19%), or media sources (19%). Women recruited through word of mouth had the highest screen-to-interview completion percentage (67%). Non-proportional quota sampling is a feasible option for ensuring adequate representation of sample characteristics in microbicide research, but this goal should be weighed against cost and staff burden.

Willingness to use microbicides varies by race/ethnicity, experience with prevention products, and partner type.

“…This sample contains women from lower socioeconomic strata and with limited education, likely a result of recruitment strategies that relied heavily on community-based organizations and word of mouth (Morrow et al, 2007). It will be imperative for researchers in other sociogeographic arenas to utilize the Willingness to Use Microbicides Scale with a clear understanding that language and sociopolitical culture will need to be accounted for and the scale re-evaluated.…”

“…As such, a non-proportional quota sampling strategy was employed. Details of recruitment procedures, including the effectiveness of nonproportional quota sampling procedures and community partnerships can be found in Morrow et al (2007). Nine hundred and twenty-two (922) women were screened for the study.…”

Cancers That U.S. Physicians Believe the HPV Vaccine Prevents: Findings from a Physician Survey, 2009

“…To ensure that adequate representation of targeted provider specialties was obtained, the 2009 DocStyles survey used quota sampling, a form of nonprobability sampling in which the proportions of selected participant characteristics within the sample are deliberately set. [10][11][12] The DocStyles survey has been used to explore a variety of topics, including chronic fatigue syndrome 13 and immunodeficiency diseases. 14 CDC licensed the results of the 2009 DocStyles survey from Porter Novelli (Washington, D.C.).…”

Measuring self-efficacy to use vaginal microbicides: the Microbicide Use Self-Efficacy instrument

“…A non-proportional quota sampling methodology was used to recruit subgroup strata based on race/ethnicity and number of vaginal sex partners in the past year. 31 …”