Objective: The impact of worksite intervention studies is maximized when reach and enrollment are high and attrition is low. Differences in reach, enrollment, and retention were investigated by comparing 2 different employee recruitment methods for a home-based cancer-prevention intervention study.
Methods: Twenty-two worksites (N = 10,014 employees) chose either active or passive methods to recruit employees into a home-based intervention study. Reach (e.g., number of employees who gave permission to be called at home), Enrollment (e.g., number of employees who joined the home intervention study), and Attrition (e.g., number who did not complete the 12- and 24-month follow-ups) were determined. Analysis at the cluster level assessed differences between worksites that selected active (n = 12) versus passive (n = 10) recruitment methods on key outcomes of interest. Employees recruited by passive methods had significantly higher reach (74.5% vs. 24.4% for active) but significantly lower enrollment (41% vs. 78%) and retention (54% vs. 70%) rates (all ps < .0001). Passive methods also successfully enrolled a more diverse, high-risk employee sample. Passive (vs. active) recruitment methods hold advantages for increased reach and the ability to retain a more representative employee sample. Implications of these results for the design of future worksite studies that involve multilevel recruitment methods are discussed.