Proactive versus reactive recruitment to a physical activity intervention for breast cancer survivors: Does it matter?

Background There is a gap in the current breast cancer survivorship literature identifying potential sample biases that may result from recruiting participants via different methods.Purpose To document whether participant recruitment method influences baseline demographic or psychosocial variables and trial participation among breast cancer survivors recruited for a physical activity intervention trial.Methods Participants were recruited for the trial via either a reactive method (letters mailed through their oncologist’s office inviting them to contact the research staff) or a proactive method (referred in person by their oncologist at a clinic appointment). The groups of participants recruited via the two methods were compared based on baseline sociodemographic characteristics, weight, time since diagnosis, stage of disease, treatment, motivational readiness for physical activity, level of physical activity, self-reported physical and mental health, willingness to receive the intervention, and study retention.Results Participants recruited proactively were closer to the point of diagnosis (mean = 2.5 years, standard deviation (SD) = 1.9 years) than participants recruited reactively via letter mailings (mean = 3.4 years, SD = 2.3 years; p < .05). The two groups were similar with respect to all other baseline characteristics and retention.Limitations Recruitment via the two methods was not concurrent. Also, proactive recruitment occurred at a single hospital site. Mailings were made by the oncologists; we are unable to estimate how many letters were mailed. Similarly, we have no information for the patients who were not referred to the study during proactive recruitment.Conclusions Despite the potential for differences in characteristics and degree of trial participation between trial participants recruited proactively and reactively, in this investigation, the two groups were similar. Information from other trials in other conditions may confirm or modify our conclusion.