Community health workers can boost screening mammography compliance with stronger effects in several specific situations, including when employed in urban settings and when the community health worker and patients are racially or ethnically concordant, according to a meta-analysis published June in Cancer Epidemiology, Biomarkers & Prevention.
Although early detection of breast cancer can reduce mortality and improve survival, women who belong to ethnic or racial minorities, lack comprehensive health insurance or a usual source of medical care, are non-English speakers, are immigrants, live in rural areas or are socioeconomically disadvantaged are less likely to adhere to screening mammography guidelines.
The community health worker (CHW) model employs lay individuals as liaisons to promote breast cancer screening among low-income, medically underserved, racial/ethnic minority and hard-to-reach populations.
To better evaluate the effectiveness of such programs, Kristin J. Wells, PhD, MPH, of the University of South Florida in Tampa, Fla., and colleagues completed a systematic review to synthesize evidence from all prospective controlled studies on the topic.
The researchers selected receipt of mammography screening as the primary outcome variable and abstracted it from each study. Ultimately, 18 studies enrolling 26,660 participants met the authors’ inclusion criteria for meta-analysis.
“Participation in a CHW intervention was associated with a statistically significant increase in receipt of screening mammography,” Wells and colleagues reported. The risk ratio (RR) favoring intervention reached 1.06.
The authors noted higher risk ratio associated with several factors. Specifically, when women were recruited from medical settings, the RR was 1.41. For programs conducted in urban settings, the RR was 1.23. Finally, programs that matched CHWs to participants’ race or ethnicity had an RR of 1.58.
Study design played a role as well, with randomized controlled trials showing a significant increase in screening rates. This effect was not observed in quasi-experimental studies, which showed both positive and negative effects. “These findings point out inherent biases associated with observational study designs,” the authors wrote.
Wells and colleagues noted several areas for future research. For example, “CHW interventions were associated with increases in rates of screening mammography in studies with routine care or health education but not in studies with mammography reminders.”
However, previous data have suggested that reminders can impact mammography rates, leading the authors to call for research “to determine the components of CHW interventions most strongly associated with increases in screening mammography to improve efficiency of CHW programs.”
They also stressed the need to evaluate the efficacy of CHW programs in increasing repeated mammography compliance, adding that “[future] research should be conducted to definitively determine which participants and populations benefit most from CHW interventions and why.”