Mc4 Improvement in Medication Adherence for Members Enrolled in a Zero Dollar Copay Program Is Sensitive to Socioeconomic Status: A Blue Cross Blue Shield of Louisiana Perspective

Abstract

A difference-in-difference-in-difference (DDD) model was used to compare the trends. Several sample populations were included in this study for different types of cancer screening. All states were analyzed in this study. States expanded Medicaid during the study period were regarded as the treatment group, otherwise, as a control group. Robustness checks were conducted after main analysis. Statistical analysis was conducted in Stata/SE 15.1 (StataCorp LLC, College Station, TX). Results: Medicaid expansion slightly improved screening rate by 2%, 0.3% and 2% respectively for breast cancer, cervical cancer and prostate cancer for respondents whose income were below or at 138 % federal poverty line (FPL) in expansion states comparing respondents whose income were over 138 % in non-expansion states. The screening rate for prostate cancer had a marginally significant improvement, increased by 4% comparing respondents with household income below or at 138 % FPL in expansion states with respondents with household income over 400 % FPL in non-expansion states. And these effects have disparities in different racial groups. Conclusions: The effect of Medicaid expansion on cancer screening was not significant for most cancer screening in this study and only marginally significant for prostate cancer when comparing respondents with household income below 138 % FPL in expansion states with respondents with household income over 400 % FPL in non-expansion states.