Medicaid, Medicare, and Commercial Insurance Studies| Volume 23, SUPPLEMENT 1, S6-S7, May 01, 2020

# MC1 THE EFFECT OF MEDICAID EXPANSION ON CANCER SCREENING RATE: A DIFFERENCE-IN-DIFFERENCE-IN-DIFFERENCE MODEL

Open Archive

## Objectives

This study aimed to evaluate if Medicaid expansion improved cancer screening, especially for prostate cancer, colorectal, breast and cervical cancer, comparing lower with higher household income among non-elderly adults.

## Methods

This study used the Behavior Risk Factor Surveillance System, a nationally representative health-related telephone survey, to compare cancer screening rates using surveys of 2012, 2014, 2016 and 2018 based on Medicaid expansion status. 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.