Yonsei Med J.  2018 Nov;59(9):1034-1040. 10.3349/ymj.2018.59.9.1034.

Socioeconomic Inequalities in Colorectal Cancer Screening in Korea, 2005–2015: After the Introduction of the National Cancer Screening Program

• Mai TT
• Lee YY
• Suh M
• Choi E
• Lee EY
• Ki M
• Cho H
• Park B
• Jun JK
• Kim Y
• Oh JK
• Choi KS

• KMID: 2422487
• DOI: http://doi.org/10.3349/ymj.2018.59.9.1034

Abstract

PURPOSE
This study aimed to investigate inequalities in colorectal cancer (CRC) screening rates in Korea and trends therein using the slope index of inequality (SII) and relative index of inequality (RII) across income and education groups.
MATERIALS AND METHODS
Data from the Korean National Cancer Screening Survey, an annually conducted, nationwide cross-sectional survey, were utilized. A total of 17174 men and women aged 50 to 74 years were included for analysis. Prior experience with CRC screening was defined as having either a fecal occult blood test within the past year or a lifetime colonoscopy. CRC screening rates and annual percentage changes (APCs) were evaluated. Then, SII and RII were calculated to assess inequality in CRC screening for each survey year.
RESULTS
CRC screening rates increased from 23.4% in 2005 to 50.9% in 2015 (APC, 7.8%; 95% CI, 6.0 to 9.6). Upward trends in CRC screening rates were observed for all age, education, and household income groups. Education inequalities were noted in 2009, 2014, and overall pooled estimates in both indices. Income inequalities were inconsistent among survey years, and overall estimates did not reach statistical significance.
CONCLUSION
Education inequalities in CRC screening among men and women aged 50 to 74 years were observed in Korea. No apparent pattern, however, was found for income inequalities. Further studies are needed to thoroughly outline socio-economic inequalities in CRC screening.

Keyword

Colorectal neoplasms; inequalities; socioeconomic factors; early detection of cancer

MeSH Terms

Colonoscopy
Colorectal Neoplasms*
Cross-Sectional Studies
Early Detection of Cancer*
Education
Family Characteristics
Female
Humans
Korea*
Male
Mass Screening*
Occult Blood
Socioeconomic Factors*

Figure

• 

  Fig. 1 Absolute and relative inequalities in CRC screening from 2005 to 2015. (A) Absolute educational inequalities in CRC screening rates. (B) Absolute household income inequalities in CRC screening rates. (C) Relative educational inequalities in CRC screening rates. (D) Relative household income inequalities in CRC screening rates. Solid line represents the line of equality; dotted line reflects pooled coefficients. CRC, colorectal cancer; SII, slope index of inequality; RII, relative index of inequality; CI, confidence interval.

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