Introduction: Persistent disparities in influenza vaccination rates exist between racial/ethnic minorities and Whites. The mechanisms that define this relationship are under-researched.
Objectives: (1) To evaluate racial/ethnic disparities in influenza vaccination and (2) to assess the mediating effects of barriers to influenza vaccination on the relationship between race/ethnicity and receipt of influenza vaccination.
Methods: Surveys assessing barriers to vaccination were administered to outpatients in a rural medical center in Southeastern Louisiana. Survey responses were matched to patient medical records. Likert-style statements were used to measure barriers to vaccination.. A mediation analysis assessing the relationship between race and influenza vaccination mediated by vaccination barriers was conducted.
Results: The self-reported influenza vaccination rate in those surveyed was 40.4%. Whites (45.5%) were more likely than racial/ethnic minorities (36.3%) to report receipt of an influenza vaccination (p=0.02). Racial/ethnic minorities reported significantly higher vaccination barrier scores (p<0.01). The relationship between race/ethnicity and vaccination was mediated by vaccination barriers, when controlling for provider recommendation and having at least one comorbid medical condition (natural indirect effect [NIE] p-value=0.02, proportion mediated=0.71).
Conclusions: Barriers to vaccination mediates the relationship between race/ethnicity and vaccination status. Providers should focus on minimizing fears that the vaccine will cause illness and emphasize that the vaccine is safe and effective at preventing severe influenza-associated illness. Additional efforts should be made to improve accessibility of the influenza vaccine, including addressing costs of vaccination and expanding the number and types of settings where the vaccine is offered.
2. Centers for Disease Control and Prevention. Estimates of death associated with seasonal influenza – United States 1976-2007. MMWR Morb and Mort Wkly Report 2010; 59:1057-62.
3. Thompson WW, Shay DK, Weintraub E, et al. Influenza-associated hospitalizations in the united states. JAMA. 2004; 292:1333-40.
4. Rolfes MA, Foppa IM, Garg S, Flannery B, Brammer L, Singleton JA, et al. Annual estimates of the burden of seasonal influenza in the United States: A tool for strengthening influenza surveillance and preparedness. Influenza and other respiratory viruses. 2018; 12:132-7.
5. Centers for Disease Control and Prevention. Flu Vaccination Coverage, United States, 2016-17 Influenza Season. 2017 [updated September 28, 2017; cited 2019 November 19]; Available from: https://www.cdc.gov/flu/fluvaxview/coverage-1617estimates.htm.
6. Centers for Disease Control and Prevention. Flu Vaccination Coverage, United States, 2013-14 Influenza Season. 2014 [cited 2017 February 6]; Available from: http://www.cdc.gov/flu/fluvaxview/coverage-1314estimates.htm.
7. Centers for Disease Control and Prevention. Flu Vaccination Coverage, United States, 2012-13 Influenza Season. 2013 [cited 2017 February 6]; Available from: http://www.cdc.gov/flu/fluvaxview/coverage-1213estimates.htm.
8. McIntyre AF, Gonzalez-Feliciano, A. G., Bryan, L. N., Santibanez, T. A., Williams, W. W., & Singelton, J. A. . Seasonal Influenza Vaccination Coverage —United States, 2009–10 and 2010–11. MMWR. 2013; 62:60-70.
9. Centers for Disease Control and Prevention. Flu Vaccination Coverage, United States, 2014-15 Influenza Season. 2015 [cited 2017 February 6]; Available from: https://www.cdc.gov/flu/fluvaxview/coverage-1415estimates.htm.
10. Bennett KJ, Bellinger JD, Probst JC. Receipt of Influenza and Pneumonia Vaccinations: The Dual Disparity of Rural Minorities. Journal of the American Geriatrics Society. 2010; 58:1896-902.
11. Fiscella K, Franks P, Doescher MP, Saver BG. Disparities in health care by race, ethnicity, and language among the insured: findings from a national sample. Medical care. 2002; 40:52-9.
12. Johnson DR, Nichol KL, Lipczynski K. Barriers to Adult Immunization. The American Journal of Medicine. 2008; 121:S28-S35.
13. Winston CA, Wortley PM, Lees KA. Factors Associated with Vaccination of Medicare Beneficiaries in Five U.S. Communities: Results from the Racial and Ethnic Adult Disparities in Immunization Initiative Survey, 2003. Journal of the American Geriatrics Society. 2006; 54:303-10.
14. Yousey-Hindes KM, Hadler JL. Neighborhood Socioeconomic Status and Influenza Hospitalizations Among Children: New Haven County, Connecticut, 2003–2010. American Journal of Public Health. 2011; 101:1785-9.
15. Bleser WK, Miranda PY, Jean-Jacques M. Racial/Ethnic Disparities in Influenza Vaccination of Chronically Ill US Adults: The Mediating Role of Perceived Discrimination in Health Care. Medical care. 2016; 54:570-7.
16. Hebert PL, Frick KD, Kane RL, McBean AM. The Causes of Racial and Ethnic Differences in Influenza Vaccination Rates among Elderly Medicare Beneficiaries. Health Services Research. 2005; 40:517-38.
17. Egede LE, Zheng D. Racial/Ethnic Differences in Influenza Vaccination Coverage in High-Risk Adults. American Journal of Public Health. 2003; 93:2074-8.
18. Armstrong K, Berlin M, Schwartz JS, Propert K, Ubel PA. Barriers to influenza immunization in a low-income urban population. American Journal of Preventive Medicine. 2001; 20:21-5.
19. Chen JY, Fox, S. A., Cantrell, C. H., Stockdale, S. E., & Kagawa-Singer, M. . Health desparities and prevention: racial/ethnic barriers to flu vaccinations. J Community Health. 2007; 32:5-20.
20. Frew PM, Painter JE, Hixson B, Kulb C, Moore K, del Rio C, et al. Factors mediating seasonal and influenza A (H1N1) vaccine acceptance among ethnically diverse populations in the urban south. Vaccine. 2012; 30:4200-8.
21. Zimmerman RK, Santibanez TA, Janosky JE, Fine MJ, Raymund M, Wilson SA, et al. What affects influenza vaccination rates among older patients? An analysis from inner-city, suburban, rural, and veterans affairs practices. The American Journal of Medicine. 2003; 114:31-8.
22. Wooten KG, Wortley PM, Singleton JA, Euler GL. Perceptions matter: Beliefs about influenza vaccine and vaccination behavior among elderly white, black and Hispanic Americans. Vaccine. 2012; 30:6927-34.
23. Sohn H. Racial and Ethnic Disparities in Health Insurance Coverage: Dynamics of Gaining and Losing Coverage over the Life-Course. Popul Res Policy Rev. 2017; 36:181-201.
24. Lu P-j, O'Halloran A, Williams WW. Impact of health insurance status on vaccination coverage among adult populations. American journal of preventive medicine. 2015; 48:647-61.
25. Fiscella K. Commentary--anatomy of racial disparity in influenza vaccination. Health services research. 2005; 40:539-49.
26. Fiscella K, Dressler R, Meldrum S, Holt K. Impact of influenza vaccination disparities on elderly mortality in the United States. Preventive Medicine. 2007; 45:83-7.
27. Logan J. Disparities in Influenza Immunization Among US Adults. Journal of the National Medical Association. 2009; 101:161-6.
28. U.S. Census Bureau PD. Annual Estimates of the Resident Population: April 1, 2010 to July 1, 2018. 2019 [cited 2020 February 7]; Available from: https://factfinder.census.gov/faces/tableservices/jsf/pages/productview.xhtml?src=bkmk.
29. Bennett KJ, Pumkam C, Probst JC. Rural–urban differences in the location of influenza vaccine administration. Vaccine. 2011; 29:5970-7.
30. Freimuth VS, Jamison AM, An J, Hancock GR, Quinn SC. Determinants of trust in the flu vaccine for African Americans and Whites. Social Science & Medicine. 2017; 193:70-9.
31. Lindley MC, Wortley PM, Winston CA, Bardenheier BH. The Role of Attitudes in Understanding Disparities in Adult Influenza Vaccination. American Journal of Preventive Medicine. 2006; 31:281-5.
32. Quinn SC. African American adults and seasonal influenza vaccination: Changing our approach can move the needle. Human Vaccines & Immunotherapeutics. 2018; 14:719-23.
33. Quinn SC, Jamison A, Freimuth VS, An J, Hancock GR, Musa D. Exploring racial influences on flu vaccine attitudes and behavior: Results of a national survey of White and African American adults. Vaccine. 2017; 35:1167-74.
34. Villacorta R, Sood N. Determinants of healthcare provider recommendations for influenza vaccinations. Preventive Medicine Reports. 2015; 2:355-70.
35. Cheney MK, John R. Underutilization of Influenza Vaccine: A Test of the Health Belief Model. SAGE Open. 2013; 3:2158244013484732.
36. Harris PA, Taylor R, Thielke R, Payne J, Gonzalez N, Conde JG. Research electronic data capture (REDCap)--a metadata-driven methodology and workflow process for providing translational research informatics support. J Biomed Inform. 2009; 42:377-81.
37. Centers for Disease Control and Prevention. Epidemiology and Prevention of Vaccine-Preventable Disease 2015.
38. Valeri L, VanderWeele TJ. Mediation analysis allowing for exposure–mediator interactions and causal interpretation: Theoretical assumptions and implementation with SAS and SPSS macros. Psychological Methods. 2013; 18:137-50.
39. Centers for Disease Control and Prevention. Flu Vaccination Coverage, United States, 2015-16 Influenza Season. 2016 [cited 2017 February 2]; Available from: https://www.cdc.gov/flu/fluvaxview/coverage-1516estimates.htm.
40. Centers for Disease Control and Prevention. Flu Vaccination Coverage, United States, 2018–19 Influenza Season. 2019 [updated September, 26 2019; cited 2019 November 1]; Available from: https://www.cdc.gov/flu/fluvaxview/coverage-1819estimates.htm#results.
41. Centers for Disease Control and Prevention. Estimates of Influenza Vaccination Coverage among Adults—United States, 2017–18 Flu Season. 2018 [cited 2020 January 1]; Available from: https://www.cdc.gov/flu/fluvaxview/coverage-1718estimates.htm.
42. Redelings MD, Piron J, Smith LV, Chan A, Heinzerling J, Sanchez KM, et al. Knowledge, attitudes, and beliefs about seasonal influenza and H1N1 vaccinations in a low-income, public health clinic population. Vaccine. 2012; 30:454-8.
43. Chapman GB, Coups EJ. Predictors of Influenza Vaccine Acceptance among Healthy Adults. Preventive Medicine. 1999; 29:249-62.
44. Baron RM, Kenny DA. The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations. Journal of personality and social psychology. 1986; 51:1173.
45. Hayes AF, Scharkow M. The Relative Trustworthiness of Inferential Tests of the Indirect Effect in Statistical Mediation Analysis: Does Method Really Matter? Psychological Science. 2013; 24:1918-27.
46. MacKinnon DP, Krull JL, Lockwood CM. Equivalence of the Mediation, Confounding and Suppression Effect. Prevention Science. 2000; 1:173-81.
47. Preacher KJ, Selig JP. Advantages of Monte Carlo Confidence Intervals for Indirect Effects. Communication Methods and Measures. 2012; 6:77-98.
48. Shrout PE, Bolger N. Mediation in experimental and nonexperimental studies: New procedures and recommendations. Psychological Methods. 2002; 7:422-45.
49. Zhao X, Lynch JG, Jr., Chen Q. Reconsidering Baron and Kenny: Myths and Truths about Mediation Analysis. Journal of Consumer Research. 2010; 37:197-206.
50. Hayes AF. Beyond Baron and Kenny: Statistical Mediation Analysis in the New Millennium. Communication Monographs. 2009; 76:408-20.
51. Kenny DA, Judd CM. Power Anomalies in Testing Mediation. Psychological Science. 2013; 25:334-9.
52. Rucker DD, Preacher KJ, Tormala ZL, Petty RE. Mediation Analysis in Social Psychology: Current Practices and New Recommendations. Social and Personality Psychology Compass. 2011; 5:359-71.
53. Maxwell SE, Cole DA. Bias in cross-sectional analyses of longitudinal mediation. Psychological Methods. 2007; 12:23-44.
54. Maxwell SE, Cole DA, Mitchell MA. Bias in Cross-Sectional Analyses of Longitudinal Mediation: Partial and Complete Mediation Under an Autoregressive Model. Multivariate Behavioral Research. 2011; 46:816-41.
55. Mitchell MA, Maxwell SE. A Comparison of the Cross-Sectional and Sequential Designs when Assessing Longitudinal Mediation. Multivariate Behavioral Research. 2013; 48:301-39.
56. Winer ES, Cervone D, Bryant J, McKinney C, Liu RT, Nadorff MR. Distinguishing Mediational Models and Analyses in Clinical Psychology: Atemporal Associations Do Not Imply Causation. Journal of Clinical Psychology. 2016; 72:947-55.