Disparities and reverse disparities in HPV vaccination: A systematic review and meta-analysis

Studies disagree about whether racial and ethnic groups have lower or higher human papillomavirus (HPV) vaccination uptake, an important issue given large disparities in some HPV cancers. We sought to characterize and explain racial and ethnic differences in HPV vaccination. We systematically searched PubMed, CINAHL, Embase, and Web of Science to identify US studies through mid-2017 reporting associations of race and ethnicity with HPV vaccination. We identified 118 studies (n=3,095,486) published in English that reported HPV vaccine initiation or follow-through in the US from which we could calculate effect sizes. We used random effects meta-analysis to synthesize effect sizes for comparisons of Whites or non-Hispanics to Blacks, Hispanics, Asians, or all minority groups combined. Studies showed no racial or ethnic differences in HPV vaccine initiation overall. However, when restricting to studies using provider-verified vaccination data, minorities were 6.1% [3.3%-8.8%] more likely than Whites to initiate HPV vaccination. Advantages were larger for Hispanics, males, and younger samples (age<18). In contrast, minorities were 8.6% [5.6%, 11.7%], less likely than Whites to follow-through with the full HPV vaccine series, a disparity present across all participant and study characteristics. More recent studies found larger advantages for racial and ethnic minorities in HPV vaccine initiation and smaller disparities in follow-through. In summary, high-quality studies found racial and ethnic minorities are more likely to initiate but less likely to follow-through with HPV vaccination, a clear finding that self-report studies obscure. Higher HPV vaccine initiation among minorities suggests potential reductions in HPV cancer disparities.