Modifiable influences on female HPV vaccine uptake at the clinic encounter level: a literature review

HPV vaccination and Native Americans: protocol for a systematic review of factors associated with HPV vaccine uptake among American Indians and Alaska Natives in the USA

INTRODUCTION

The nine-valent human papillomavirus (HPV) vaccine could prevent an estimated 92% of the cancers attributable to HPV types targeted by the vaccine. However, uptake of the HPV vaccine among American Indian and Alaska Native (AI/AN) adolescents has been low. AI/ANs also bear a disproportionate burden of cervical and other HPV-associated cancers. Increasing HPV vaccination rates is a national priority, but reviews and national surveys on HPV vaccination factors are lacking for the AI/AN population. The objective of this systematic review is to assess factors associated with HPV vaccination among AI/ANs in the USA.

METHODS AND ANALYSIS

A systematic review is proposed to synthesise the current literature on HPV vaccination factors in AI/ANs from 1 July 2006 until 30 September 2019. As applicable, controlled vocabulary terms, keywords and special features (eg, limits, explode and focus) will be incorporated into database searches. To maximise the identification of relevant studies, citation indexes and databases that index dissertations, preprints and grey literature are included. Studies will be screened and selected independently in two stages. In stage 1, titles and abstracts will be screened. In stage 2, full-text articles will be screened and selected. A data extraction form and quality assessment tool will be piloted, revised and implemented. If available, measures of frequency and association will be presented. A narrative synthesis of the included studies will also be undertaken and reported.

ETHICS AND DISSEMINATION

As our review will use publicly available data and publications, an Institutional Review Board review will not be required. We will disseminate the findings from this review through peer-reviewed publication(s) and conference presentation(s).

POTENTIAL AMENDMENTS

In the event of amendments to the protocol, we will provide the date, rationale, and description of the change for each amendment.

PROSPERO REGISTRATION NUMBER

CRD42020156865.

Factors associated with adolescent HPV vaccination in the U.S.: A systematic review of reviews and multilevel framework to inform intervention development

Multilevel factors impact HPV vaccine series initiation and completion among adolescents in the U.S. Synthesis of these factors is needed to inform intervention development and to direct future research. Current frameworks synthesizing factors focus on females only and do not include both series initiation and completion outcomes. We conducted a systematic review of reviews to identify modifiable individual-, provider-, and clinic-level factors associated with HPV vaccination outcomes among U.S. adolescents and developed a multilevel framework illustrating relations between factors to inform intervention development. We searched Medline, PsychInfo, Pubmed, CINAHL, and ERIC databases and included reviews published 2006 to July 2, 2018 describing individual-, provider-, or clinic-level factors quantitatively associated with HPV vaccination among U.S. adolescents. Two coders independently screened reviews, extracted data, and determined quality ratings. Sixteen reviews containing 481 unique primary studies met criteria. Factors synthesized into the multilevel framework included parent psychosocial factors (knowledge, beliefs, outcome expectations, intentions) and behaviors, provider recommendation, and patient-targeted and provider-targeted clinic systems. The scope of our framework and review advances research in two key ways. First, the framework illustrates salient modifiable factors at multiple levels on which to intervene to increase HPV vaccination. Second, the review identified critical gaps in the literature at each level. Future research should link the body of literature on parental intentions to vaccination outcomes, identify provider psychosocial factors associated with recommendation behaviors and subsequent vaccine uptake in their patient population, and understand clinic factors associated with successful implementation of patient- and provider-targeted system-level interventions.

Communication around HPV vaccination for adolescents in low- and middle-income countries: a systematic scoping overview of systematic reviews

BACKGROUND

Human papillomavirus (HPV) infection causes cervical cancer. More than 80% of those diagnosed with cervical cancer live in low- and middle-income countries (LMICs). The World Health Organization recommends vaccination as a public health measure against cervical cancer. Communication interventions are able to change how people think about vaccination and are thus instrumental in addressing vaccine hesitancy. Our aim was to provide a broad scoping overview of the available evidence on communication with adolescents, parents, and other stakeholders around HPV vaccination for adolescents, with a specific focus on LMICs.

METHODS

We conducted a systematic scoping overview of systematic reviews addressing a range of questions regarding communication around HPV vaccination. We considered reviews published between 2007 and 2018 focusing on communication around HPV vaccination and that searched for qualitative or quantitative studies for inclusion. We searched the Epistemonikos database which includes reviews from multiple electronic databases. Two overview authors screened titles and abstracts and examined potentially eligible reviews in full text. Data extraction was performed by one overview author and verified by a second. We assessed the reliability of the included reviews using an adapted version of AMSTAR 2.

RESULTS

We included twelve reviews in our overview. Four reviews assessed the effectiveness of communication interventions. These interventions intended to inform or educate about HPV and HPV vaccination, such as videos and fact sheets, or to remind or recall, such as text message reminders. Eight reviews assessed factors associated with HPV vaccination uptake, including communication-related factors such as whether the vaccine was recommended by a physician and people's knowledge regarding the vaccine. Nine reviews searched for studies from LMICs, but most found only a small number of studies from these countries.

CONCLUSIONS

The small number of studies identified from LMICs is of concern as these countries face the largest burden of disease related to HPV. This scoping overview also found and excluded a number of reviews because of important methodological limitations, highlighting the need for future reviews to use appropriate methods. The overview indicates areas in which further primary studies are needed on HPV vaccination communication in LMICs.

SYSTEMATIC REVIEW REGISTRATION

Open Science Framework https://osf.io/agzb4/.

Increasing Parental Knowledge Related to the Human Papillomavirus (HPV) Vaccine

INTRODUCTION

The purposes of this study were to evaluate parental attitudes toward general vaccination protocols and increase parental knowledge of the human papilloma virus (HPV) vaccine.

METHODS

A nonprobability convenience sample (N = 75) using a pre-/postintervention study design was conducted in a pediatric office in southern New Jersey. The Parental Attitudes Module measured the general disposition toward having children receive any type of vaccine. The HPV Knowledge Survey was a second tool used to specifically measures knowledge of the HPV vaccine. A self-directed computer-based learning was part of the educational intervention.

RESULTS

A paired t test showed that HPV Knowledge Survey postintervention scores were significantly higher than HPV Knowledge Survey preintervention scores (t = -10.585, p < .001). The Parental Attitudes Module and the HPV Knowledge Survey pretest showed a positive moderate relationship (r_s = .552, p < .001).

DISCUSSION

In the 10 years since the HPV vaccine has been on the market, there is a continued need to increase parental knowledge about the HPV vaccine to close the gap on vaccine nonadherence. A self-directed, computer-based learning tablet appears to be an effective tool to educate parents or legal guardians about the purpose, efficacy, and safety of the HPV vaccine.

Awareness of HPV and Uptake of Vaccination in a High-Risk Population

BACKGROUND

Immunization against the human papillomavirus (HPV) is effective at preventing HPV-related cancers, but vaccination rates have remained low. Levels of awareness could conceivably influence vaccination rates, but currently the relationship is unknown. This is the first study to test how strongly levels of awareness among parents and adolescents are related to subsequent HPV vaccination among a high-risk population of adolescents.

METHODS

This longitudinal cohort study measured baseline levels of awareness (about HPV, cervical cancer, HPV vaccination, and news or advertisements about HPV vaccination) among parents of adolescents and also a separate sample of adolescents. Participants resided in predominantly low-income, African American neighborhoods of a large American city. During a 12-month follow-up period, the outcome measures were defined as adolescent receipt of any HPV vaccination, as measured by clinic records.

RESULTS

Within 1 year, <16% of adolescents received vaccination. The relationship between awareness and subsequent vaccination was either not statistically significant or not meaningful in magnitude, with R(2) = 0.004 to 0.02. The predicted probability of getting vaccination was <0.50 for all awareness levels and prediction accuracy was poor (area under the curve = 0.56-0.64).

CONCLUSIONS

In this high-risk population, levels of awareness among parents and adolescents were not substantially related to subsequent adolescent HPV vaccination.

Collaborative patient-provider communication and uptake of adolescent vaccines

RATIONALE

Recommendations from healthcare providers are one of the most consistent correlates of adolescent vaccination, but few studies have investigated other elements of patient-provider communication and their relevance to uptake.

OBJECTIVE

We examined competing hypotheses about the relationship of patient-driven versus provider-driven communication styles with vaccination.

METHODS

We gathered information about vaccine uptake from healthcare provider-verified data in the 2010 National Immunization Survey-Teen for tetanus, diphtheria, and pertussis (Tdap) booster, meningococcal vaccine, and human papillomavirus (HPV) vaccine (initiation among females) for adolescents ages 13-17. We categorized communication style in parents' conversations with healthcare providers about vaccines, based on parents' reports (of whether a provider recommended a vaccine and, if so, if conversations were informed, shared, or efficient) (N = 9021).

RESULTS

Most parents reported either no provider recommendation (Tdap booster: 35%; meningococcal vaccine: 46%; and HPV vaccine: 31%) or reported a provider recommendation and shared patient-provider communication (43%, 38%, and 49%, respectively). Provider recommendations were associated with increased odds of vaccination (all ps < 0.001). In addition, more provider-driven communication styles were associated with higher rates of uptake for meningococcal vaccine (efficient style: 82% vs. shared style: 77% vs. informed style: 68%; p < 0.001 for shared vs. informed) and HPV vaccine (efficient style: 90% vs. shared style: 70% vs. informed style: 33%; p < 0.05 for all comparisons).

CONCLUSION

Efficient communication styles were used rarely (≤2% across vaccines) but were highly effective for encouraging meningococcal and HPV vaccination. Intervention studies are needed to confirm that efficient communication approaches increase HPV vaccination among adolescents.

Influence of sources of information about influenza vaccine on parental attitudes and adolescent vaccine receipt

In 2011-2012, only 34% of 13-17 years olds in the United States (US) received seasonal influenza vaccine. Little is known about the link between parents' sources of health information, their vaccine-related attitudes, and vaccination of their adolescent against influenza. This study seeks to determine the relationship between number of sources of information on influenza vaccine, parental attitudes toward influenza vaccine, and influenza vaccine uptake in adolescents. We conducted a telephone and web-based survey among US parents of students enrolled in 6 middle and 5 high schools in Georgia. Bivariate and multivariable analyses were conducted to examine associations between the number of information sources about influenza vaccine and vaccine receipt and whether parent vaccine-related attitudes act as a mediator. The most commonly reported sources of information were: a physician/medical professional (95.0%), a family member or friend (80.6%), and television (77.2%). Parents who had higher attitude scores toward influenza vaccine were 5 times as likely to report their adolescent had ever received influenza vaccine compared to parents who had lower attitude scores (adjusted odds ratio (aOR) 5.1; 95% confidence intervals (CI) 3.1-8.4; P < 0.01). Parent vaccine-related attitudes were a significant mediator of the relationship between sources of information and vaccine receipt. In light of the low response rate and participation in an adolescent vaccination intervention, findings may not be generalizable to other populations. This study shows the importance of multiple sources of information in influencing parental decision-making about influenza vaccine for adolescents. Harnessing the power of mass media and family members and friends as health advocates for influenza vaccination can potentially help increase vaccination coverage of adolescents.

Parents' perceptions of provider communication regarding adolescent vaccines

Strong provider recommendations for adolescent vaccines are critical for achieving high vaccination levels.  However, little is known about parents' preferred provider communication strategies for adolescent vaccines in general, and for human papillomavirus (HPV) vaccines specifically. We performed a cross-sectional survey of 800 parents of 9-14 year olds in April 2014 to assess current adolescent vaccine communication practices by providers, parents' preferred HPV vaccine-specific communication strategies, and the association of these two outcomes with experiential, attitudinal and demographic characteristics.  Among the 356 parents in the study (response rate 48%), HPV vaccines were reported as less likely to have been "very strongly" recommended by their adolescent's provider (39%) than other adolescent-targeted vaccines (45%-59%, <0.05 for all comparisons).  Receiving a very strong recommendation for HPV vaccines was associated with a higher likelihood of vaccine receipt (71% versus 39%, p<0.001), or among those not yet vaccinated, increased likelihood of positive vaccination intentions (82% vs. 60%, p = 0.015).  Nearly all parents (87%) reported that, if available, they would use a website providing personalized HPV vaccine-related materials before their adolescent's next check-up, and other technology-based communications were also endorsed by the majority of parents.   From these data we conclude that parents received weaker recommendations for HPV vaccines than other adolescent vaccines, and that most parents want additional HPV vaccine-related materials, preferably delivered using a variety of technology-based modalities which is not their providers' current practice.

Summer Peaks in Uptake of Human Papillomavirus and Other Adolescent Vaccines in the United States

BACKGROUND

Seasonality in human papillomavirus (HPV) vaccination could have a large impact on national cancer prevention efforts. We hypothesized that uptake of HPV vaccine and other adolescent vaccines in the United States would be highest in the summer.

METHODS

Data came from health care provider-verified vaccination records for 70,144 adolescents (ages 13-17 years) from the 2008 to 2012 versions of the National Immunization Survey-Teen. Using the Edwards method for testing annual trends, we examined seasonal patterns in the uptake of HPV and other recommended adolescent vaccines [tetanus, diphtheria, and pertussis (Tdap) booster and meningococcal vaccine]. HPV vaccine initiation (receipt of the first of the three-dose series) data were for female adolescents.

RESULTS

Uptake for HPV and other adolescent vaccines peaked in the summer across years and states (all P < 0.001). Uptake was five times as frequent at the peak as at the trough for HPV vaccine, and HPV vaccine initiation was highest in June, July, and August (percent of doses delivered in these months: 38.7%). The same pattern existed for Tdap booster and meningococcal vaccine. Concomitant (same-day) vaccination of HPV vaccine with other adolescent vaccines also demonstrated summer peaks each year nationally (all P < 0.001).

CONCLUSION

Uptake of adolescent vaccines increased dramatically in summer months. These summer peaks are an important opportunity for interventions focused on concomitant vaccination.

IMPACT

The potential cancer prevention impact of HPV vaccination programs could be increased, for example, by delivering messages about concomitant vaccination during the summer, when adolescents and their parents might be most open to them.

Interventions to Improve Adolescent Vaccination: What May Work and What Still Needs to Be Tested

Since the development of the "adolescent platform" of vaccination in 1997, hundreds of studies have been conducted, identifying barriers to and facilitators of adolescent vaccination. More recent research has focused on developing and evaluating interventions to increase uptake of adolescent vaccines. This review describes a selection of recent intervention studies for increasing adolescent vaccination, divided into three categories: those with promising results that may warrant more widespread implementation, those with mixed results requiring more research, and those with proven effectiveness in other domains that have not yet been tested with regard to adolescent vaccination.

Knowledge of HPV and HPV Vaccine among Women Ages 19 to 26

OBJECTIVE

To describe knowledge about human papillomavirus (HPV) and HPV vaccination among women ages 19 to 26 seeking a variety of services at reproductive health centers. A secondary objective was to identify common sources of HPV information.

METHODS

Ten reproductive health centers enrolled 365 women ages 19 to 26 in a randomized, controlled trial to determine the effect of automated reminder messages on HPV vaccine completion. Using responses from a 61-item self-administered baseline questionnaire completed before initiating the HPV vaccine, this subanalysis assessed participants' knowledge regarding HPV and the HPV vaccine.

RESULTS

Knowledge of HPV prevention, transmission, and disease outcomes among the study population was highly variable. The mean HPV knowledge score was 11.0 of a possible 19 (SD = 3.8). Most participants (77%) had heard of the HPV vaccine before completing the questionnaire and indicated that their primary sources of information about the vaccine were television ads (61%), health care providers (52%), and friends (45%).

CONCLUSIONS

Despite a relatively high awareness of the vaccine, specific knowledge regarding HPV and the HPV vaccine varied substantially and participant scores highlighted knowledge gaps among vaccine-eligible young women. Media, health care providers, and friends were identified by participants as sources of information and may influence their knowledge of HPV and the HPV vaccine.

Effect of decision support on missed opportunities for human papillomavirus vaccination

BACKGROUND

Missed opportunities for human papilloma virus (HPV) vaccination are common, presenting a barrier to achieving widespread vaccine coverage and preventing infection.

PURPOSE

To compare the impact of clinician- versus family-focused decision support, none, or both on captured opportunities for HPV vaccination.

DESIGN

Twelve-month cluster randomized controlled trial conducted in 2010-2011.

SETTING/PARTICIPANTS

Adolescent girls aged 11-17 years due for HPV Dose 1, 2, or 3 receiving care at primary care practices.

INTERVENTION

Twenty-two primary care practices were cluster randomized to receive a three-part clinician-focused intervention (educational sessions, electronic health record-based alerts, and performance feedback) or none. Within each practice, girls were randomized at the patient level to receive family-focused, automated, educational phone calls or none. Randomization resulted in four groups: clinician-focused, family-focused, combined, or no intervention.

MAIN OUTCOME MEASURES

Standardized proportions of captured opportunities (due vaccine received at clinician visit) were calculated among girls in each study arm. Analyses were conducted in 2013.

RESULTS

Among 17,016 adolescent girls and their 32,472 visits (14,247 preventive, 18,225 acute), more HPV opportunities were captured at preventive than acute visits (36% vs 4%, p<0.001). At preventive visits, the clinician intervention increased captured opportunities by 9 percentage points for HPV-1 and 6 percentage points for HPV-3 (p≤0.01), but not HPV-2. At acute visits, the clinician and combined interventions significantly improved captured opportunities for all three doses (p≤0.01). The family intervention was similar to none. Results differed by practice setting; at preventive visits, the clinician intervention was more effective for HPV-1 in suburban than urban settings, whereas at acute visits, the clinician intervention was more effective for all doses at urban practices.

CONCLUSIONS

Clinician-focused decision support is a more effective strategy than family-focused to prevent missed HPV vaccination opportunities. Given the persistence of missed opportunities even in intervention groups, complementary strategies are needed. This study is registered at clinicaltrials.gov NCT01159093.

The Vaccination Confidence Scale: a brief measure of parents' vaccination beliefs

PURPOSE

The success of national immunization programs depends on the public's confidence in vaccines. We sought to develop a scale for measuring confidence about adolescent vaccination in diverse populations of parents.

METHODS

Data came from 9623 parents who completed the 2010 National Immunization Survey-Teen, an annual, population-based telephone survey. Parents reported on a 13- to 17-year-old child in their households. We used exploratory and confirmatory factor analysis to identify latent constructs underlying parents' responses to 8 vaccination belief survey items (response scale 0-10) conceptualized using the Health Belief Model. We assessed the scale's psychometric properties overall and across demographic subgroups.

RESULTS

Parents' confidence about adolescent vaccination was generally high. Analyses provided support for three factors assessing benefits of vaccination (mean=8.5), harms of vaccination (mean=3.3), and trust in healthcare providers (mean=9.0). The model showed good fit both overall (comparative fit index=0.97) and across demographic subgroups, although internal consistency was variable for the three factors. We found lower confidence among several potentially vulnerable subpopulations, including mothers with lower levels of education and parents whose children were of Hispanic ethnicity (both p<0.05).

CONCLUSIONS

Our brief, three-factor scale offers an efficient way to measure confidence in adolescent vaccination across demographic subgroups. Given evidence of lower confidence by educational attainment and race/ethnicity, program planners should consider factors such as health literacy and cultural competence when designing interventions to promote adolescent vaccination to ensure these programs are fully accessible.