The Role of Cognitive Bias in Suboptimal HPV Vaccine Uptake

Understanding the Factors Influencing Health Care Provider Recommendations about Adolescent Vaccines: A Proposed Framework

Health care provider recommendations are among the most important factors influencing parents' decisions to vaccinate their adolescents. However, delivery of high-quality health care provider recommendations for vaccination is not universal. There is wide variation in the strength, timeliness and consistency of the delivery of recommendations for all adolescent vaccines. The factors that influence health care providers' recommendations are multi-level and can be conceptualized in much the same way as vaccine acceptance among parents. Health care providers are influenced by their own attitudes and beliefs about a vaccine and also by the patient they are treating and by the community in which they practice as well as state and national level vaccine policy. We propose a multi-level framework for understanding the factors that influence health care providers' recommendations at the individual, interpersonal and community level to both develop and adapt interventions to improve providers' recommendations.

Facts Tell, Stories Sell? Assessing the Availability Heuristic and Resistance as Cognitive Mechanisms Underlying the Persuasive Effects of Vaccination Narratives

Online vaccine-critical sentiments are often expressed in appealing personal narratives, whereas vaccine-supporting information is often presented in a non-narrative, expository mode describing scientific facts. In two experiments, we empirically test whether and how these different formats impact the way in which readers process and retrieve information about childhood vaccination, and how this may impact their perceptions regarding vaccination. We assess two psychological mechanisms that are hypothesized to underlie the persuasive nature of vaccination narratives: the availability heuristic (experiment 1, N = 418) and cognitive resistance (experiment 2, N = 403). The results of experiment 1 showed no empirical evidence for the availability heuristic, but exploratory analyses did indicate that an anti-vaccination narrative (vs. expository) might reduce cognitive resistance, decrease vaccination attitudes and reduce attitude certainty in a generally pro-vaccination sample, especially for those who were more vaccine hesitant. Preregistered experiment 2 formally tested this and showed that not narrative format, but prior vaccine hesitancy predicts cognitive resistance and post-reading attitudes. Hesitant participants showed less resistance toward an anti-vaccine text than vaccine-supporting participants, as well as less positive post-reading attitudes and attitude certainty. These findings demonstrate belief consistency effects rather than narrative persuasion, which has implications for scientific research as well as public health policy.

Vaccine hesitancy: evidence from an adverse events following immunization database, and the role of cognitive biases

BACKGROUND

Vaccine hesitancy has been a growing challenge for public health in recent decades. Among factors contributing to vaccine hesitancy, concerns regarding vaccine safety and Adverse Events (AEs) play the leading role. Moreover, cognitive biases are critical in connecting such concerns to vaccine hesitancy behaviors, but their role has not been comprehensively studied. In this study, our first objective is to address concerns regarding vaccine AEs to increase vaccine acceptance. Our second objective is to identify the potential cognitive biases connecting vaccine hesitancy concerns to vaccine-hesitant behaviors and identify the mechanism they get triggered in the vaccine decision-making process.

METHODS

First, to mitigate concerns regarding AEs, we quantitatively analyzed the U.S. Vaccine Adverse Event Reporting System (VAERS) from 2011 to 2018 and provided evidence regarding the non-severity of the AEs that can be used as a communicable summary to increase vaccine acceptance. Second, we focused on the vaccination decision-making process. We reviewed cognitive biases and vaccine hesitancy literature to identify the most potential cognitive biases that affect vaccine hesitancy and categorized them adopting the Precaution Adoption Process Model (PAPM).

RESULTS

Our results show that the top frequent AEs are expected mild reactions like injection site erythema (4.29%), pyrexia (3.66%), and injection site swelling (3.21%). 94.5% of the reports are not serious and the average population-based serious reporting rate over the 8 years was 25.3 reports per 1 million population. We also identified 15 potential cognitive biases that might affect people's vaccination decision-making and nudge them toward vaccine hesitancy. We categorized these biases based on the factors that trigger them and discussed how they contribute to vaccine hesitancy.

CONCLUSIONS

This paper provided an evidence-based communicable summary of VAERS. As the most trusted sources of vaccine information, health practitioners can use this summary to provide evidence-based vaccine information to vaccine decision-makers (patients/parents) and mitigate concerns over vaccine safety and AEs. In addition, we identified 15 potential cognitive biases that might affect the vaccination decision-making process and nudge people toward vaccine hesitancy. Any plan, intervention, and message to increase vaccination uptake should be modified to decrease the effect of these potential cognitive biases.

Recent advances in addressing vaccine hesitancy

PURPOSE OF REVIEW

To offer healthcare providers current, evidence-based approaches for addressing vaccine hesitancy to increase vaccine coverage and reduce the frequency of vaccine-preventable disease outbreaks.

RECENT FINDINGS

Vaccine hesitancy is a growing problem with profound societal, economic, and medical consequences. Understanding the complexity of vaccine hesitancy can inform approaches to increasing vaccine uptake on both the individual and population levels. Notably, pediatricians play a critical role in increasing vaccine uptake due to their relationships with families. This doctor-patient relationship establishes trust and allows evidence-based intervention strategies to be effective in the office. Understanding potential solutions outside the office, such as media campaigns and policy changes, also provide insight into vaccine hesitancy and potential directions for future research. While pediatricians' attempts in the clinic to increase coverage remain crucial, vaccine hesitancy remains a formidable public health problem that requires attention on both the micro and macro levels to be addressed successfully.

SUMMARY

Providers have an opportunity to increase both confidence in and uptake of vaccines. Public health interventions would effectively complement strategies in the clinic to increase overall coverage.

Association of cognitive biases with human papillomavirus vaccine hesitancy: a cross-sectional study

Given the link between vaccine hesitancy and vaccine-preventable disease outbreaks, it is critical to examine the cognitive processes that contribute to the development of vaccine hesitancy, especially among parents of adolescents. We conducted a secondary analysis of baseline data from a two-phase randomized trial on human papillomavirus to investigate how vaccine hesitancy and intent to vaccinate are associated with six decision-making factors: base rate neglect, conjunction fallacy, sunk cost bias, present bias, risk aversion, and information avoidance. We recruited 1,413 adults residing in the United States with at least one daughter aged 9-17 years old through an online survey on Amazon Mechanical Turk. Vaccine hesitancy, intent to vaccinate, and susceptibility to cognitive biases was measured through a series of brief questionnaires. 1,400 participants were in the final analyzed sample. Most participants were white (74.1%), female (71.6%), married (75.3%), and had a college or graduate/professional education (88.8%). Conjunction fallacy, sunk cost bias, information avoidance, and present bias may be associated with vaccine hesitancy. Intent to vaccinate may be associated with information avoidance. These results suggest that cognitive biases play a role in developing parental vaccine hesitancy and vaccine-related behavior.

Cognitive Bias in Clinicians' Communication about Human Papillomavirus Vaccination

National guidelines recommend human papillomavirus (HPV) vaccination for all 11-12-year-olds, but uptake among United States adolescents remains low. A major barrier to greater uptake is the lack of effective recommendations for HPV vaccine from clinicians. One potential influence on clinicians' recommendations for HPV vaccine that has been relatively unexplored is that of cognitive biases, or errors in judgement that result from 'mental shortcuts' used to make decisions under uncertainty. Therefore, we analyzed qualitative data from interviews with 32 pediatric clinicians using a framework of nine cognitive biases relevant to HPV vaccination: omission bias, ambiguity aversion, present bias, availability bias, optimism bias, naturalness bias, protected values, anchoring bias, and confirmation bias. We used a directed content analysis approach to iteratively code and analyze all transcripts in the dataset. We found evidence for several cognitive biases that were related to weaker recommendations for HPV vaccine. Commonly identified biases included anchoring bias (perception that vaccination unnecessary due to age/pubertal status); present bias (perception of burdens related to discussing vaccination), and optimism bias (belief that patient at low risk for HPV acquisition). We found less frequent evidence for ambiguity aversion (perception of missing information regarding vaccination) and omission bias (deferring vaccination). Other biases were identified infrequently or not at all. Our findings suggest that several cognitive biases may be an influence on clinicians' communication about HPV vaccine. Raising awareness of cognitive biases related to making HPV vaccine recommendations could help to strengthen the recommendations that clinicians provide.

HPV vaccine recommendation profiles among a national network of pediatric practitioners: understanding contributors to parental vaccine hesitancy and acceptance

Background: Practitioner communication is one of the most important influences and predictors of HPV vaccination uptake. The objective of this study was to conduct a latent class analysis characterizing pediatric practitioner HPV recommendation patterns. Methods: Pediatric practitioners of the American Academy of Pediatrics' (AAP) Pediatric Research in Office Settings (PROS) national network completed an online survey where they were presented with 5 hypothetical vignettes of well child visits and responded to questions. Questions asked about their use of communication strategies, assessments about the adolescent patient becoming sexually active in the next 2 years for decision-making about HPV vaccine recommendation, and peer norms. Latent class analysis characterized practitioner subgroups based on their response patterns to 10 survey questions. Multinomial logistic regression examined practitioner characteristics associated with each profile. Results: Among 470 respondents, we identified three distinct practitioner HPV vaccine recommendation profiles: (1) Engagers (52%) followed national age-based guidelines, strongly recommended HPV vaccination, and perceived peers as strongly recommending; (2) Protocol Followers (20%) also strongly recommended HPV vaccination, but were less likely to engage families in a discussion about benefits; and (3) Ambivalent HPV Vaccine Recommenders (28%) delayed or did not recommend HPV vaccination and were more likely to use judgment about whether adolescents will become sexually active in the next two years. Practicing in a suburban setting was associated with twice the odds of being an Ambivalent Recommender relative to being an Engager (OR = 2.2; 95% CI:1.1-4.1). Conclusions: Findings underscore the importance of continued efforts to bolster practitioner adoption of evidence-based approaches to HPV vaccine recommendation especially among Ambivalent Recommenders.

Influence of health literacy on acceptance of influenza and pertussis vaccinations: a cross-sectional study among Spanish pregnant women

OBJECTIVES

Immunisations against influenza and Bordetella pertussis infection are recommended to pregnant women in Valencia (Spain), yet vaccination rates remain low. Health literacy (HL) appears as a crucial factor in vaccination decision-making. We explored the relation between HL of pregnant women and decisions to receive influenza and pertussis immunisations.

SETTING

University hospital in Valencia (Spain).

PARTICIPANTS

119 women who gave birth at a hospital in Valencia (Spain) between November 2015 and May 2016. Women in the immediate postpartum period (more than 27 weeks of gestation), between November 2015 and May 2016 were included in the study. Women with impairments, language barriers or illiteracy which prevented completion of the questionnaires, or those who were under 18 years were excluded from enrolment.

PRIMARY AND SECONDARY OUTCOME MEASURES

HL level; influenza and pertussis immunisation rate; reasons for rejection of vaccination.

RESULTS

119 participants were included (mean age 32.3±5.5 years, 52% primiparous, 95% full-term deliveries). A higher education level was associated with Short Assessment of Health Literacy for Spanish Adults _50 (adjusted R²=0.22, p=0.014) and Newest Vital Sign (adjusted R²=0.258, p=0.001) scores. Depending on the scale, 56%-85% of participants had adequate HL. 52% (62/119) and 94% (112/119) of women received influenza and pertussis immunisation, respectively. Women rejecting influenza vaccine had a higher HL level (measured by SALHSA_50 tool) than those accepting it (Kruskal-Wallis test p=0.022). 24% of women who declined influenza vaccination felt the vaccine was unnecessary, and 23% claimed to have insufficient information.

CONCLUSIONS

Influenza vaccination rate was suboptimal in our study. Women with high HL were more likely to decline immunisation. Information from professionals needs to match patients' HL levels to reduce negative perceptions of vaccination.

Lack of school requirements and clinician recommendations for human papillomavirus vaccination

BACKGROUND

A strong recommendation from a clinician is one of the best predictors of human papillomavirus (HPV) vaccination among adolescents, yet many clinicians do not provide effective recommendations. The objective of this study was to understand how the lack of school entry requirements for HPV vaccination influences clinicians' recommendations.

DESIGN AND METHODS

Semi-structured interviews with a purposive sample of 32 clinicians were conducted in 2015 in Connecticut USA. Data were analysed using an iterative thematic approach in 2016-2017.

RESULTS

Many clinicians described presenting HPV vaccination as optional or non-urgent because it is not required for school entry. This was noted to be different from how other required vaccines were discussed. Even strong recommendations were often qualified by statements about the lack of requirements. Furthermore, lack of requirements was often raised initially by clinicians and not by parents. Many clinicians agreed that requirements would simplify the recommendation, but that parents may not agree with requirements. Personal opinions about school entry requirements were mixed.

CONCLUSIONS

The current lack of school entry requirements for HPV vaccination is an important influence on clinicians' recommendations that are often framed as optional or non-urgent. Efforts are needed to strengthen the quality of clinicians' recommendations in a way that remains strong and focused on disease prevention yet uncoupled from the lack of requirements that may encourage delays. Additionally, greater support for requirements among clinicians may be needed to successfully enact requirements in the future.

Missed Opportunities for Human Papillomavirus Vaccine Initiation in an Insured Adolescent Female Population

BACKGROUND

This study assessed the initiation of HPV vaccination in insured adolescent females in relation to physician visits and receipt of other vaccines routinely given at the same age.

METHODS

January 1, 2010, and September 31, 2015. Vaccination administration was determined by using Current Procedural Terminology codes. A missed opportunity was defined as the absence of an HPV vaccine at the following encounter types: visits with a 4-valent meningococcal conjugate vaccine (MenACWY) or tetanus, diphtheria, and acellular pertussis (Tdap) vaccine claim; well adolescent visits; or any encounter with a primary care provider (PCP). Missed opportunities were stratified by type of provider (pediatrician or nonpediatrician).

RESULTS

Among 14588 adolescent girls, only 6098 (41.8%) initiated the HPV vaccine series. HPV vaccine was given at 37.1% of visits when a Tdap or MenACWY vaccine was administered, 26.0% of well adolescent visits and 41.8% of PCP visits. Pediatricians had fewer missed opportunities than nonpediatricians to administer HPV (50.7% vs 60.8%), as well as Tdap, although the difference was larger for Tdap (7.0% vs 29.6%).

CONCLUSIONS

These data indicate that pediatricians and nonpediatricians alike are missing opportunities to administer the HPV vaccine when other adolescent vaccines are given. Efforts should be focused on converting these missed vaccination opportunities into cancer-prevention visits.