Publications

Below is a list of some of our recent publications!

Zhu, P., Tatar, O., Haward, B., Steck, V., Griffin-Mathieu, G., Perez, S., Dubé, È., Zimet, G., Rosberger, Z. (2023) Examining an Altruism-Eliciting Video Intervention to Increase COVID-19 Vaccine Intentions in Younger Adults: A Qualitative Assessment Using the Realistic Evaluation Framework. Vaccines, 11(3), 628. https://doi.org/10.3390/vaccines11030628

COVID-19 vaccine-induced immunity wanes over time, and with the emergence of new variants, additional “booster” doses have been recommended in Canada. However, booster vaccination uptake has remained low, particularly amongst younger adults aged 18–39. A previous study by our research team found that an altruism-eliciting video increased COVID-19 vaccination intentions. Using qualitative methods, the present study aims to: (1) identify the factors that influence vaccine decision-making in Canadian younger adults; (2) understand younger adults’ perceptions of an altruism-eliciting video designed to increase COVID-19 vaccine intentions; and (3) explore how the video can be improved and adapted to the current pandemic context. We conducted three focus groups online with participants who: (1) received at least one booster vaccine, (2) received the primary series without any boosters, or (3) were unvaccinated. We used deductive and inductive approaches to analyze data. Deductively, informed by the realist evaluation framework, we synthesized data around three main themes: context, mechanism, and intervention-specific suggestions. Within each main theme, we deductively created subthemes based on the health belief model (HBM). For quotes that could not be captured by these subthemes, additional themes were created inductively. We found multiple factors that could be important considerations in future messaging to increase vaccine acceptance, such as feeling empowered, fostering confidence in government and institutions, providing diverse (such as both altruism and individualism) messaging, and including concrete data (such as the prevalence of vulnerable individuals). These findings suggest targeted messaging tailored to these themes would be helpful to increase COVID-19 booster vaccination amongst younger adults.

Tatar, O., Haward, B., Zhu, P., Griffin-Mathieu, G., Perez, S., McBride, E., Lofters, A. K., Smith, L. W., Maryland, M. H., Daley, E. M., Brotherton, J. M. L., Zimet, G. D., & Rosberger, Z. (2023). Understanding the Challenges of HPV-Based Cervical Screening: Development and Validation of HPV Testing and Self-Sampling Attitudes and Beliefs Scales. Current Oncology30(1), 1206-1219.

The disrupted introduction of the HPV-based cervical screening program in several jurisdictions has demonstrated that the attitudes and beliefs of screening-eligible persons are critically implicated in the success of program implementation (including the use of self-sampling). As no up-to-date and validated measures exist measuring attitudes and beliefs towards HPV testing and self-sampling, this study aimed to develop and validate two scales measuring these factors. In October-November 2021, cervical screening-eligible Canadians participated in a web-based survey. In total, 44 items related to HPV testing and 13 items related to HPV self-sampling attitudes and beliefs were included in the survey. For both scales, the optimal number of factors was identified using Exploratory Factor Analysis (EFA) and parallel analysis. Item Response Theory (IRT) was applied within each factor to select items. Confirmatory Factor Analysis (CFA) was used to assess model fit. After data cleaning, 1027 responses were analyzed. The HPV Testing Attitudes and Beliefs Scale (HTABS) had four factors, and twenty-two items were retained after item reduction. The HPV Self-sampling Attitudes and Beliefs Scale (HSABS) had two factors and seven items were retained. CFA showed a good model fit for both final scales. The developed scales will be a valuable resource to examine attitudes and beliefs in anticipation of, and to evaluate, HPV test-based cervical screening.

Haward, B., Tatar, O., Zhu, P., Griffin-Mathieu, G., Perez, S., Shapiro, G. K., McBride, E., Zimet, G. D., & Rosberger, Z. (2022). Development and validation of the cervical cancer knowledge scale and HPV testing knowledge scale in a sample of Canadian women. Preventive Medicine Reports, 30, 102017. https://doi.org/https://doi.org/10.1016/j.pmedr.2022.102017 

Knowledge of cervical cancer and HPV testing are important factors in proactive and continued engagement with screening and are critical considerations as countries move towards the implementation of HPV-based primary screening programs. However, existing scales measuring knowledge of both cervical cancer and HPV testing are not up to date with the current literature, lack advanced psychometric testing, or have suboptimal psychometric properties. Updated, validated scales are needed to ensure accurate measurement of these factors. Therefore, the aim of this study was to develop and validate two scales measuring cervical cancer knowledge and HPV testing knowledge. A pool of items was generated by retaining relevant existing items identified in a 2019 literature search and developing new items according to themes identified in recent systematic reviews. Items were assessed for relevance by the research team and then refined through seven cognitive interviews with Canadian women. A web-based survey including the remaining items (fourteen for each scale development) was administered to a sample of Canadian women in October and November of 2021. After data cleaning, N = 1027 responses were retained. Exploratory and Confirmatory Factor Analysis were conducted, and Item Response Theory was used to select items. The final cervical cancer knowledge scale (CCKS) and HPV testing knowledge scale (HTKS) were unidimensional, and each consisted of eight items. CFA demonstrated adequate model fit for both scales. The developed scales will be important tools to identify knowledge gaps and inform communications about cervical cancer screening, particularly in the context of HPV-based screening implementation.

Zhu, P., Tatar, O., Haward, B., Griffin-Mathieu, G., Perez, S., Smith, L., Brotherton, J., Ogilvie, G., & Rosberger, Z. (2022). Assessing Canadian women’s preferences for cervical cancer screening: A brief report [Brief Research Report]. Frontiers in Public Health, 10. https://doi.org/10.3389/fpubh.2022.962039 

Human papillomavirus (HPV) testing is recommended for primary screening for cervical cancer by several health authorities. Several countries that have implemented HPV testing programs have encountered resistance against extended screening intervals and older age of initiation. As Canada prepares to implement HPV testing programs, it is important to understand women’s preferences toward cervical cancer screening to ensure a smooth transition. The objective of this study was to assess Canadian women’s current preferences toward cervical cancer screening. Using a web-based survey, we recruited underscreened ( > 3 years since last Pap test) and adequately screened (< 3 years since last Pap test) Canadian women aged 21–70 who were biologically female and had a cervix. We used Best-Worst Scaling (BWS) methodology to collect data on women’s preferences for different screening methods, screening intervals, and ages of initiation. We used conditional logistic regression to estimate preferences in both subgroups. In both subgroups, women preferred screening every three years compared to every five or ten years, and initiating screening at age 21 compared to age 25 or 30. Adequately screened women (n = 503) most preferred co-testing, while underscreened women (n = 524) preferred both co-testing and HPV self-sampling over Pap testing. Regardless of screening status, women preferred shorter screening intervals, an earlier age of initiation, and co-testing. Adequate communication from public health authorities is needed to explain the extended screening intervals and age of initiation to prevent resistance against these changes to cervical cancer screening.

Griffin-Mathieu, G., Haward, B., Tatar, O., Zhu, P., Perez, S., Shapiro, G. K., McBride, E., Thompson, E. L., Smith, L. W., Lofters, A. K., Daley, E. M., Guichon, J. R., Waller, J., Steben, M., Decker, K. M., Mayrand, M.-H., Brotherton, J. M. L., Ogilvie, G. S., Zimet, G. D., . . . Rosberger, Z. (2022). Ensuring a successful transition from Cytology to HPV-based primary cervical cancer screening in Canada by investigating the psychosocial correlates of women’s intentions: Protocol for an observational study. JMIR Research Protocols, 11(6), e38917. https://doi.org/10.2196/38917 

Background: The human papillomavirus (HPV) test has emerged as a significant improvement over cytology for primary cervical cancer screening. In Canada, provinces and territories are moving toward implementing HPV testing in cervical cancer screening programs. Although an abundance of research exists on the benefits of HPV-based screening, there is a dearth of research examining women’s understanding of HPV testing. In other countries, failure to adequately address women’s concerns about changes has disrupted the implementation of HPV-based screening.

Objective: The aims of the multipart study described in this paper are to develop psychometrically valid measures of cervical cancer screening–related knowledge, attitudes, and beliefs; to examine the feasibility of a questionnaire examining psychosocial factors related to HPV-based screening; and to investigate psychosocial correlates of women’s intentions to participate in HPV-based screening.

Methods: We conducted a web-based survey (study 1) of Canadian women to assess the acceptability and feasibility of a questionnaire, including the validation of scales examining cervical cancer knowledge, HPV testing knowledge, HPV testing attitudes and beliefs, and HPV test self-sampling attitudes and beliefs. Preferences for cervical cancer screening were assessed using the best-worst scaling methodology. A second web-based survey (study 2) will be administered to a national sample of Canadian women between June 2022 and July 2022 using the validated scales. Differences in the knowledge, attitudes, beliefs, and preferences of women who are currently either underscreened or adequately screened for cervical cancer will be examined through bivariate analyses. Multinomial logistic regression will be used to estimate the associations between psychosocial and sociodemographic factors and intentions to undergo HPV-based screening.

Results: Between October 2021 and November 2021, a total of 1230 participants completed the questionnaire in study 1, and 1027 (83.49%) responses were retained after data cleaning methods were applied. Feasibility was comparable with similar population-based surveys in terms of survey length, participant attrition, and the number of participants excluded after data cleaning. As of May 2022, analysis of study 1 is ongoing, and results are expected to be published in the summer of 2022. Data collection is expected to begin for study 2 in the summer of 2022. Results are expected to be published between late 2022 and early 2023.

Conclusions: Findings will provide direction for Canadian public health authorities to align guidelines to address women’s concerns and optimize the acceptability and uptake of HPV-based primary screening. Validated scales can be used by other researchers to improve and standardize the measurement of psychosocial factors affecting HPV test acceptability. Study results will be disseminated through peer-reviewed journal articles; conference presentations; and direct communication with researchers, clinicians, policy makers, media, and specialty organizations.

International Registered Report Identifier (IRRID): DERR1-10.2196/38917

Zhu, P., Tatar, O., Griffin-Mathieu, G., Perez, S., Haward, B., Zimet, G., Tunis, M., Dubé, E., Rosberger, Z. (2022). The Efficacy of a Brief, Altruism-Eliciting Video Intervention in Enhancing COVID-19 Vaccination Intentions Among a Population-Based Sample of Younger Adults: Randomized Controlled Trial. JMIR Public Health and Surveillance, 8(5), e37238. https://doi.org/10.2196/37328

Background: High COVID-19 vaccine uptake is crucial to containing the pandemic and reducing hospitalizations and deaths. Younger adults (aged 20-39 years) have demonstrated lower levels of vaccine uptake compared to older adults, while being more likely to transmit the virus due to a higher number of social contacts. Consequently, this age group has been identified by public health authorities as a key target for vaccine uptake. Previous research has demonstrated that altruistic messaging and motivation is associated with vaccine acceptance.

Objective: This study had 2 objectives: (1) to evaluate the within-group efficacy of an altruism-eliciting short, animated video intervention in increasing COVID-19 vaccination intentions amongst unvaccinated Canadian younger adults and (2) to examine the video’s efficacy compared to a text-based intervention focused exclusively on non-vaccine-related COVID-19 preventive health measures.

Methods: Using a web-based survey in a pre-post randomized control trial (RCT) design, we recruited Canadians aged 20-39 years who were not yet vaccinated against COVID-19 and randomized them in a 1:1 ratio to receive either the video intervention or an active text control. The video intervention was developed by our team in collaboration with a digital media company. The measurement of COVID-19 vaccination intentions before and after completing their assigned intervention was informed by the multistage Precaution Adoption Process Model (PAPM). The McNemar chi-square test was performed to evaluate within-group changes of vaccine intentions. Exact tests of symmetry using pairwise McNemar tests were applied to evaluate changes in multistaged intentions. Between-group vaccine intentions were assessed using the Pearson chi-square test postintervention.

Results: Analyses were performed on 1373 participants (n=686, 50%, in the video arm, n=687, 50%, in the text arm). Within-group results for the video intervention arm showed that there was a significant change in the intention to receive the vaccine (χ21=20.55, P<.001). The between-group difference in postintervention intentions (χ23=1.70, P=.64) was not significant. When administered the video intervention, we found that participants who had not thought about or were undecided about receiving a COVID-19 vaccine were more amenable to change than participants who had already decided not to vaccinate.

Conclusions: Although the video intervention was limited in its effect on those who had firmly decided not to vaccinate, our study demonstrates that prosocial and altruistic messages could increase COVID-19 vaccine uptake, especially when targeted to younger adults who are undecided or unengaged regarding vaccination. This might indicate that altruistic messaging provides a “push” for those who are tentative toward, or removed from, the decision to receive the vaccine. The results of our study could also be applied to more current COVID-19 vaccination recommendations (eg, booster shots) and for other vaccine-preventable diseases.

Tatar, O., Haward, B., Zhu, P., Griffin-Mathieu, G., Perez, S., Zimet, G., & Rosberger, Z. (2022). Using Best-Worst Scaling to investigate younger adult Canadians’ preferences for COVID-19 vaccination and public health measures: an observational study. Preventive Medicine Reports, 101755. https://doi.org/10.1016/j.pmedr.2022.101755

Containing the COVID-19 pandemic is dependent on compliance with public health recommendations and mandates which is lower in younger compared to older adults. Furthermore, younger adults have demonstrated lower uptake of COVID-19 vaccines. The aim of this study was to assess preferences for COVID-19 related preventive health measures and vaccination and to explore their association with COVID-19 vaccine acceptability. Canadians aged 18–39 years were invited to participate in a web-based survey in August 2021. We used the Best-Worst-Scaling (BWS) methodology to collect and analyze preference data and multivariable binary logistic regression to estimate associations with vaccine acceptability. Based on 266 complete responses, we found strong preferences for physical distancing and wearing face masks, as compared to general hygiene and respiratory etiquette. High vaccine accessibility independent of the location, receiving successive doses of the same vaccine brand and higher vaccine uptake of people in younger adults’ social circle were highly preferred. Higher preferences for mandates requiring proof of vaccination and altruistic motives focused on protecting others by getting vaccinated were associated with vaccine acceptability. As the COVID-19 pandemic waxes and wanes, studies using larger, nationally representative samples are needed to replicate and validate these results to assess preferences for health behaviors corresponding to the latest recommendations. The use of this methodology could provide public health authorities with a unique opportunity to develop targeted, preference-based messaging that aligns with the latest guidelines to effectively encourage compliance and COVID-19 vaccine uptake.

Zhu, P., Perez, S., Griffin-Mathieu, G., Tatar, O., & Rosberger, Z. (2022). What influences parents to vaccinate (or not) their sons with the Human Papillomavirus (HPV) vaccine: an examination of HPV vaccine decision-making changes over time. Journal of Psychosocial Oncology Research and Practice4(1), e068. https://doi.org/10.1097/OR9.0000000000000068

Background: Most sexually active adults are infected with the Human Papillomavirus (HPV) in their lifetime and about 3800 Canadians are diagnosed each year with a HPV attributable cancer. Although highly effective HPV vaccines exist, the HPV is responsible for 4.5% of all cancers worldwide, that include cervical, anal, vaginal/vulvar, penile, and oropharyngeal cancers. The present HPV vaccine uptake rate for boys in Canada is well below the target set by the Canadian government. This study aimed to analyze the motives that influence a change in parents’ HPV vaccine-decision-making status for their sons over time.

Methods: Data were collected using a web-based survey that measured knowledge, attitudes, beliefs, and behaviors regarding HPV vaccination. Canadian parents of boys aged 9 to 12 completed the survey at baseline (T1) and in a follow-up survey 9 months later (T2). Parents’ decision stage regarding their son receiving the HPV vaccine was categorized using the Precaution Adoption Process Model: unaware, unengaged, undecided, decided not to vaccinate, decided to vaccinate, or vaccinated. Parents who moved stages from T1 to T2 responded to open-ended questions, and we used qualitative deductive and inductive methods to analyses data. In parallel, we used quantitative methods to analyses parents’ knowledge, attitudes, and beliefs. Results of quantitative and qualitative analyses were compared and interpreted.

Results: Of the 1427 parents who completed the survey at both T1 and T2, 118 parents moved to decided not to vaccinate, 125 moved to decided to vaccinate, and 9 to vaccinated. Qualitative analyses revealed that parents who moved to decided not to vaccinate their son indicated harms, knowledge, and general anti-vaccination attitudes as the top categories for vaccine nonacceptability. These parents also scored lower on HPV and HPV vaccine knowledge scales. Benefits, knowledge, and hearing positive opinions from health care professionals (HCPs) were the most commonly assigned categories for parents who moved to decided to vaccinate their sons.

Conclusions: Highlighting the benefits of the vaccine, countering negative stories about the vaccine, and having HCPs provide strong recommendations are critical to increase HPV vaccine uptake in boys.

Shapiro, G. K., Tatar, O., Knäuper, B., Griffin-Mathieu, G., Rosberger, Z. (2022) The impact of publicly funded immunization programs on human papillomavirus vaccination in boys and girls: An observational study. The Lancet Regional Health – Americas. 100128. https://doi.org/10.1016/j.lana.2021.100128

Background: Reaching and maintaining high global human papillomavirus (HPV) vaccine uptake has been challenging. The impact of publicly funded HPV immunization programs and the interplay of sociodemographic, psychosocial and policy factors in maximizing vaccination is poorly understood. This observational study examined the impact of introducing publicly funded school-based HPV vaccination programs for boys directly on uptake in boys and indirectly on uptake in girls, while concurrently examining other important sociodemographic and psychosocial factors.

Methods: Data were collected from a national, longitudinal sample of Canadian parents of children aged 9–16 years during August-September 2016 (T1) and June-July 2017 (T2). Participants completed an online questionnaire measuring sociodemographic characteristics, vaccine knowledge and attitudes, health care provider recommendation, and HPV vaccine uptake. Analyses were conducted separately for parents of boys and girls using logistic regression analyses at T1 and T2. Jurisdictions with HPV vaccine funding for boys at both time-points were compared to those with funding at neither time-points and those that introduced funding between time-points.

Findings: The sample included parents of boys (n = 716) and girls (n= 843). In multivariable analyses, jurisdictions with funding for boys at both time-points had higher odds of vaccination (adjusted odds ratio, T1 = 10.18, T2 = 11.42; 95% confidence interval, T1 = 3.08–33.58, T2 = 5.61–23.23) than jurisdictions without funding at both time-points; however, funded jurisdictions did not have higher odds of vaccination compared to jurisdictions that newly introduced funding for boys. Vaccination was associated with consistent determinants in boys and girls including child’s age, health care provider recommendation, perceived vaccine harms, and perceived vaccine affordability.

Interpretation: This gender-sensitive analysis highlights the interplay of sociodemographic, psychosocial, and policy factors that can improve HPV vaccination. Publicly funded school-based programs are an impactful strategy to increase vaccine uptake.

McBride, E., Tatar, O., Rosberger, Z., Rockliffe, L., Marlow, L. A., Moss-Morris, R., Kaur, N., Wade, K., & Waller, J. (2020). Emotional response to testing positive for human papillomavirus at cervical cancer screening: a mixed method systematic review with meta-analysis. Health Psychology Review, 1-35. https://doi.org/10.1080/17437199.2020.1762106

Tens-of-millions of women every year test positive for human papillomavirus (HPV) at routine cervical screening. We performed a mixed-methods systematic review using a results-based convergent design to provide the first comprehensive overview of emotional response to testing positive for HPV (HPV+). We mapped our findings using the cognitive behavioural framework. Six electronic databases were searched from inception to 09-Nov-2019 and 33 papers were included. Random-effects meta-analyses revealed that HPV+ women with abnormal or normal cytology displayed higher short-term anxiety than those with normal results (MD on State-Trait Anxiety Inventory = 7.6, 95% CI: 4.59–10.60 and MD = 6.33, CI: 1.31–11.35, respectively); there were no long-term differences. Psychological distress (general/sexual/test-specific) was higher in HPV+ women with abnormal cytology in the short-term and long-term (SMD = 0.68, CI: 0.32–1.03 and SMD = 0.42, CI: 0.05–0.80, respectively). Testing HPV+ was also related to disgust/shame, surprise and fear about cancer. Broadly, adverse response related to eight cognitive constructs (low control, confusion, cancer-related concerns, relationship concerns, sexual concerns, uncertainty, stigma, low trust) and six behavioural constructs (relationship problems, social impact, non-disclosure of results, idiosyncratic prevention, indirect clinical interaction, changes to sexual practice). Almost exclusive use of observational and qualitative designs limited inferences of causality and conclusions regarding clinical significance.

Tatar, O., Wade, K., McBride, E., Thompson, E., Head, K. J., Perez, S., Shapiro, G.K., Waller, J., Zimet, G., & Rosberger, Z. (2020). Are health care professionals prepared to implement human papillomavirus testing? A review of psychosocial determinants of human papillomavirus test acceptability in primary cervical cancer screening. Journal of Women’s Health29(3), 390-405. https://doi.org/10.1089/jwh.2019.7678

Background: Guidelines for cervical cancer screening have been updated to include human papillomavirus (HPV) testing, which is more sensitive compared to cytology in detecting cervical intraepithelial neoplasia. Because of its increased sensitivity, a negative HPV test is more reassuring for a woman that she is at low risk for precancerous cervical lesions than a negative Pap test. Prompted by the inadequate translation of HPV test-based screening guidelines into practice, we aimed to synthesize the literature regarding health care providers (HCPs) knowledge, attitudes, and practices related to HPV testing and the influence of psychosocial factors on HCPs acceptability of HPV testing in primary cervical cancer screening.

Materials and Methods: We searched MEDLINE, Embase, PsycINFO, CINAHL, Global Health, and Web of Science for journal articles from January 1, 1980 to July 25, 2018. A narrative synthesis of HCPs knowledge, attitudes, and practices related to HPV testing is provided. Informed by the Patient Pathway framework, we used deductive thematic analysis to synthesize the influence of psychosocial factors on HCPs acceptability of HPV testing.

Results: The most important HCP knowledge gaps are related to the superior sensitivity of the HPV test and age-specific guideline recommendations for HPV testing. Thirty to fifty percent of HCPs are not compliant with guideline recommendations for HPV testing, for example, screening at shorter intervals than recommended. Barriers, facilitators, and contradictory evidence of HCPs’ acceptability of the HPV test are grouped by category: (1) factors related to the HCP; (2) patient intrinsic factors; (3) factors corresponding to HCP’s practice environment; and (4) health care system factors.

Conclusions: HCP’s adherence to guidelines for HPV testing in cervical cancer screening is suboptimal and could be improved by specialty organizations ensuring consistency across guidelines. Targeted educational interventions to address barriers of HPV test acceptability identified in this review may facilitate the translation of HPV testing recommendations into practice.

Tatar, O., Shapiro, G. K., Perez, S., Wade, K., & Rosberger, Z. (2019). Using the precaution adoption process model to clarify human papillomavirus vaccine hesitancy in canadian parents of girls and parents of boys.  Human vaccines & immunotherapeutics, 15: 7-8, 1803-1814. https://doi.org/10.1080/21645515.2019.1575711

Background: Achieving optimal human papillomavirus (HPV) vaccine uptake can be delayed by parents’ HPV vaccine hesitancy, which is as a multi-stage intention process rather than a dichotomous (vaccinated/not vaccinated) outcome. Our objective was to longitudinally explore HPV related attitudes, beliefs and knowledge and to estimate the effect of psychosocial factors on HPV vaccine acceptability in HPV vaccine hesitant parents of boys and girls.

Methods: We used an online survey to collect data from a nationally representative sample of Canadian parents of 9–16 years old boys and girls in September 2016 and July 2017. Informed by the Precaution Adoption Process Model, we categorized HPV vaccine hesitant parents into unengaged/undecided and decided not. Measures included sociodemographics, health behaviors and validated scales for HPV and HPV vaccine related attitudes, beliefs and knowledge. Predictors of HPV vaccine acceptability were assessed with binomial logistic regression.

Results: Parents of boys and girls categorized as “flexible” hesitant (i.e., unengaged/undecided) changed over time their HPV related attitudes, behaviors, knowledge and intentions to vaccinate compared to “rigid” hesitant (i.e., decided not) who remained largely unchanged. In “flexible” hesitant, greater social influence to vaccinate (e.g., from family), increased HPV knowledge, higher family income, white ethnicity and lower perception of harms (e.g., vaccine safety), were associated with higher HPV vaccine acceptability.

Conclusions: HPV vaccine hesitant parents are not a homogenous group. We have identified significant predictors of HPV vaccine acceptability in “flexible” hesitant parents. Further research is needed to estimate associations between psychosocial factors and vaccine acceptability in “rigid” hesitant parents.

Shapiro, G. K., Tatar, O., Dube, E., Amsel, R., Knauper, B., Naz, A., Perez, S., & Rosberger, Z. (2018). The vaccine hesitancy scale: Psychometric properties and validation. Vaccine36(5), 660-667. https://doi.org/10.1016/j.vaccine.2017.12.043

Introduction: The SAGE Working Group on Vaccine Hesitancy developed a vaccine hesitancy measure, the Vaccine Hesitancy Scale (VHS). This scale has the potential to aid in the advancement of research and immunization policy but has not yet been psychometrically evaluated.

Methods: Using a cross-sectional design, we collected self-reported survey data from a large national sample of Canadian parents from August to September 2016. An online questionnaire was completed in English or French. We used exploratory and confirmatory factor analysis to identify latent constructs underlying parents’ responses to 10 VHS items (response scale 1–5, with higher scores indicating greater hesitancy). In addition to the VHS, measures included socio-demographics items, vaccine attitudes, parents’ human papillomavirus (HPV) vaccine decision-making stage, and vaccine refusal.

Results: A total of 3779 Canadian parents completed the survey in English (74.1%) or French (25.9%). Exploratory and confirmatory factor analysis revealed a two-factor structure best explained the data, consisting of ‘lack of confidence’ (M = 1.98, SD = 0.72) and ‘risks’ (M = 3.07, SD = 0.95). Significant Pearson correlations were found between the scales and related vaccine attitudes. ANOVA analyses found significant differences in the VHS sub-scales by parents’ vaccine decision-making stages (p < .001). Independent samples t-tests found that the VHS sub-scales were associated with HPV vaccine refusal and refusing another vaccine (p < .001). Socio-demographic differences in the VHS were found; however, effect sizes were small (η2 < 0.02).

Conclusions: The VHS was found to have two factors that have construct and criterion validity in identifying vaccine hesitant parents. A limitation of the VHS was few items that loaded on the ‘risks’ component and a lack of positively and negatively worded items for both components. Based on these results, we suggest modifying the wording of some items and adding items on risk perceptions.

Shapiro, G. K., Tatar, O., Amsel, R., Prue, G., Zimet, G. D., Knauper, B., & Rosberger, Z. (2018). Using an integrated conceptual framework to investigate parents’ HPV vaccine decision for their daughters and sons. Preventive medicine116, 203-210. https://doi.org/10.1016/j.ypmed.2018.09.017

Despite being an effective cancer prevention strategy, human papillomavirus (HPV) vaccination in Canada remain suboptimal. This study is the first to concurrently evaluate HPV vaccine knowledge, attitudes, and the decision-making stage of Canadian parents for their school-aged daughters and sons. Data were collected through an online survey from a nationally representative sample of Canadian parents of 9–16 year old children from August to September 2016. Measures included socio-demographics, validated scales to assess HPV vaccine knowledge and attitudes (using the Health Belief Model), and parents’ HPV vaccination adoption stage using the Precaution Adoption Process Model (PAPM; six stages: unaware, unengaged, undecided, decided not, decided to, or vaccinated). 3779 parents’ survey responses were analyzed (1826 parents of sons and 1953 parents of daughters). There was a significant association between child’s gender and PAPM stage of decision-making, with parents of boys more likely to report being in earlier PAPM stages. In multinomial logistic regression analyses parents of daughters (compared to sons), parents of older children, and parents with a health care provider recommendation had decreased odds of being in any earlier PAPM stage as compared to the last PAPM stage (i.e. vaccinated). Parents who were in the ‘decided not to vaccinate’ stage had significantly greater odds of reporting perceived vaccine harms, lack of confidence, risks, and vaccine conspiracy beliefs. Future research could use these findings to investigate theoretically informed interventions to specifically target subsets of the population with particular attention towards addressing knowledge gaps, perceived barriers, and concerns of parents.

Perez, S., Zimet, G. D., Tatar, O., Stupiansky, N. W., Fisher, W. A., & Rosberger, Z. (2018). Human papillomavirus vaccines: successes and future challenges. Drugs78(14), 1385-1396. https://doi.org/10.1007/s40265-018-0975-6

Over a decade has passed since the first human papillomavirus (HPV) vaccine was introduced. These vaccines have received unequivocal backing from the scientific and medical communities, yet continue to be debated in the media and within the general public. The current review is an updated examination that the authors made five years ago on some of the key sociocultural and behavioral issues associated with HPV vaccine uptake and acceptability, given the changing HPV vaccine policies and beliefs worldwide. We explore current worldwide HPV vaccination rates, outline HPV vaccine policies, and revisit critical issues associated with HPV vaccine uptake including: risk compensation, perceptions of vaccine safety and efficacy, age of vaccination, and healthcare provider (HCP) recommendation and communication. While public scrutiny of the vaccine has not subsided, empirical evidence supporting its safety and efficacy beyond preventing cervical cancer has amassed. There are conclusive findings showing no link that vaccinated individuals engage in riskier sexual behaviors as a result of being immunized (risk compensation) both at the individual and at the policy level. Finally, HCP recommendation continues to be a central factor in HPV vaccine uptake. Studies have illuminated how HCP practices and communication enhance uptake and alleviate misperceptions about HPV vaccination. Strategies such as bundling vaccinations, allowing nurses to vaccinate via “standing orders,” and diversifying vaccination settings (e.g., pharmacies) may be effective steps to increase rates. The successes of HPV vaccination outweigh the controversy, but as the incidence of HPV-related cancers rises, it is imperative that future research on HPV vaccine acceptability continues to identify effective and targeted strategies to inform HPV vaccination programs and improve HPV coverage rates worldwide.

Tatar, O., Thompson, E., Naz, A., Perez, S., Shapiro, G. K., Wade, K., Zimet, G., Gilca, V., Janda, M., Kahn, J., Daley, E., Rosberger, Z. (2018). Factors associated with human papillomavirus (HPV) test acceptability in primary screening for cervical cancer: A mixed methods research synthesis. Preventive medicine116, 40-50. https://doi.org/10.1016/j.ypmed.2018.08.034

Primary screening for cervical cancer is transitioning from the longstanding Pap smear towards implementation of an HPV-DNA test, which is more sensitive than Pap cytology in detecting high-risk lesions and offers greater protection against invasive cervical carcinomas. Based on these results, many countries are recommending and implementing HPV testing-based screening programs. Understanding what factors (e.g., knowledge, attitudes) will impact on HPV test acceptability by women is crucial for ensuring adequate public health practices to optimize cervical screening uptake. We used mixed methods research synthesis to provide a categorization of the relevant factors related to HPV primary screening for cervical cancer and describe their influence on women’s acceptability of HPV testing. We searched Medline, Embase, PsycINFO, CINAHL, Global Health and Web of Science for journal articles between January 1, 1980 and October 31, 2017 and retained 22 empirical articles. Our results show that while most factors associated with HPV test acceptability are included in the Health Belief Model and/or Theory of Planned Behavior (e.g., attitudes, knowledge), other important factors are not encompassed by these theoretical frameworks (e.g., health behaviors, negative emotional reactions related to HPV testing). The direction of influence of psychosocial factors on HPV test acceptability was synthesized based on 14 quantitative studies as: facilitators (e.g., high perceived HPV test benefits), barriers (e.g., negative attitudes towards increased screening intervals), contradictory evidence (e.g., sexual history) and no impact (e.g., high perceived severity of HPV infection). Further population-based studies are needed to confirm the impact of these factors on HPV-based screening acceptability.

Perez, S., Tatar, O., Gilca, V., Shapiro, G. K., Ogilvie, G., Guichon, J., Naz, A., & Rosberger, Z. (2017). Untangling the psychosocial predictors of HPV vaccination decision-making among parents of boys. Vaccine35(36), 4713-4721. https://doi.org/10.1016/j.vaccine.2017.07.043

Background: HPV vaccination uptake in boys is suboptimal in many jurisdictions, particularly in the absence of publicly funded HPV vaccination programs. Parents represent key decision-makers of HPV vaccination and their HPV vaccine decision-making stage is influenced by multiple psychosocial determinants. Our objective was to assess the relationship between a broad range of psychosocial factors and parents of boys’ HPV vaccine decision-making stage.

Methods: Data were collected through an online survey from a nationally representative sample of Canadian parents of boys in February (T1) and November 2014 (T2). We assessed a broad number of psychosocial factors including: socio-demographics, health behaviours and validated scales for assessing HPV knowledge, attitudes and beliefs. Parents selected their HPV vaccination adoption stage based on the Precaution Adoption Process Model (PAPM). Multinomial logistic regression was used to test the association between predictors and PAPM stage at T1 and T2.

Results: Discussion with a healthcare provider about the HPV vaccine and increased HPV knowledge was associated with increased odds of being in the more advanced PAPM stages. Increased perception of risks in the absence of HPV vaccination, increased perception that others endorse HPV vaccination and positive attitudes related to vaccines in general were associated with increased odds of being in the decided to vaccinate stage. Believing that HPV vaccination is harmful increased, and perceiving the benefits of HPV vaccination decreased the odds of deciding not to vaccinate.

Conclusions: This study highlights the psychosocial predictors of the decision-making stage reported by parents regarding HPV vaccination of their sons, that were significant at two time-points. Targeted interventions that consider the impact of the health care provider and address knowledge gaps as well as individual beliefs about benefits, risks, and harms of the HPV vaccine and vaccines in general should be implemented to help parents make better informed decisions that is, to move closer to actual vaccination adoption.

Perez, S., Tatar, O., Ostini, R., Shapiro, G. K., Waller, J., Zimet, G., & Rosberger, Z. (2016). Extending and validating a human papillomavirus (HPV) knowledge measure in a national sample of Canadian parents of boys. Preventive medicine91, 43-49. https://doi.org/10.1016/j.ypmed.2016.07.017

As the human papillomavirus (HPV) vaccine is now recommended for males, a reliable, comprehensive HPV knowledge measurement tool which addresses issues relevant to males is needed. We aimed to replicate, validate and test the comprehensiveness of an existing general HPV and an HPV vaccination knowledge scale in English and French. We also measured parental HPV knowledge and changes over time. An online questionnaire was administered in February (Time 1; T1) and November 2014 (Time 2; T2) to a nationally representative sample of Canadian parents of boys. Dimensionality, internal consistency and model fit were evaluated at both time points and separately in English and French sub-samples. Differences in knowledge scores were measured. Analyses were performed on 3117 participants at T1 and 1427 at T2. The 25-item HPV general knowledge and an 11-item HPV vaccination scale were unidimensional, showed high internal consistency (α > 0.87, α > 0.73) and had good model fit. Both general HPV and vaccine-specific knowledge significantly increased over time in both languages, but remained low at T2, with only about half of the items being answered correctly. Correct responses at T2 are best explained by correct responses at T1, with some small changes from ‘Don’t know’ at T1 to correct at T2. The extended general and vaccine-specific knowledge scales are valid, reliable and comprehensive, and could be used among parents of boys, in both English and French. Educational interventions could target specific knowledge gaps and focus on providing information rather than correcting misconceptions.

Perez, S., Shapiro, G. K., Tatar, O., Joyal-Desmarais, K., & Rosberger, Z. (2016). Development and validation of the human papillomavirus attitudes and beliefs scale in a National Canadian sample. Sexually transmitted diseases43(10), 626-632. https://doi.org/10.1097/OLQ.0000000000000506

Background: Parents’ human papillomavirus (HPV) vaccination decision-making is strongly influenced by their attitudes and beliefs toward vaccination. To date, psychometrically evaluated HPV vaccination attitudes scales have been narrow in their range of measured beliefs and often limited to attitudes surrounding female HPV vaccination. The study aimed to develop a comprehensive, validated and reliable HPV vaccination attitudes and beliefs scale among parents of boys.

Methods: Data were collected from Canadian parents of 9- to 16-year-old boys using an online questionnaire completed in 2 waves with a 7-month interval. Based on existing vaccination attitudes scales, a set of 61 attitude and belief items were developed. Exploratory and confirmatory factor analyses were conducted. Internal consistency was evaluated with Cronbach’s α and stability over time with intraclass correlations.

Results: The HPV Attitudes and Beliefs Scale (HABS) was informed by 3117 responses at time 1 and 1427 at time 2. The HABS contains 46 items organized in 9 factors: Benefits (10 items), Threat (3 items), Influence (8 items), Harms (6 items), Risk (3 items), Affordability (3 items), Communication (5 items), Accessibility (4 items), and General Vaccination Attitudes (4 items). Model fit at time 2 were: χ2/df = 3.13, standardized root mean square residual = 0.056, root mean square error approximation (confidence interval) = 0.039 (0.037–0.04), comparative fit index = 0.962 and Tucker-Lewis index = 0.957. Cronbach’s αs were greater than 0.8 and intraclass correlations of factors were greater than 0.6.

Conclusions: The HABS is the first psychometrically-tested scale of HPV attitude and beliefs among parents of boys available for use in English and French. Further testing among parents of girls and young adults and assessing predictive validity are warranted.