Vaccine hesitancy among parents of adolescents and its association with vaccine uptake

Highlights

• We found a moderate degree of vaccine hesitancy in this population.

• The PACV, as a modified hesitancy scale, failed to predict adolescent vaccination.

• Two PACV items were associated with being due for HPV after a clinical visit.

Abstract

Background

Addressing parental vaccine hesitancy may increase adolescent vaccination acceptance. However, no validated measure exists to identify parents hesitant toward adolescent vaccines.

Objective

To determine if a modified version of the Parent Attitudes about Childhood Vaccines (PACV) survey, a previously validated tool to identify parental hesitancy toward vaccines in infants, predicts adolescent vaccine uptake at office visits.

Methods

We modified the PACV for use in the adolescent setting and distributed it to a convenience sample of parents of adolescents aged 11 to 17 presenting for care at a diverse group of six pediatric practices in Oklahoma and South Carolina. We determined the vaccination status of the parents’ adolescents for 3 vaccines (Tetanus–diphtheria–acellular pertussis [Tdap], meningococcal conjugate [MCV4], and human papillomavirus [HPV] vaccines). We used Fisher's exact tests to compare vaccination status with each survey item and with an overall general hesitancy scale that we constructed.

Results

We analyzed 363 surveys. At the time of the visit, vaccination coverage was 84% for Tdap, 73% for MCV, and 45% for any dose of HPV. Thirty-nine percent of parents expressed concern about vaccine efficacy and 41% expressed concern about side effects. Forty-five percent of parents disagreed with the statement that “teens can get all of the vaccines that are due at a single visit.” Two individual items were associated with not receiving a dose of HPV vaccine that was due. The overall modified PACV score failed to predict adolescent vaccine uptake at an office visit.

Conclusion

Several individual items were associated with vaccine uptake. The cumulative modified PACV, a general measure of vaccine hesitancy, was not associated with vaccination status despite illuminating parental hesitancy. We need to better understand vaccine-specific concerns for the adolescent population.

Introduction

The Advisory Committee on Immunization Practices (ACIP) recommends that all adolescents between the ages of 11 and 18 years of age receive 2 doses of meningococcal conjugate (MCV4) vaccine, 1 dose of the adult/adolescent formulation of tetanus–diphtheria–acellular pertussis (Tdap), 3 doses of human papillomavirus (HPV) vaccine, a yearly dose of influenza vaccine, any needed catchup vaccines, and those vaccines indicated for adolescents with high-risk conditions [1], [2], [3]. According to the National Immunization Survey-Teen (NIS-Teen), the vaccination coverage of 13–17 year olds increased from 2011 to 2013 for both MCV4 and Tdap. Between 2012 and 2013, 74.0–77.8% of teens received MCV4 and 84.6–86.0% received Tdap [4], [5]. For the three-dose HPV vaccine series, the rates did not improve from 2011 to 2012 with only 33.4% of females receiving all three doses of HPV in 2012 [4], but slightly increased for 2013 to 37.6% [5]. Vaccination rates for Tdap exceed the Healthy People 2020 goal, but the MCV4 and HPV vaccine coverage rates remained below their goals.

Barriers to adolescent vaccination include the lack of central registries that permit clinicians to track individual patients, fewer visits to health care providers, limited and often incorrect parental and adolescent knowledge and understanding about vaccines and vaccine safety, and missed opportunities at well or sick visits and parental attitudes [6], [7], [8], [9], [10], [11], [12], [13]. Our recent study of NIS-Teen data reveals other barriers to vaccination, some of which are HPV vaccine specific. Notably, among parents not intending to vaccinate with HPV in the next year, the percentage of parents citing safety concerns/side effects with respect to HPV increased from 4.5% in 2008 to 16.4% in 2010, while safety concern/side effects for MCV and Tdap never reached 1%. Parents also reported additional reasons for not giving the HPV vaccine including their teen being “not sexually active” and “not an appropriate age” [14].

Clinician recommendation increases immunization delivery across ages and vaccines. Parents who are generally hesitant about vaccines may be positively influenced by a recommendation from their children's clinicians to accept immunizations [15], [16]. We were interested in evaluating an instrument to measure parental hesitancy regarding adolescent vaccine delivery. In the absence of an adolescent- specific scale, we selected the Parent Attitudes about Childhood Vaccines Survey (PACV) by Opel et al. In evaluations of the PACV, Opel et al. have demonstrated both construct and predictive validity by associating parental PACV scores with immunization status at 19 months of age [17], [18].

This study's purpose is to determine if a modified version of the PACV for use in parents of adolescents aged 11–17 years predicts adolescent vaccine uptake.