Parental perspectives: a mixed method study on perceived risk, self-efficacy, vaccine response efficacy, and willingness for adolescent HPV vaccination in Puducherry, South India

Study design and setting

A community-based explanatory mixed-method study was conducted from March 2023 to March 2024 among the parents of adolescent girls aged 9–18 years in 4 selected villages in the rural and urban field practice areas (defined geographical region where populations access services from designated health centres) of a Tertiary Care Centre in Puducherry. The field practice area has two Primary Health Centres (PHCs) providing preventive and curative services to the population of 8 villages. The PHCs operate under the guidance of a Medical Officer and Senior residents from the Department of Preventive Medicine and Social Medicine, with coordination by Junior Residents, Public Health Nurses, Auxiliary Nurse Midwives (ANM), and Accredited Social Health Activists (ASHA). Presently, health centres are focused on screening women over 30 for cervical cancer and conducting educational sessions to increase awareness about Cervical cancer.

Ethical approval and consent

The study was conducted after obtaining permission from the Institutional Ethics Committee (IEC approval number – JIP/IEC-OS/2023/079). Informed written consent was obtained from participants who are 18 years and above, while assent was obtained from participants aged 15–17 years before data collection in the local language. Confidentiality was maintained throughout the data collection process.

Operational definitions

1. Risk-perception: Risk perception is the subjective assessment of the characteristics and severity of a risk, as well as the perceived risks of HPV-related cancers

2. Self-efficacy: Confidence in one’s ability to prevent HPV infection without vaccination, i.e., How confident one can prevent being infected with HPV now and in the future without vaccinating against HPV.

3. Vaccine response-efficacy: Confidence in the vaccine’s ability to prevent HPV infection; It is measured as the perceived ability of the vaccine to prevent HPV infection.

Study population

The study population included parents of adolescent girls (9–18 yrs) who had resided in the field practice area for at least six months. Unwilling parents, those who did not provide written informed consent, were excluded from the study.

Sample size and sampling technique

The sample size was calculated based on an assumption of 50 % prevalence for the willingness of adolescents to undergo HPV vaccination, with a 95 % confidence level and 5 % absolute precision. This resulted in an initial sample size estimate of 384 participants, with half of the sample (192 participants) being collected from the urban and rural field practice areas.

A multistage random sampling technique was employed. In the first stage, two villages with larger adolescent populations were purposively selected from a list of eight villages within the urban and rural field practice areas. A line listing of all eligible adolescent girls was created using the registers maintained at the respective PHCs. The selected urban and rural PHCs had 544 and 305 eligible adolescent girls, respectively. Adolescents were then randomly selected from the line list using a lottery method and contacted their parents for the study. If parents could not be contacted after two attempts, they were removed from the list and new parents were selected using the lottery method, ensuring no replacement of previously selected participants.

For the qualitative component of the study, 10 interviews were conducted. These included five key informant interviews (KIIs) with healthcare workers (medical officers, public health nurses, and senior residents) and five in-depth interviews (IDIs) with adolescent girls and their parents [18], 34].

Quantitative component

A pre-tested, structured interviewer-administered questionnaire was used for face-to-face interviews. The tool’s face and content validity were verified by a panel of three experts with relevant experience. It was translated into Tamil and pre-tested among 20 eligible parents outside the study settings. This semi-structured questionnaire consisted of 52 questions across four sections, including socio-demographic and health-seeking behaviour, knowledge regarding cervical cancer and HPV vaccination among the study participants (Questionnaire is available in Supplementary file 1).

During data collection, parents were approached at home. If multiple adolescent girls were present in the family, parents would provide information about the elder adolescent. The study procedure was explained, and informed consent was obtained before data collection. Following this, after assessment of the baseline knowledge regarding cervical cancer and HPV vaccination; a brief education session on them was provided, and then data such as i) perceived risk, self-efficacy, and vaccine response efficacy, and ii) willingness to vaccinate were collected. Responses of ‘yes’ were coded as 1, and ‘no’ was coded as 0. Based on expert opinion, each question was assigned a specific weight, and the weighted averages were calculated. The summed responses were divided into three categories, representing low, moderate, and high.

Qualitative component

A semi-structured interview guide (Supplementary file 2) was developed based on quantitative phase findings and all six Health Belief Model (HBM) [23] domains. The guide contained open-ended questions exploring factors influencing HPV vaccination willingness, barriers and facilitators of HPV vaccination, perceived cervical cancer risk, self-efficacy, and vaccine response efficacy among adolescent girls and parents, while examining healthcare worker challenges and expectations.

Participants who are vocal and willing were selected purposefully. 10 interviews were conducted: five key informant interviews with healthcare providers and five in-depth interviews with adolescent girls and their parents in the regional language. All interviews conducted in private areas were recorded with their consent, lasting 15–20 min each. Participants reviewed summary points post-interview to ensure information accuracy.

Quantitative analysis

Quantitative data was collected using Epicollect 5, and statistical analysis was performed using IBM SPSS version 23.0 software after adjusting for all missing values. Perceived risk, self-efficacy, and vaccine response efficacy were expressed in frequency and proportions with 95 % confidence intervals (CI). The associations between perceived risk, self-efficacy, vaccine response efficacy and willingness to vaccinate were analysed using the Chi-squared test based on the expected frequency and summarised as Odds Ratio with 95 % C.I. The associations between socio-demographic factors, health-seeking behaviour, and willingness to vaccinate were analysed using univariate regression and the crude Prevalence ratio (cPR) was estimated. The variables with a p-value of less than 0.20 were included in the multivariable log-binomial regression analysis, an adjusted Prevalence ratio (aPR) was estimated, and p-value <0.05 was considered statistically significant.

Qualitative analysis

Interviews were conducted and translated into English by the principal investigator. Audio recordings were transcribed verbatim within one week of data collection to prevent information loss. Manual descriptive analysis was performed to generate codes, which were organised into categories and further grouped into sub-themes and overarching themes (categorisation available in Supplementary file 3). The Health Belief Model framework was utilised to develop sub-themes and overarching themes (Figure 1).

Figure 1:

Conceptual model – HPV vaccine acceptance and coverage among adolescent girls.

Socio-demographic characteristics

All 388 approached participants were available and consented to participate in the study, thus all were included in the analysis. The majority were mothers (94.8 %), mostly under 45 years old (86.3 %). Among adolescent girls, 51.8 % were aged 15–18 years. Most participants were Hindu (89.9 %) and lived in a nuclear family (69.8 %). Regarding education, about half of mothers (47.7 %) and fathers (49.5 %) had completed high school. Among the adolescent girls, 21.9 % were pursuing graduation, while 22.4 % were in higher secondary and middle school. The majority (76 %) held a red ration card, indicating lower economic status, and 66 % lacked health insurance. Fathers were mostly employed (93.3 %), while half of mothers (50.1 %) were employed and 61.9 % of households had four members or fewer (Table 2).

Risk perception, self-efficacy, vaccine response

In the study population, 44.8 % of parents perceived high risk. When stratified by age groups, parents of early adolescents (ages 9–14) have a higher risk perception at 50.8 % compared to parents of late adolescents (ages 15–18) at 39.3 %. Nearly half of the parents (49.0 %) reported low self-efficacy, while a substantial majority (70.9 %) expressed confidence in the HPV vaccine’s effectiveness.

The majority of parents (91.5 %) were willing to vaccinate their adolescent daughters in government facilities,

I think only experienced doctors are available at government hospitals. So, I trust government hospitals and the medicine they provide, more than private hospitals. I will accept more if the vaccine is provided by the government – Adolescent Girl Mother (AGM)

While 44.1 % expressed willingness in private facilities, with half (41.8 %) willing to pay more than INR 2000 (Table 1).

I asked about this vaccination to the doctor in a nearby private hospital, but the rate of that injection is very high, so I haven’t vaccinated my daughter till now – AGM

Since nearly 90 % would vaccinate if available in government facilities, analysing associations with willingness in that context would yield minimal additional value. Additionally, HPV vaccination in India is currently only accessible through private facilities. Therefore, all association analyses were restricted to assessing willingness to vaccinate in private healthcare facilities.

The association of sociodemographic factors with parents’ willingness to vaccinate their adolescent daughters against HPV, after adjusting for other factors, showed that higher maternal education levels were significantly associated with increased willingness to vaccinate. Compared to mothers with primary or middle school education, those with high school (aPR=4.4, 95 % CI: 1.3–14.3, p=0.016), higher secondary (aPR=3.9, 95 % CI: 1.0–15.8, p=0.049), and graduation or above (aPR=6.2, 95 % CI: 1.5–26.3, p=0.013) showed higher adjusted prevalence ratios for willingness to vaccinate. Fathers with graduation or higher education had a significantly lower adjusted prevalence ratio for willingness to vaccinate (aPR=0.2, 95 % CI: 0.0–0.7, p=0.014) compared to illiterate fathers (Table 2).

Risk perception, self-efficacy, vaccine response and their willingness to vaccinate

The association analysis revealed that parents with high perceived risk had 13 times higher odds of willingness to vaccinate their daughters compared to those with the least perceived risk (OR=13.9, 95 % CI: 8.3–24.4, p<0.001).

I believe in this vaccination because I’m afraid that in future, once I contract cervical cancer, I can’t avail of vaccination, so it is better to prevent it early by getting the vaccination – Adolescent Girl(AG)

Parents with low self-efficacy showed stronger association with willingness to vaccinate (OR=8.9, 95 % CI: 4.7–17.6, p<0.001).

I think that there is no need of vaccines, because I’m healthy, and I’m good. If I vaccinate there is chance to get some problems, so better not to vaccinate- AGM

Similarly, parents with a high perception of vaccine response efficacy, compared to those having moderate perception were significantly more likely to be willing to vaccinate their daughters (OR=5.7, 95 % CI: 3.3–10.2, p<0.001) (Table 3).

I have belief on vaccinations I was very confident I had given all known vaccines for my child from childhood onwards, so my kid is good and healthy, I was in Chennai(metropolitan city), so I know about all vaccines, I think this vaccine is also safe like that- Adolescent Girl Mother

Health seeking behaviour

Regarding the health-seeking behaviour of the participants, 88.1 % of parents consulted healthcare workers for urinary tract infections, while 61.3 % sought advice from doctors in the past year. However, 76.5 % of the parents had not undergone cervical cancer screening. While all adolescent girls received compulsory immunisations under the universal schedule, only 6.7 % received optional vaccines. Moreover, 82.7 % of the parents were fully vaccinated against COVID-19. However, awareness about HPV was limited, with only 6.2 % having heard about it and 12.5 % aware of its association with cervical cancer. Additionally, only 8.2 % were aware of the availability of a cervical cancer vaccination (Table 4).

Health care provider perspectives on risk perception and vaccine response efficacy among beneficiaries

Healthcare providers were interviewed to understand their views on how communities perceive health risks and respond to vaccines, based on their experience working with vaccination programs in the field. The quantitative findings showed that 78.1 % of respondents had heard about cervical cancer, primarily from Accredited Social Health Activists/Auxiliary Nursing Midwives (Healthcare providers at the community level in India) (41.9 %), television/newspapers (31.6 %), and doctors (16.5 %).

Healthcare providers identified significant knowledge gaps among parents and community members regarding HPV and cervical cancer. As one gynaecologist noted:

Their (parents) level of knowledge will be very low. First, I think there is a need to make them aware that the HPV infection causes cervical cancer. I don’t think they even know about it.

Public health nurses highlighted how vaccine availability affects their ability to provide education and also emphasised that community acceptance increases when people understand disease risks.

We are not giving awareness about HPV vaccination to prevent cervical cancer. because that vaccine is not available in the government supply; if it is available, then only we can conduct awareness among the public- Public Health Nurse (PHN)

There is a lack of felt need for this vaccination because they are unaware of the importance and burden… we know that the COVID vaccination rate has improved with the knowledge everyone is susceptible to the disease. uptake increased after the second wave, after a lot of deaths occurred. I felt the need for awareness is more important – PHN