Human papillomaviruses (HPV), a diverse group of small DNA viruses that primarily target the mucosal and epidermal squamous epithelium, leading to benign warts and malignant tumors in the anogenital region and upper respiratory and digestive tracts (1). Specifically, high-risk HPV subtypes are instrumental in the development of various pathologies, including oropharyngeal malignancies, cervical cancer, male genital tumors, and dermatological conditions like condyloma acuminatum (2). Contemporary epidemiological assessments posit that roughly 2.8 billion women aged 15 years and onward are at potential risk for cervical cancer initiation (3). In China, with its substantial population, there are approximately 106,000 new cases of cervical cancer and 48,000 fatalities annually, constituting over 28% of the worldwide cases of this disease (4). Furthermore, the incidence of HPV-associated head and neck cancers is escalating swiftly across China, and it is projected that HPV-positive oropharyngeal cancer cases will exceed cervical cancer cases within the next 15–20 years (2).

Nonetheless, for a set of malignancies with a well-established etiology (5), comprehensive clinical investigations have underscored that prophylactic vaccination before initial sexual exposure ensures efficacy against the designated HPV strains (6). Subsequent to the 2006 endorsement of the HPV vaccine in the United States, over 100 nations have formally adopted it into their respective national immunization schedules (7). Unfortunately, due to public concerns over the safety and risk of harm from vaccinations, vaccine coverage rates are slowly declining in developed nations (8). In alignment with the “Accelerated Eradication of Cervical Cancer” initiative advanced by the World Health Organization (WHO), several cities within mainland China have commenced pilot HPV immunization programs for adolescent girls from 2020 onwards (9). Similarly, due to the lack of vaccine accessibility for adult females and parental concerns regarding the safety of vaccines, the current HPV vaccination rate in China is considerably low, at less than 6% of the overall population (10). In the landscape of HPV vaccination, clinical interns represent a distinctive cohort, encompassing the forthcoming cadre of physicians, nurses, pharmacists, and other primary healthcare professionals. They are at the forefront of advancing public health responsibilities, playing a crucial role in the promotion and popularization of HPV vaccination (2). Numerous studies have demonstrated that healthcare professionals are the primary providers of vaccinations, and individuals are more likely to get vaccinated following their recommendation (11, 12). Notably, clinical interns are also within the age group most at risk for HPV infection (13). As the HPV vaccine becomes increasingly available in China, understanding and elevating the vaccine uptake intentions among this demographic is critical. Despite the increasing spread of HPV vaccination, a noticeable gap remains in the literature regarding the vaccine’s acceptance among Chinese clinical interns. Consequently, this study seeks to evaluate the vaccination intentions of Chinese clinical interns and to identify the critical factors influencing these intentions.

Earlier research has identified a range of factors influencing HPV vaccine acceptability in the general population, including knowledge about the vaccine, perceptions of its safety, and accessibility to vaccination (2, 12, 13). However, for this specific cohort, relying solely on descriptive research methodologies may not sufficiently probe the underlying reasons for vaccine acceptability. The Theory of Planned Behavior (TPB) is a well-established model in social psychology, delineating the relationship between individuals’ intention and their resultant behaviors (14). It postulates that an individual’s behavior is influenced by their intention, which is shaped by attitude towards the behavior, subjective norms, and perceived control over the action (15). Previous research findings have indicated that within the TPB framework, attitudes, subjective norms, and perceived control are positively associated with behavioral intentions (3, 16). Furthermore, TPB is adaptable, and Ajzen suggests that it can be adapted to incorporate additional variables (15). In the expanded framework of the TPB, additional psychosocial constructs such as media engagement, HPV risk and vaccination perceptions, descriptive norms, and anticipated regrets have been incorporated to assess their influence on the intent to get the HPV vaccine (4, 14, 15). Moreover, Rajeh et al. (16) augmented the TPB model by adding perceived knowledge as a predictive variable for oral health behavior intentions. Beyond the core components of the TPB model, health knowledge related to HPV will serve as potential determinants influencing vaccination intentions in this study. As a result, this study includes perceptual knowledge into the model and employs Structural Equation Modeling (SEM) to analyze the effectiveness of the extended TPB model in explaining clinical interns’ intentions to receive the HPV vaccine, thereby providing a more comprehensive theoretical support and predictive capability.

This study extensively investigates the determinants influencing HPV vaccine uptake intentions among clinical interns in China, utilizing elements of the TPB model and extended factors such as HPV-related health knowledge. Our findings emphasize the significant roles of TPB’s core components—attitudes, subjective norms, and perceived behavioral control—in forming vaccination intentions. Concurrently, HPV-related health knowledge, as a vital independent variable, plays a crucial role in influencing the vaccination decisions of clinical interns. Additionally, the study examines the potential impact of demographic factors on vaccination intentions. These insights provide important perspectives for understanding and promoting HPV vaccination among future healthcare professionals.

The research indicated that subjective norms are the most significant determinant of clinical interns’ intentions to vaccinate against HPV, corroborating earlier TPB-based studies on vaccination intent predictions (20, 23, 24). Within the TPB framework, subjective norms refer to an individual’s perception of how significant others view their behavior, reflecting the importance of social approval in decision-making (15). For clinical interns, this suggests they may particularly value the opinions of peers, mentors, and authoritative health organizations. Their perspectives not only reflect societal endorsement but also represent the professional standards and expectations they aspire to as newcomers to the medical profession. In this context, clinical interns’ perceptions of what is socially approved are influenced by the information they access, making it evident that the quality and accessibility of information significantly contribute to their vaccination decisions (25). Reinforcing positive attitudes and information about the HPV vaccine in medical education and professional training can enhance interns’ willingness to vaccinate as they build their professional identities (25).

Additionally, our study observed a significant positive correlation between Perceived Behavioral Control (PBC) and the intention to receive the HPV vaccine, aligning with the expectation that higher perceived self-efficacy and stronger subjective norms typically enhance the intention to engage in specific behaviors (15). However, this finding contrasts with studies from certain regions in the United States. For instance, a study conducted within the framework of the TPB in Alabama found no correlation between PBC and university students’ intentions to vaccinate HPV (20). Similarly, a study in Arizona reported that immunizing pharmacists and pharmacy interns scored lower on perceived subjective norms compared to other TPB constructs (23). This discrepancy is primarily reflected in the United States’ introduction of the HPV vaccine for females in 2006 and the implementation of a gender-inclusive HPV immunization policy in 2011 (26), significantly enhancing vaccine uptake and economic accessibility. This policy provides the general population, especially adolescents and young adults, with low-cost or free vaccination channels through public health projects or health insurance. Such a strategy effectively reduces the barriers to vaccine administration, potentially diminishing the influence of PBC on the intention to vaccinate. Conversely, in China, despite increasing public awareness of the HPV vaccine, its non-inclusion in the national immunization schedule and the necessity for out-of-pocket payment (3), along with limited vaccination sites, may heighten the barriers related to cost and accessibility. In order to make HPV vaccination more accessible and affordable for a wider population, collaboration and communication among relevant stakeholders are indispensable (25). This collaboration should involve healthcare institutions, government agencies, and public health organizations. Their collective efforts, including the implementation of policies aimed at offering more extensive vaccination support and effectively addressing obstacles to vaccine acceptance, will play a pivotal role in expanding vaccination centers and mitigating the economic challenges associated with vaccination. Among the TPB variables, attitude was identified as the weakest predictor of the intention to receive the HPV vaccine, indicating that the interns’ intentions are less influenced by their personal evaluations and feelings towards the vaccine. This phenomenon could stem from the fact that as novices in the medical profession, their decision-making is more driven by professional standards and medical education guidance (2), rather than merely personal emotional preferences.

Prior research from various nations has consistently revealed that groups with more comprehensive knowledge about HPV, including students of different ages (27, 28), parents of adolescents (29, 30), and men and women from various age groups (31, 32), tend to show a stronger inclination towards vaccination. Despite this, there has been a scarcity of studies exploring the link between these two factors within the TPB framework. To address this gap, our study incorporated “knowledge” as an additional variable in the TPB model to investigate its influence on clinical interns’ intentions to receive the HPV vaccine. The findings indicated a positive correlation between the interns’ intentions to get vaccinated and their understanding of HPV health issues. This implies that clinical interns, who have acquired a more in-depth comprehension of HPV and its vaccine through their medical education (13), are likely to give more weight to preventive measures. Moreover, their direct involvement in patient care enhances their focus on disease prevention, which in turn further solidifies the transition from knowledge to the intention to vaccinate. In light of these findings, it is recommended to further enhance public health and preventive medicine curricula, with a particular focus on comprehensive training about HPV and its vaccines (33, 34). Teaching hospitals should organize targeted health promotion activities, such as workshops and lectures, aimed at increasing medical trainees’ awareness of the importance of HPV vaccination. Korkidi et al. (35) also underscored the crucial role of health education in the effective execution of HPV vaccine strategies, particularly in enhancing societal awareness and consciousness of HPV prevention.

This research notably shows that specific demographic attributes significantly influence the inclination towards HPV vaccination. Specifically, clinical interns with higher family monthly income and those who have been involved in handling HPV-related cases exhibited a stronger intention to receive the HPV vaccine. In China, due to the specifics of medical education and training programs, intern medical students are typically not considered official employees of their respective hospitals, and they usually do not receive a salary (36), leading to a lack of financial independence. Additionally, the cost of HPV vaccination in China is relatively high, with prices for imported vaccines ranging from approximately RMB 1,800 ($270 USD) to RMB 3,900 ($580 USD), while domestic vaccines are priced at about RMB 1,000 ($150 USD) (37). In this study, the majority of the interns’ family monthly incomes were below RMB 8,000 ($1,100 USD), making the cost of vaccination a significant economic consideration. Consequently, it was observed that interns from families with higher monthly incomes demonstrated a markedly stronger intention to get vaccinated against HPV, clearly highlighting the close relationship between family economic status and vaccination intentions. Additionally, we also observed that clinical interns with experience in handling cases related to HPV exhibited a stronger inclination towards HPV vaccination. This trend may be attributed to the direct involvement of medical practitioners in managing HPV-related cases during their clinical practice (38), leading to a deeper understanding of HPV’s infection pathways and its potential health threats. Such firsthand experience enhanced their knowledge of the efficacy of HPV vaccination, resulting in a higher willingness to opt for vaccination compared to their peers who had not directly handled similar cases. Therefore, during the internship period, it is recommended that teaching hospitals prioritize placing interns in departments that handle HPV cases, enabling students to better comprehend the infection pathways of HPV and its impact on health. While we found a clear link between family economic status and HPV vaccination intentions, as well as a direct correlation with clinical experience with HPV, it is notable that other demographic variables such as gender did not present significant associations in our analysis. The findings stand in contrast to previous reports by Chen et al. (39), which highlighted gender-based differences in HPV vaccination willingness, and López et al. (40), which identified female gender as a significant determinant of vaccine acceptability. This may be indicative of the clinical intern group’s unique characteristics, where their professional identity and practical medical exposure could overshadow the influence of traditional demographic factors. It underscores the need for future studies to explore the multifaceted influences on health behavior intentions within varied demographic contexts.

Our study also has some limitations. Firstly, the study’s exclusive focus on the Shandong region impacts the diversity of its participants. Considering the significant variations in educational resources, medical practices, economic conditions, and cultural norms across different regions of China, the findings might not fully represent the actual situation in other areas of the country. Moreover, only a small proportion of respondents (0.7%) were over the age of 25. This demographic homogeneity limits the generalizability of our findings across a broader age range and to individuals outside the medical industry. Consequently, the specialized knowledge of our respondents about vaccines may not be representative of the general population’s awareness or attitudes towards HPV vaccination. Future research could build upon this by extending its scope to include a more diverse array of participants, thus enabling comparative studies across a broader spectrum of perspectives. Secondly, the cross-sectional design of the study, while useful for identifying correlations between variables, is limited in establishing causality. Additionally, the use of self-reported data might lead to biases like social desirability or recall bias, potentially impacting the precision of the findings. Lastly, while the expanded TPB model offers valuable insights, it lacks integration with components from other behavior change theories, such as the Transtheoretical Model and the Health Belief Model. Future research should consider integrating elements from these and other behavioral theories to enrich the understanding of HPV vaccination intentions among clinical interns.

This study is among the few worldwide to focuses on the HPV vaccine uptake intentions among clinical interns, representing a pioneering exploration in this field within China. By utilizing the extended theory of planned behavior model, this research highlights the pivotal roles of attitudes, subjective norms, perceived behavioral control, and HPV-related health knowledge in shaping vaccine intentions. Considering the crucial role of future medical professionals in promoting public health and vaccine advocacy, the insights from this study are essential for national authorities in formulating vaccination policies and play a significant role in guiding medical education and training in teaching hospitals.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving humans were approved by The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial QianFoshan Hospital. The studies were conducted in accordance with the local legislation and institutional requirements. Written informed consent for participation in this study was provided by the participants' legal guardians/next of kin. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.

HW: Writing – original draft. YX: Writing – review & editing, Data curation, Formal analysis, Project administration. HZ: Supervision, Writing – review & editing. NC: Data curation, Writing – review & editing.