Background

Breast cancer (BC) is a global health concern and the most prevalent cancer among women worldwide(Siegel Mph et al. 2023). Higher mortality rates have been observed in poor and rural patients (Kenzik et al. 2020), along with an increased risk of late-stage diagnoses in individuals residing in high-poverty (Williams and Thompson, 2016) and lacking health insurance coverage (Obeng-Gyasi et al. 2022). Qualitative studies have also unveiled different experiences among BC patients, influenced by sociodemographic factors and religious identities (Leão et al. 2022; Moodley et al. 2018; Obeng-Gyasi et al. 2022; Wen et al. 2014). In all, opportunities for effective diagnosis and treatment of BC are associated with several social determinants of health (SDH). SDH are the conditions surrounding individuals’ birth, growth, work, living, and ageing, including a range of forces and systems that shape the circumstances of daily life (Organización Panamericana de La Salud OPS/OMS, 2009). Social inequities in health have been defined as avoidable and unfair differences between groups due to their relative social class (Organización Panamericana de La Salud, 2023; Torres-Román et al. 2023).

In Chile, BC is the second most common cancer in the country (International Agency for Research on Cancer, 2020) with a mortality rate of 10.2 per 100,000 inhabitants (Frenz et al. 2014). Despite the statistics, women are an underrepresented group in decision-making and in the oncology workforce and senior management (Ginsburg et al. 2023). This situation makes invisible the experiences and realities of women with cancer, and the burden of BC remains unequal across less-represented social groups (Barrios, 2022). Chilean studies have suggested that age (Acevedo et al. 2015; Madariaga et al. 2024), area of residence (Cabieses et al. 2022; Durán and Monsalves, 2020; Herrera Riquelme et al. 2015; Madariaga et al. 2024), type of healthcare insurance and educational level (Cabieses et al. 2022; Herrera Riquelme et al. 2015; Madariaga et al. 2024) are significant determinants of social inequities in access to diagnosis and treatment of BC. To face this problem, BC is part of the Explicit Guarantees in Health Law (GES) that establishes guarantees of opportunity, quality, and financial protection for health problems with high health impacts, including BC (Infante and Paraje, 2010). These guarantees are rights to effective access to healthcare for patients from public and private systems. Public insurance is provided by the National Health Fund (FONASA), and private insurance is managed by social security institutions (ISAPRES) (Mondschein et al. 2020). Optional complementary health insurance can be added out of pocket, with a range of financial coverage and costs. Public healthcare is organized based on the level of complexity, with the primary level representing the lowest degree of complexity. Healthcare centres interact with one another through mechanisms of referral and counter-referral (González et al, 2019). The service provider network (public and private) is not adequately integrated and often generates barriers for patients, including cancer patients (Frenz et al. 2014). Fragmented health systems, such as those in Chile and Argentina, present significant inequities exacerbated by centralization and unequal resource distribution, where wealthier populations access better services, leaving poorer groups with limited or fragmented care options (Ruano et al. 2021; Siqueira et al. 2021). Studies from countries with more integrated healthcare systems, such as Canada and Denmark, demonstrate the potential benefits of streamlined care networks and patient-centric policies, which significantly reduce barriers to timely cancer diagnosis and treatment (Rudkjøbing et al. 2012; Stone et al. 2018). In the Chilean context, despite notwithstanding legislation such as the National Cancer Plan (NCP) (Ministerio de Salud, 2018) and the National Cancer Law (NCL) (Ministerio de Salud, 2020), and healthcare advancements in BC, evidence indicates that social inequity persists (Barrios, 2022; Herrera Riquelme et al. 2015).

One model to analyze equity in access to health care is the one proposed by Tanahashi in 1978 (Adauy et al. 2013; Tanahashi, 1978). This model allows analysis of equity in access to health care by identifying specific groups with unmet needs, barriers, and facilitators in achieving effective coverage of specific diseases (Adauy et al. 2013). Tanahashi's model considers five components to achieve effective coverage: Availability, Accessibility, Acceptability, Contact, and Effective Coverage (Adauy et al. 2013; Tanahashi, 1978). Components are described in Table 1.

Table 1 Definitions of the 5 main components of the Tanahashi model to achieve equity in effective access to care (11).
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Unlike other models that focus solely on individual patient factors or healthcare outcomes, the Tanahashi model provides a framework for evaluating both systemic and personal barriers, making it ideal for this context. While other models such as Aday and Andersen’s Behavioral Model of Health Services Use (Aday and Andersen, 1974) or Levesque’s model of access to healthcare (Cu et al. 2021) offer valuable insights into healthcare access, they focus primarily on the interaction between patient behaviours and health service utilization. The Tanahashi model, by contrast, is uniquely structured to assess healthcare system capacity and performance across different components, including the physical and organizational availability of services. This is particularly relevant in the context of breast cancer care in Chile, where systemic issues like centralization of services and lack of infrastructure play a significant role in access disparities.

This study employed the Tanahashi model and the SDH framework to explore perceived inequities and barriers in access to effective diagnosis and treatment in BC patients. The unique contribution of this study lies in its application of the Tanahashi model of care alongside the SDH framework to explore the barriers faced by breast cancer patients in Chile. While previous research has highlighted inequalities in access to cancer care, few studies have provided such an in-depth qualitative exploration, incorporating both systemic and personal perspectives.

A significant knowledge gap exists regarding BC patients’ perceived barriers in diagnosis and treatment across varied socioeconomic contexts. Understanding these perceptions is crucial to addressing healthcare inequities (Adauy et al. 2013; Leão et al. 2022). Its findings can enhance the analysis of Chile’s health system, spotlight areas for enhancement, and inform future clinical strategies.

Methods

'Methods' section is structured following the consolidated criteria for reporting qualitative studies (COREQ) (Tong et al. 2007) (Supplementary File 1).

Study design

Exploratory case study design conducted under a qualitative paradigm (Vásquez Navarrete et al. 2011) to understand a little-known phenomenon. Case studies involve various sources of information to provide a detailed description of the case (Creswell, 2014). For this research, the case study was defined as the perceived barriers to reaching equity in effective access to diagnosis and treatment for BC in Chile, following the components of the Tanahashi model.

Participant selection and recruitment

The study employed a theoretical sampling strategy, which is often used in qualitative research to ensure that participants with diverse and relevant experiences are selected to address the research question comprehensively (Vásquez Navarrete et al. 2011). This strategy aimed to capture a diversity of experiences regarding access to breast cancer care, including variations based on age, region of residence, and type of health insurance. By focusing on these factors, the study sought to explore the intersection of sociodemographic and healthcare system-related barriers.

The sampling units were three: (i) women with BC (patients), (ii) health professionals (HP) who diagnose and treat BC patients, and (iii) one civil society leader (CSL) linked to BC. The inclusion of breast cancer patients ensured that the study captured firsthand experiences of navigating the healthcare system. Healthcare professionals provided insights into the systemic and operational aspects of cancer care delivery, while the civil society leader contributed perspectives on advocacy and broader social influences on healthcare access.

Sampling was purposive to achieve diversity of experiences and discourses. The goal of this sampling strategy was to capture a diverse range of experiences to fully explore equity in access to breast cancer care, and not only identify the common barriers faced by patients but also the unique challenges experienced by those in more vulnerable or underserved groups. This diversity in experiences was crucial for applying the Tanahashi model and social determinants of health framework to understand inequities in effective healthcare access.

Considering these dimensions, a theoretical minimum of 20 patients, 5 healthcare professionals and 1 civil society leader was defined which was reached during the study. The inclusion criteria for each group of participants are in Table 2. The exclusion criteria for all participants were reporting a physical or mental condition limiting the person’s ability to participate voluntarily in the study. The sample size remained flexible throughout the study, and recruitment continued until data saturation was achieved. In this context, saturation occurs when no new themes or insights emerge from additional data collection, indicating that the sample size is sufficient to capture the relevant experiences of the participants. As data collection progressed, the research team continually assessed whether additional participants were needed to capture new insights or themes, which ultimately led to the decision to conclude with 26 participants. While the sample size may appear small relative to the population of Chile, the aim was not to achieve statistical generalization but rather to explore in-depth, qualitative insights into healthcare access, particularly focusing on underrepresented voices.

Table 2 Inclusion criteria for patients, health professionals and civil society representatives.
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Recruitment was carried out between October 2021 and March 2022. It was conducted remotely because of the pandemic context. Recruitment strategies included mailing, flyers, and infographics inviting to participate in this study through contacts from several social networks and civil society organizations related to BC, and the subsequent snowball technique (38). Potential patients participants provided contact information (telephone or email) and were contacted by study coordinator. No one refused to participate. HP and CSL were recruited via email among professional networks of the researchers.

Setting

Participants filled out an online informed consent available on an encrypted platform. Individual semi-structured interviews were conducted online, taking approximately 45 min. They were conducted using Zoom, WhatsApp or Meet depending on the participant's preference. The interview was performed by CC and FV.

Technical challenges were encountered during the interview process. A common issue was unstable internet connections, particularly for participants in rural areas, which sometimes caused delays or interruptions during the interviews. Additionally, some participants were unfamiliar with the online platforms used for the interviews, resulting in initial difficulties with joining the virtual meetings or adjusting audio/video settings. To address these challenges, the research team implemented several solutions. For participants experiencing connectivity issues, the interview was paused and resumed after reconnection or an alternative platform (such as a telephone call) was used to complete the interview. To assist participants unfamiliar with online platforms, the research team provided simple, step-by-step instructions for joining the meetings. Despite the technical challenges encountered, the research team was able to conduct all interviews successfully, ensuring that participants’ experiences were captured in full. The solutions implemented helped to mitigate potential disruptions, and the remote nature of the interviews allowed for greater geographic diversity in the participant sample, enhancing the study’s findings.

Data collection

The interviewer used a flexible pre-defined script prepared by the research team based on the study’s objectives and available literature (Vásquez Navarrete et al. 2011) (Supplementary File 2). Following the SDH approach, sociodemographic data (age, health insurance, region, education) were identified. According to the Tanahashi model, perceived barriers to effective access to diagnosis and treatment of BC (availability, accessibility, acceptability, contact with service, effective coverage) were inquired. Interviews were recorded for transcription and securely stored on a personal computer.

All anonymized interviews were fully transcribed to Word and confirmed by CC and FV. Each interview was assigned a unique code to ensure participant information and confidentiality. Deductive thematic analysis, a qualitative method that allows for identifying thematic patterns from the data collected, was carried out (Vásquez Navarrete et al. 2011).

For the codification process, ATLAS.Ti software was used. Information was organised based on categories according to the Tanahashi model components (availability, accessibility, acceptability, and contact) serving as the initial framework for coding. Each interview transcript was reviewed line-by-line by FV and CC separately, and specific segments of the data were assigned codes corresponding to one or more of the components of the model. This initial round of coding helped to organise the data into broad categories based on the study’s theoretical framework. The coding process was iterative and the codes were continually refined and adjusted as new data were reviewed. This iterative approach allowed for the identification of nuanced sub-themes within the broader framework of the Tanahashi model. Throughout this process, the codes were discussed between FV and CC in a consensus-building process, where discrepancies were discussed and resolved.

Each Tanahashi component was also analysed through the lens of SDH by examining perceived differences in effective access based on age, region of residence and the type of health insurance. The research team translated the textual citations from Spanish to English for publication ensuring accurate interpretation.

Scientific rigour

Several measures were employed to ensure the quality and rigour of the data collection process. Triangulation of responses from participants (patients, HP, and one CSL) and reflexivity notes were considered (Creswell, 2014; Cypress, 2017). Triangulation was conducted and integrated with descriptive findings by CC and FV. Triangulation of data was achieved by comparing responses across patients, healthcare professionals, and civil society leaders. This approach helped identify common themes and discrepancies across different perspectives. Researcher reflexivity was a critical component of this study. Both interviewers (CC and FV) engaged in continuous self-reflection throughout the data collection process, documenting personal assumptions, values, and potential biases in reflexivity notes. Reflexivity notes were taken throughout the research project and integrated into findings during qualitative analysis, mostly in incorporating the SDH dimensions into the components of the Tanahashi model.

To minimize interviewer bias, a standardized semi-structured interview guide was used, ensuring that each participant was asked similar questions in a consistent manner. The interviewers (CC and FV) were trained in qualitative interviewing techniques, emphasizing neutrality and avoiding leading questions. Interviews were conducted with open-ended prompts, allowing participants to share their experiences freely without steering from the interviewers. Regular team discussions were conducted to critically assess these reflections and ensure that biases were minimized during the data analysis.

Results

Study participants characterisation

A sociodemographic characterisation of all participants was displayed in Table 3. Patients were from different regions, health systems, ages, and educational levels. HP were physicians from public or private health systems. The CSL was the president of a BC organisation in Chile.

Table 3 Sociodemographic characteristics of participants.
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The study identified several key themes related to barriers in accessing breast cancer care, which were categorized according to the components of the Tanahashi model.

Perceived barriers to effective access related to the availability

Participants identified two main categories related to the availability: (i) limited human resources, particularly a shortage of oncologists who mainly operate in private systems, and (ii) geographical barriers. This scarcity contributes to an unstable and inequitable care system.

'We are very few oncologists, so if an oncologist leaves a hospital or a private health institution, it destabilises the system everywhere' M1, F_PUBLIC

In terms of geographical barriers, this is firstly connected to Chile’s high centralisation of care in the Metropolitan region (Santiago), which generates significant inequities in the health infrastructure and services available between regions such as the extreme north and south of the country. People from the Metropolitan region and other regional capitals have fewer barriers than those from rural, island or distant territories. The lack of infrastructure in regions and rural areas limits the installation of advanced technologies and treatments. See quote #1 and #2 Table 4.

Table 4 Representative quotes for each barrier identified according to Tanahashi Model and SDH framework.
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This is especially severe in the public system due to the reference processes implemented between centres based on the complexity of care. Due to the lack of specialised cancer centres in some regions, patients are referred to other regions, requiring them to change their residence places. There is no consistent communication between the different institutions or support in providing patient information; therefore, patients report feeling lost, confused, or stuck in their navigation. See quote #3 Table 4.

CSL also recognise this referral system as a barrier that causes delays in health care processes, especially at the beginning of the process in patients from the public system. See quote #4 Table 4.

Perceived barriers to effective access related to limited accessibility

The perceived barriers to accessibility were related to (i) age, (ii) type of health insurance, and (iii) lack of information.

Age is a critical barrier to accessing mammography for BC suspicion. In Chile, people under 40 and over 60 are not included in the annual mammography recommendation group, making timely diagnoses difficult in young women. Mammography also presents difficulties in establishing suspicion in women who have dense breasts, which is often the case of those under 50. In these cases, a breast ultrasound can be used; however, it is not part of the free-of-charge preventive examination and requires a medical order, which makes access more difficult. See quote #5 Table 4.

Health insurance barriers were referred to: (i) bureaucratic complexities in scheduling appointments; (ii) coverage disparities between public and private systems; and (iii) differences in accessibility to multiple services. The appointment process differs significantly across health centres and between public and private sectors, posing challenges for patients unfamiliar with the system’s workings.

'That’s how my odyssey began, because before I had breast cancer, I didn’t, I’ve never gotten sick from anything, I mean, I had no idea about hospitals, I didn’t even know about the Regional Hospital…' P16_FONASA

Patients, HP and CSL also perceived differences in coverage between public and private systems. They reported that ISAPRES refuse to provide coverage for specific procedures like control MRI, ultrasound for suspicion or high-cost drugs. See quote #6 Table 4.

Some of these procedures are not covered by the GES basket. In those cases, one option is to pay out of pocket the amount requested by the private system, lodge a complaint with the Health Superintendent, and await the resolution along with the corresponding reimbursement. The second alternative is to file a complaint, await the Health Superintendent’s resolution, and proceed with the payment at the end. The last alternative results in extended therapeutic pathway times. See quote #7 Table 4.

Information barriers were identified for both health systems. These are: (i) treatment for adverse effects, (ii) mental health, and (iii) breast reconstruction surgery.

Patients often face a lack of therapeutic options for managing side effects like nausea, vomiting, pain, hair loss, physical discomfort, dehydration, and anxiety, leading them to rely on personal resources and family support for solutions. See quote #8 and #9 Table 4.

Mental healthcare is considered part of the NCP and NCL, however, patients from FONASA perceive that these actions are deficient. On the other hand, a barrier identified by HP is the difficulty in acceptance of psychological therapy by some patients from both public and private healthcare. See quote #10 and #11 Table 4. Also, patients perceive that they have better access to mental healthcare in the public system compared to the private, which is beneficial for developing coping strategies related to BC. See quote #12 Table 4.

Surgical breast reconstruction is guaranteed by the GES. Perceived barriers identified are related to waiting time and uncertainty of its results. This process is slower in the public system, and sometimes patients pay their surgery out of pocket in the private system to get it sooner. See quote #13 Table 4.

Finally, lack of information is perceived in critical aspects of the therapeutic trajectory like waiting times, health guarantees and coverage, and adverse effects during treatment. This produces unequal experiences that negatively affect those with lower levels of health information, even within the same type of health insurance. See quote #14 Table 4.

Perceived barriers to effective access related to acceptability and contact

Barriers in acceptability are perceived in relation to two main categories: (i) distrust in therapeutic indications, and (ii) limited continuity of care. In terms of distrust to therapeutic medical indications, patients perceive there is a predominance of medical decisions over the patient voice, particularly in the public health system. For example, patients expressed concern and discomfort for not having the capacity to decide and negotiate around their treatment. See quote #15 Table 4.

Limited continuity of care perceived by participants relates to (i) self-navigation around the system, (ii) delayed medical appointments, and (iii) mistreatment during billing processes. Patients oversee their own navigation around the system, without expert advice or accompaniment. This situation is more severe in patients from the public system and in those with poor health information in general and in relation to GES guarantees.

'I think there is negligence towards other patients, because if I did not insist on my oncology exams, they would not do anything to me. Because it is one as a patient who has to be insisting.' P3_FONASA

Delays in scheduled appointments are often experienced in waiting rooms. These delays are not communicated to patients, and neither apologies or explanations are provided to them. See quote #16 Table 4.

Regarding patient billing processes, the private health system does not immediately invoice the patient for hospitalizations. There is an indeterminate period during which the patient is unaware of the amount owed to the ISAPRE, and upon receiving the invoice, the patient realizes they lack the financial capacity to make the payment. See quote #17 Table 4.

Perceived barriers to effective access related to global perceptions of effective coverage

Regarding global perceptions around effective coverage, patients perceive they have received good care when the cancer is under control. In all, participants belief that patients perceived satisfaction is reported to be largely related to health outcomes. See quote #18 Table 4.

Nine areas of recommendation for improvement around global perceptions of participants around effective coverage are displayed in Table 5.

Table 5 Areas that need improvement to enhance the overall perception of healthcare delivery from the voice of participants (final component of global perception of effective coverage in the Tanahashi model).
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Discussion

This study integrated perceptions from patients, HP and CSL. Qualitative approach has been recognized in the literature as relevant for addressing health inequalities in BC (Gehlert et al. 2021; Lau et al. 2022) and this study advances in current knowledge by informing about unequal experiences in BC diagnosis and treatment based on age, region of residence and type of health insurance in a South American industrialized country.

This study explored perceived barriers to accessing effective diagnosis and treatment for BC in Chile, following the Tanahashi model´s components and some SDH. By organizing the findings according to the Tanahashi model, we were able to identify which specific aspects of healthcare access as the availability, accessibility, acceptability, or contact, present the greatest challenges for patients with BC in Chile.

The findings of this study have significant implications for healthcare policy, particularly in addressing significant and structural barriers to reach effective coverage in healthcare and equity in BC in Chile, like many other countries with fragmented health systems in Latin America and beyond (Kaler et al. 2022; Ragas et al. 2014). By identifying challenges related to geographic accessibility, healthcare infrastructure, and financial constraints, this study highlights critical areas where policy reforms are needed to improve equity in healthcare access and outcomes. National statistics on breast cancer inequities mirror the experiences shared by participants in this study (Acevedo et al. 2015; Cabieses et al. 2022; Herrera Riquelme et al. 2015; Madariaga et al. 2024). By triangulating the qualitative themes with existing quantitative data studies (Acevedo et al. 2015; Cabieses et al. 2022; Herrera Riquelme et al. 2015; Madariaga et al. 2024), this study offers a more comprehensive understanding of the barriers to breast cancer care in Chile.

Following Tanahashi´s model, most perceived barriers were around accessibility and acceptability, yet not limited to them (Adauy et al. 2013; Tanahashi, 1978). Barriers were observed in every component of care: availability, accessibility, acceptability and contact with services, hence affecting the global experience of effective coverage during diagnosis and treatment processes in BC patients. From an intersectional lens (Sibeoni et al. 2018; Veenstra, 2013), being from the public health system, having low income, be under 40 or over 60, and residing in a different region from the metropolitan region are relevant dimensions that affect the perception of barriers to effective health care in BC cancer in Chile. Findings suggest the existence of structural inequities that create unequal and persistent barriers to effective access to healthcare, which has been also recognized in other international and national research involving BC (Barrios, 2022; Durán and Monsalves, 2020; Herrera Riquelme et al. 2015). If these barriers are not resolved, the achievement of equity in access to health services in BC proposed by the 2005 health reform will not be achieved (Infante and Paraje, 2010). Also, inequities due to sociodemographic and economic aspects will be perpetuated (Organización Panamericana de La Salud, 2023). One of the most urgent policy implications emerging from this study is the need to decentralize cancer care services. Patients residing outside the metropolitan region face significant geographic and financial barriers to accessing timely care. To address this, policy reforms should focus on increasing the availability of specialized oncology services in rural areas and improving the integration of regional healthcare networks. Additionally, providing financial support to low income patients for transportation and other out-of-pocket expenses could reduce the inequities observed in the public healthcare system.

With GES there has been progress in equity, mainly in availability, however, there is still a need to advance in a process with a broader perspective that puts the patient at the centre and recognizes their preferences and knowledge. Although the GES programme provides important guarantees for breast cancer care, this study reveals gaps in its implementation, particularly in relation to accessibility and acceptability of services. For instance, the lack of coverage for certain diagnostic procedures, such as mammograms for women under 40, disproportionately affects younger patients. Policy reforms should expand GES coverage to include more comprehensive preventive care for younger women and ensure that bureaucratic delays in the public healthcare system are minimized.

The study findings are novel to the country and reveal the importance of qualitative research and participant diversity in promoting health equity in BC. Limitations related to an underrepresentation of some patients with more severe stages of BC, with aboriginal ethnic backgrounds, and identified as sexually diverse in the country, whom may experience unique barriers. Also, an exploratory, inquiring approach of the qualitative method used does not aim for establishing causal relationships, yet it informs about perceived bottlenecks that can be improved to catalyse health systems and global experience of care. Future studies might consider exploring these differences from a structural determinants approach, including gender, sexism and ageism (Ginsburg et al. 2023); from other healthcare professionals, including nurses, social workers, and administrative staff; and also delve into the relationship between clinical factors and healthcare access barriers.

Key recommendations emerge from the results. Firstly, targeted interventions are needed to address structural inequities, particularly in accessibility and acceptability components, as outlined in Tanahashi’s model. Some interventions that has proven effective are mobile cancer screening units, telemedicine platforms, and patient navigation programmes (Freeman, 2012; Greenwald et al. 2017; Khanna et al. 2024). Strengthening regional healthcare infrastructure, ensuring prompt communication of healthcare changes to patients, and fostering a patient-centric approach are crucial. Additionally, a comprehensive review of GES implementation is warranted to better align with patient needs and knowledge. These measures are vital to prevent the perpetuation of sociodemographic and economic inequities in BC care and reach equity. In conclusion, this study offers a comprehensive exploration of perceived barriers to effective BC diagnosis and treatment in Chile, using a qualitative approach incorporating diverse perspectives.

Findings underscore significant systemic challenges across Tanahashi’s model components, impacting the overall care experience. The study reveals structural inequities hindering healthcare access, reflecting global patterns in fragmented health systems. Insights gained contribute novel evidence to understanding health inequities in BC, emphasizing the value of qualitative research in informing health policy for equitable care access.

Conclusion

Barriers to effective healthcare access for women with breast cancer in Chile were identified in all components of the Tanahashi model. Barriers related to human resources, infrastructure, health coverage according to age, health insurance operation, access to information, continuity of care and mistrust were identified. In Chile, breast cancer patients from the public health system, with low income, under 40 or over 60, and who do not reside in the metropolitan region experience more barriers to accessing effective healthcare. This study demonstrated the utility and necessity of qualitative methods in comprehensive health services research. It underscores the importance of exploring the perspectives of patients and other participants to understand health problems deeply and contribute to the effectiveness of healthcare and equity.

The implication of this study is significant for the field of public health and healthcare policy, particularly in the context of breast cancer care in Chile. The findings suggest that a multi-faceted approach is needed to address the barriers to equitable access in diagnosis and treatment.