2.1 Quality in healthcare

According to the World Health Organization (WHO), the World Bank Group (WB) and the Organization for Economic Cooperation and Development ^{(OECD) (2019)}, quality of care can be defined as the degree to which health services for individuals and populations increase the likelihood of desired health outcomes and are consistent with current professional knowledge (p. 30). This implies that process improvement in healthcare settings should be aligned with the interests of users and communities as key stakeholders.

Taking this into consideration, many programs and accreditation schemes have been proposed to implement and maintain quality management systems in the field of clinical laboratory services. Out of many accreditation schemes currently available, the ISO 15189 is the most widely used standard to ensure quality in clinical laboratories worldwide (^{Datema, Oskam & Klatser, 2011}; ^{Zima, 2017}). Hence, it is employed in the present research article to assess the quality accreditation status of clinical laboratories in Costa Rica.

2.1.1 Clinical laboratory ISO 15189 accreditation

Since the decade of 1970s, the adoption of quality management systems became an increasingly common practice among clinical laboratories. However, laboratory professionals (especially from the European community) considered that existing standards such as the ISO 17025 and the Essential Criteria of the European Communities Confederation of Laboratory Medicine fell short to the necessity of ensuring quality throughout the whole process cycle within a clinical laboratory: from pre-analytical to post-analytical stages (^{Thelen & Huisman, 2018}).

Consequently, a technical committee was installed by the International Standardization Organization (ISO), which drew upon the requirements of existing standards (e.g. ISO 17025, ISO 9001, Essential Criteria of EC4, the British Clinical Pathology Accreditation program, among others) and adjusted them to the context of a clinical laboratory so that equal attention was paid to pre-analytical, analytical and post-analytical processes. This led to the development and publication of the ISO 15189:2003 standard, titled Medical laboratories Requirements for Quality and Competence (^{Thelen & Huisman, 2018}).

Thanks to the existence of such international standard since the early 2000s, harmonization of quality schemes across countries was facilitated as laboratories could reach out to their countrys respective national accreditation body to include ISO 15189 in their scope. In the case of Costa Rica, the homologue version of the standard was first published some years later, with INTE/ISO 15189:2008 being the first version of the norm of which record is kept in the country. Currently, there is a second version in force, INTE/ISO 15189:2014, which is based on the international standards 2012 version (^{Instituto de Normas Técnicas de Costa Rica (INTECO], 2014}).

Regarding implementation of the standard in Costa Rica, the CCSS authorities have provided guidance for public clinical laboratories to meet a series of requirements in order to facilitate the accreditation process. These requirements are divided into four phases: a first phase covering regulatory aspects such as the registration of the laboratory before the College of Microbiologists and Clinical Chemists of Costa Rica (CMQC) and the operating permit granted by the Ministry of Health of Costa Rica. In addition, this phase contains other aspects such as: managing documentation related to authorized tests, registration of complaints or suggestions, continuous improvement processes, among others (^{CCSS, 2012}).

The second phase is mainly aimed at the development of documentation and compliance with the requirements according to the ISO 15189 standard. The third phase comprises a large part of the requirements of the standard, focused on the matter of production: equipment, reagents and various supplies. Finally, the fourth phase focuses on the full implementation of the quality management system throughout the laboratory (^{CCSS, 2012}).

As for the private sector, implementation of a quality management system in accordance to ISO 15819 relies on the willingness and capabilities of each organization to carry out such a process. Each laboratory needs to outline its own path, which ought to be aligned with the organizations structure, goals, resources and potential benefits to obtain from the process (^{Antúnez & Murillo, 2014}).

Since factors to be taken into consideration for ISO 15189 accreditation may vary from one setting to another, this can influence the ability of certain types laboratories or located within certain geographies, to create, maintain and improve a robust quality management system. This, in turn, might lead to an unequitable landscape where high quality services are only available to small population groups. In such a scenario, we would be talking about health disparities in the access to healthcare of quality.

2.2 Health disparities

Health inequalities or health disparities are differences that exist among specific population groups in the attainment of full health potential. Disparities can exist across many dimensions, such as gender, ethnicity, sexual orientation, age, disability status, socioeconomic status, and geographic location (^{Weinstein et al., 2017}).

Actually, one of the most consistent findings in the health disparities literature is that location matters. Less populated or more geographically-isolated communities may face difficulties with recruiting and sustaining an adequate healthcare workforce because of factors such as resource limitations, provider shortages, among others (^{Giraldi, García, Kundu & Famitangco, 2018}).

This has shown to be true for clinical laboratory services as well. In the United States, for instance, states with many rural areas have less clinical laboratory technologists and technicians than states with fewer rural areas (^{Giraldi et al., 2018}, p. 41). These inequalities have also been evidenced across Latin America, with laboratory services being one of the diagnostic capabilities that are in often shortage relative to demand in rural or lower income regions (^{Roa et al., 2020}). If equal access to services in general remains a challenge, more even so is this a pending challenge with regard to access to healthcare of quality.

For this reason, detecting and assessing these disparities in healthcare is of major relevance given that the only way to properly address the issue of inequality is by understanding the overall landscape as well as its underlying factors. With the methodology we describe below, we look forward to shedding some light on the topic in order to raise awareness on the current state of quality of clinical laboratory services throughout Costa Rica.

3.1 Experimental design

The current research was carried out following a quantitative approach with a descriptive scope. The study design is cross-sectional, given that secondary data on clinical laboratory registration and accreditation status was analyzed for a single time point (January 2021). Since the data consisted of secondary, anonymous, aggregate and public statistics, consent from individual organizations or a confidentiality commitment form was not necessary.

3.2 Population

The study unit for the present investigation was the clinical laboratory. Data was analyzed at a population level, without recurring to any sampling methods, given that the total number of clinical laboratories in Costa Rica was taken into account. Laboratories included were those with an operation permit by the CMQC and categorized as either Clinical Laboratory or Clinical Laboratory and Blood Bank.

Facilities whose permit category was beyond a clinical scope were excluded from the study. The following are examples of excluded settings: commercial establishments (laboratory reagent and equipment vendors), food and water microbiology laboratories, specialized laboratories, biohazardous waste management facilities, breast milk banks and transfusional units.

Regarding accreditation status, only clinical laboratories accredited as per the INTE/ISO 15189:2014 standard were included. ISO 17025-accredited or ISO 9001-certified institutions or organizations accredited by any other program were excluded from the analysis.

3.3 Data collection techniques

Data regarding clinical laboratory registration and ISO 15189 accreditation in Costa Rica were gathered from two official sources: the CMQC, which holds the database of all registered clinical laboratories allowed to operate in the country, and the list of accredited laboratories by the Costa Rican Accreditation Body (Ente Costarricense de Acreditación, ECA).

3.4 Data analysis

The aforementioned information was arranged by province -Costa Ricas main administrative divisions- and later utilized to calculate normalized indicators on the basis of population and territorial area. Reference data for these two parameters was obtained from the Costa Rican Census and Statistics Institute (^{Instituto Nacional de Estadística y Censos, (INEC], 2011}). Such indicators were calculated by dividing the number of registered (or accredited) laboratories within a province by the respective population or area. To facilitate interpretation, indicators are presented as laboratories/100 000 population and laboratories/100 km2.

Furthermore, national averages were calculated for each indicator alongside with range and standard deviation as measures of dispersion. Descriptive comparisons were made between provinces and with respect to national values.

4.1 Discussion

As mentioned before, equal access to health services of high quality is a goal to which Costa Rica has committed through the SDGs. However, the scenario pictured in this researchs results might indicate that considerable challenges are still ahead.

For instance, the first set of data to be highlighted is the number of clinical laboratories accredited nationwide. Only four clinical laboratories have been accredited in compliance with INTE/ISO 15189:2014 (the current version of the international standard for Costa Rica). All of these laboratories are located in the province of San José (Figure 1). From a descriptive point of view, this translates into a low proportion of accredited establishments (approximately 0,8%) relative to the total, which, at the same time, are geographically concentrated in a single province.

This does not necessarily mean that the rest of (non-accredited) laboratories are unable to provide health care of quality, specifically services related to clinical laboratory analyses. However, it does imply that the large majority of clinical laboratories in Costa Rica have not yet demonstrated their competence for performing clinical examinations or assays, in accordance to international standards.

In fact, the scope of the 15189 standard is defined as follows: This International Standard can be used by medical laboratories in developing their quality management systems and assessing their own competence. It can also be used for confirming or recognizing the competence of medical laboratories by laboratory customers, regulating authorities and accreditation bodies (^{ISO, 2012}). Hence, this reaffirms its importance as an objective and internationally recognized parameter for assessing quality in a specific healthcare setting, either by patients or health authorities.

Being aware of the standards aforementioned relevance, ^{Carboni-Huerta and Sáenz-Flor (2019)} carried out a survey on laboratory accreditation throughout Latin America some time ago. Our results for Costa Rica are in line with their findings for the whole region: the number of ISO 15189-accredited laboratories remains low, and it is even lower among public (state-owned) laboratories. When inquired about the reasons for their non-accredited status, most of the surveyed laboratories in the region agreed on two major factors: that laboratories current conditions do not comply with the standards requirements and that potential benefits of accreditation do not outweigh the costs (^{Carboni-Huerta & Sáenz-Flor, 2019}).

In the face of the current situation of only a small number of laboratories being accredited in Costa Rica, we conducted an additional analysis including all settings registered before the CMQC as clinical laboratories and blood banks (entities registered exclusively as blood banking facilities were excluded). Although not as drastically evident as the accreditation analysis, Table 1 reflects that density of laboratories -both by population and by territory extension- can vary between provinces.

With some exceptions (such as Puntarenas high ratio of public/state-owned laboratories per 100 000 population), an overall trend can be observed among most registered clinical laboratories: the density of these facilities is higher in central provinces of the country. This can be seen specially San José and Heredia, where there are between 10,6 and 12,8 laboratories per 100 000 population and the ratio per 100 km2 of territory oscillates around 2,1 and 4,3. On the contrary, coastal provinces such as Limón and Puntarenas exhibit lower laboratory density ratios.

Even though inferring disparity or inequity in access to health care goes beyond the scope of the methodology employed in this research, it is worth providing some context from previous literature. For example, a 2004 study by Rosero-Bixby (the only one available on the topic) demonstrated that, even after the implementation of the health sector reform (which is started in the late 20th century), Costa Rican provinces of Guanacaste, Puntarenas and Limón had the highest proportion of population with poor access to health services in general (^{Rosero-Bixby, 2004}).

Adding to this, the importance of quality clinical laboratory services for public health has been acknowledged for years. A multilateral regional precedent was set by African countries with the Maputo Declaration which, among other statements, included the governments recognition of the need to expand and further develop quality-assured laboratory services as part of a greater framework of health system strengthening within resource-limited settings (^{WHO – Regional Office for Africa, 2008, p. 1}).

According to such statement, low-, middle- and mid-high-income countries should invest in quality assurance for clinical laboratories in order to help driving the whole health systems advancement in terms of quality of care. To this, we would add that the demonstration of competence in delivering high quality services (i.e. accreditation) should be set as a priority as well. Along this line of thought, the remaining ~99% of laboratories registered in Costa Rica face an important challenge ahead.

As a final point in this discussion, it should be highlighted that this study faced some limitations regarding the level of granularity of publicly available information. Future research should inquire about differences in laboratory density at the administrative sub-division level (canton or district). Moreover, analyzing the degree of progress of laboratories currently seeking accreditation could also be a valuable contribution that would allow for a better understanding of the landscape of quality in clinical laboratory services in Costa Rica.

Lastly, findings presented here are descriptive in nature. Subsequent studies should consider the possibility of addressing the topic of disparities and/or inequity in access to laboratory health services with appropriate methodological designs that allow for a more in-depth analysis.