The registry protocol was approved by the Ethics Committee of the University of Rosario (CEI-UR) in February 2024 (Bogotá, Colombia) (No. 2541-CV1830). The protocol of this registry complies with national regulations (Law 23 of 1981 and Resolution 8430 of 1993 of the Ministry of Health of Colombia) and international regulations (which include the Treaty of Helsinki, CIOMS International Ethical Guidelines for Biomedical Research in Human Beings and the Taipei Declaration).

The researchers acknowledge that this project falls under the category of health databases, as defined by the Declaration of Helsinki, involving the collection of patient data beyond routine clinical care. Consequently, the OVAR adheres to the ethical guidelines outlined in the Declaration of Taipei, which governs health databases and biobanks.

OVAR was designed as a retrospective investigation. Given the nature of this study, obtaining specific informed consent for research is not planned. Since no interventions or modifications will be made to patient care and the data collected retrospectively will be managed in strict accordance with confidentiality guidelines governing the use of clinical records, the Research Ethics Committee was requested to waive the requirement for informed consent. This waiver will enable access to conduct the necessary documentary review, limited to the data specified in this protocol and solely for academic research purposes.

In Colombia, as in the world, diagnosis of OC is made in late stages due to the absence of specific symptoms of this disease, therefore, the need to characterize clinically and histopathological these patients to optimize the diagnosis and treatment, is born to describe these clinical aspects will allow us to understand the better clinical particularities of this disease.

The patients to be included in the registry must have the following requirements: (i) Colombian women of legal age, treated at the Hospital Universitario Mayor Méderi (Bogotá, Colombia). (ii) Patients diagnosed with OC, International Classification of Diseases (CIE10), C56X and C482, determined from January 1, 2021. Who has the marker CA125 and diagnostic confirmation by anatomopathological study (reported in clinical history or pathology laboratory). (iii) Patients who, due to their condition, are under management by the gynecologic-oncology service of Méderi.

Note: The diagnosis doesn't need to be made intra-hospital, if it has the diagnostic information mentioned in point two of the case definition.

The gyneco-oncology staff will identify the cases and oversee entering the data of the detected patients into a list system previously established in the institution. This base will be refined to generate a list where only patients who meet the case definition will be present for their subsequent entry to the registry. The leading group of the registry will send the list of patients to the digitizer to review medical records. The data will be obtained exclusively from the following sources: the electronic medical record systems Servinte®, Xerox, and Annarlab. Figure 1 represents the process from the entry of patients into the registry to collecting all the proposed information.

Study data were collected and managed using REDCap electronic data capture (EDC) tools hosted at Hospital Universitario Mayor Méderi. REDCap (Research Electronic Data Capture) ( https://project-redcap.org/) ^{10, 11} is a secure, web-based software platform designed to support data capture for research studies, providing 1) an intuitive interface for validated data capture; 2) audit trails for tracking data manipulation and export procedures; 3) automated export procedures for seamless data downloads to common statistical packages; and 4) procedures for data integration and interoperability with external sources ( Table 1).

A bivariate analysis will explore potential relationships between variables, employing the Pearson X ² test to compare clinical characteristics with histopathology. Categorical variables will be described as frequencies, proportions or percentages using a relative risks model. For continuous variables (age, tumor size), measures of central tendency (mean, median) and dispersion (standard deviation, range) will be used depending on whether the data are normal. Most of the statistical analysis will be performed using the statistical package R-4.4.3 ( https://www.r-project.org/). Management of absent data: The presence of missing data for these variables will be evaluated and, if necessary, simple imputations (mean or mode) will be applied.

To characterize the sample size, a descriptive analysis will be performed where continued variables with a normal distribution will be represented by their mean and SD and non- normal distributions will be represented by their median and IQR.

T-tests or ANOVA will compare mean values across groups (e.g., age differences among various histological types). At the same time, logistic regression will assess the associations between clinical and histopathological characteristics.

The findings from this registry will result in an article published in an internationally indexed journal, contributing new knowledge that may benefit the global scientific and academic community in this field. Furthermore, the results will be presented at an academic event to further disseminate this knowledge among scientific associations, researchers, professional societies, healthcare institutions, universities, and academic organizations.

The systematization of the registered variables information is currently underway, ensuring data organization and quality for subsequent analysis.

The realization of this work complies with the national regulations (Law 23 of 1981 and Resolution 8430 of 1993 of the Ministry of Health of Colombia) ^{12, 13} and international (which include the Treaty of Helsinki, CIOMS International Ethical Guidelines for Biomedical Research in Human Beings and the Taipei Declaration). Biomedical research in humans should be carried out only by qualified scientists under the supervision of a competent medical professional (art. 395). It cannot be carried out legitimately unless the importance of its objective is proportionate to the risk that runs the subject of Experimentation (art. 396).

According to the nature and design of the records, no closing date of collection is stipulated. If completion of registration is considered for internal reasons of the leading group of the registry that prevents continuity to the maintenance of data collection over time, the Registry Leader will issue a letter notifying Centro de Investigaciones de Méderi (CIMED) and CEI-UR, indicating the reasons for completing the registration. Accordingly, the information will continue to be stored on the physical servers of the hospital for 15 years, counted from the date of entry of the last registration and by Resolution 839 of 2017. ¹⁴

For the leading group of the registry, having approval from the OVAR does not exempt from submitting to evaluation and approval by the CIMED and the CEI-UR any research protocol that requires as input the total or partial information of this registry, following the regular conduit already known. The research protocols derived from the registry will be built by researchers and CIMED and CEI-UR will independently analyze the risks and benefits of research protocols according to their specific particularities. The team responsible for the registry responds to the reports or follow-up meetings requested by the research center or the entity that requires them. The team will make no modifications to the registration protocol without the prior approval of CIMED and the endorsement of the ethics committee.

By Law 23 of 1981, Chapter I, Article 1. ¹² The leaders of the registry are clear that having this protocol approved does not exempt submission and other ethical responsibilities of the research protocols that use this registry as input.

The members of the registry will sign confidentiality agreements with the institution to keep the information confidential. It is guaranteed that no information will be stored in any source other than that provided for this purpose (Redcap). Internal and external audits will be conducted to ensure the quality of the information record.

The leading group of the registry is committed to ensuring that all research protocols utilizing data from the Ovarian Cancer Registry are based on strong ethical principles, supported by rigorous scientific and methodological foundations. These protocols will incorporate a clear social component, and objective to provide direct or indirect benefits to patients and their families. Access to the sequenced information will only be granted with the approval of CIMED and CEI-UR.

The protocol, participant-level dataset, and statistical code will be made available upon reasonable request to promote transparency and scientific collaboration. Access will be granted following the approval of the corresponding ethics committees and in compliance with data protection regulations, ensuring the confidentiality and privacy of participant information. Data sharing agreements will be established as needed to safeguard ethical and legal considerations.