Guarding Patient Confidentiality: Finland’s Innovative Study Investigates Safe Use of Real-World Data

by | Nov 5, 2023

Finland’s data authority, Findata, has recently implemented a strong anonymization framework to protect patient privacy while effectively using real-world data (RWD). This framework, which includes advanced techniques like k-anonymity and e-differential privacy, is a groundbreaking initiative that combines clinical trial data with RWD in a unique study on the effectiveness of oral anticoagulant medications in atrial fibrillation (AF) patients. The ultimate goal is to revolutionize evidence-based medicine.

To protect patient privacy, the anonymization process began by setting a k-anonymity threshold at k=5. This threshold ensures that individual patient data cannot be easily re-identified, providing a strong safeguard for privacy. Findata’s approval of this level demonstrates their commitment to protecting patient confidentiality.

Additionally, an e value of 3.46 was chosen to enhance privacy, finding a balance between data utility and privacy risk. This e-differential privacy criterion guarantees strong privacy protections for the anonymized RWD, aligning with Findata’s strict requirements.

The study incorporates PACIFIC-AF phase II clinical trial data and RWD from various Finnish healthcare registries. By focusing on patients aged 45 and above who were prescribed novel oral anticoagulant medication between January 2014 and September 2019, the study specifically targets a population with diagnosed AF. The outcomes of these patients are compared to those from the clinical trial arm, providing valuable insights into the real-world effectiveness of these medications.

To ensure comparability between the RWD and clinical trial data, sophisticated matching and weighting techniques are used. Researchers accurately match patients in the clinical trial arm to those in the RWD cohort by estimating the propensity score (PS) through a logistic-regression model. These matching weights are determined based on the predicted probability of receiving or not receiving the treatment, ensuring a fair comparison.

After the matching and weighting process, the methodology’s success is assessed through descriptive statistics. Standardized mean differences (SMDs) below 0.1 indicate a successful matching process, ensuring the RWD cohort is comparable to the clinical trial arm.

The anonymization process involves transforming the RWD based on variable types and privacy criteria. Categorical variables, including quasi-identifying variables, are subjected to an exponential differential privacy mechanism. This method adds noise to the data, protecting individual privacy while maintaining the overall integrity of the dataset. Numerical variables are anonymized using the Laplace mechanism, further preserving patient confidentiality.

To enhance patient privacy, the order of anonymized records is shuffled, and subject identifiers are replaced by random record identifiers. These additional steps ensure the identities of patients involved in the study remain secure.

The resulting anonymized RWD provides a comprehensive and privacy-preserving dataset for analysis. Researchers can explore various outcomes, including overall survival, by tracking patients from study entry until a death event or censoring at the end of 2020. These insights contribute to a greater understanding of the safety and efficacy of novel oral anticoagulant medications in real-world settings.

Throughout the study, Findata’s approval and oversight play a crucial role in ensuring the ethical use of RWD. By implementing strict anonymization measures, Findata upholds its commitment to protecting patient privacy while advancing medical research. This combination of clinical trial data and RWD sets a new benchmark for future research.

The Finnish study shows the importance of balancing data utility and patient privacy. By using robust anonymization frameworks and adhering to data protection regulations, researchers can leverage the power of real-world data while preserving patient confidentiality.

As healthcare embraces the potential of RWD, it’s crucial for stakeholders to prioritize patient privacy and data protection. Findata’s pioneering efforts in Finland provide a blueprint for other countries and organizations seeking to responsibly and ethically use real-world data.

In conclusion, Finland’s implementation of an anonymization framework ensures the privacy and security of patient data in a groundbreaking study. By combining clinical trial data with RWD, researchers gain valuable insights into the safety and efficacy of novel oral anticoagulant medications. This study sets a high standard for data protection and privacy preservation in healthcare research, emphasizing the importance of responsible data use in advancing medical knowledge. With the successful integration of real-world data and stringent privacy measures, Finland’s approach paves the way for transformative advancements in evidence-based medicine.