## 5 Qualitative Analysis
### Blockchain-Based AI Use Cases  
This section describes the use cases of blockchain-based systems and their positive impact on the AI applications that operate on them. The immutable ledger and decentralized nature of blockchain improve data integrity and security in various domains and are essential for AI applications that rely on trusted input data. In healthcare, blockchain ensures the secure exchange of patient data and improves AI-assisted diagnostics while maintaining patient privacy. AI systems in education benefit from the protection of sensitive student data through blockchain. To combat fake news, blockchain helps verify the authenticity of content, prevents manipulation, and promotes accountability. In financial services, blockchain's immutable record of transactions provides the transparent and verifiable data required for AI-powered fraud detection. In supply chains, the traceability of blockchain enables AI-assisted detection of counterfeit products while maintaining sustainable and ethical practices. In the public sector, secure, tamper-proof data storage via blockchain is essential, especially for sensitive information such as the biometric data of refugees, for AI applications that need to ensure data integrity and protect individual rights. In healthcare, cybersecurity and ethics are linked, as patients can be harmed by and thus lose trust in poorly protected healthcare systems [30]. Blockchain can be used for secure, decentralized, immutable electronic medical records to prevent loss of medical data and fraud and allow secure data sharing of clinical research data [32]. Smart contracts can automate the processing of health insurance claims [32]. Blockchain technology can also be used to manage consent forms in the context of clinical trials [56]. Implementing blockchain-digital twin technology in the healthcare sector can benefit health data management and security [40]. Digital twins also allow patients to be more directly involved in monetizing their data, thus promoting self-sovereignty [40]. Blockchain helps create a complete audit trail for clinical data and facilitates compliance with data protection regulations and ethical standards [56]. The use of blockchain in the medical field facilitates the exchange of patient data between different healthcare providers and increases the quality and authenticity of medical data, which, in turn, allows AI applications in the healthcare sector to produce more accurate results [35]. Furthermore, blockchain improves remote patient monitoring by enabling secure real-time IoT-based health observation [32], which makes maintaining patient data confidentiality particularly important due to the extensive collection and transmission of sensitive health data [30]. In such scenarios, blockchain can protect patient data and help ensure that ethical standards are met when the aforementioned data are used, for example, for AI-supported real-time monitoring and decision support [53]. Blockchain, in combination with other cryptography-based technologies such as ZKPs, can contribute to the ethical processing of healthcare data by enabling AI applications to learn from sensitive healthcare data without violating patient privacy rights [52]. Blockchain can support the ethical development of AI applications in healthcare by maintaining the integrity of medical data and ensuring that consent processes are fully traceable and verifiable [56] while the risk of unauthorized data use is reduced [52]. When applying a combined approach to assess the ethical compliance of technology, blockchain-based healthcare systems that incorporate design choices such as off-chain storage of sensitive data and encryption achieve higher evaluation scores [33]. As an example, an organ transplantation use case is implemented, leveraging features such as decentralization, security, traceability, auditability, and privacy enabled by the underlying blockchain technology [43].