# Enhancing Healthcare Security: A Unified RBAC and ABAC Risk-Aware Access Control Approach
## 4 Implementation of Proposed Model in Healthcare Scenario
### Risk-Based Access Control Implementation
#### 4.3.1 Resource Sensitivity Risk  
As clarified earlier, user identities solely govern the permissible operations and data types accessible to them. To effectively manage resource sensitivity and enhance system flexibility, access-level attributes will be assigned to the system's users to allow for the proper control of sensitive resources they can access. Table 3 shows the risk scores allocated when comparing user roles and resource sensitivities considering various roles in the MC children's hospital scenario. Since EPR medical records are highly sensitive, the resource sensitivity was classified as either confidential or restricted.  
Nurses and doctors commonly receive an advanced access level to access confidential data. When nurses attempt to access confidential data, their risk score is set to 0.4. This measure makes it more challenging for nurses to write data (as nurses also can perform write operations), necessitating lower or no risk from other categories. However, when accessing restricted data, both nurses and doctors are assigned a risk score of 0.7, as it is normal for them to obtain such access levels. Similarly, to access restricted data, they must possess significantly low or no risk from other categories. Social workers should not have any access to confidential and restricted data. However, in some extreme cases where a social worker is granted access to such data, they must schedule an appointment specifying when and where they would access the data (otherwise, the PIP would ot be able to extract their working hours and assigned office as they are not internal users of the system). By doing so, their overall risk score will be low, allowing them limited access to confidential and restricted data.  
Police officers occupy a distinct role in the MC Children's Hospital environment, where they may occasionally require access to highly sensitive medical records as part of legal or investigative procedures. While Table 3 assigns a uniform risk score of 0.6 to both confidential and restricted resource sensitivities for police officers, this numerical equivalence does not imply equal operational access in practice. In reality, access to  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**User Role** & **Resource Sensitivity** & **Risk Score** \\ \hline Nurse & Confidential & 0.4 \\ \hline Nurse & Restricted & 0.7 \\ \hline Doctor & Confidential & 0.2 \\ \hline Doctor & Restricted & 0.7 \\ \hline Social Worker & Confidential & 0.6 \\ \hline Social Worker & Restricted & 0.8 \\ \hline Police Officer & Confidential & 0.6 \\ \hline Police Officer & Restricted & 0.6 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Resource sensitivity category and associated risk score.  
restricted data by police officers is subject to stricter procedural controls than access to confidential data. For instance, officers must submit an access request specifying the purpose, timing, and location of the access in advance. This ensures that access to restricted data is granted only when absolutely necessary and under clearly defined conditions. These operational safeguards, although not fully reflected in the quantitative score, serve to minimize unauthorized access and maintain patient privacy. The enforcement of such conditional access mirrors the protocol applied to social workers, highlighting a consistent access governance model for external or auxiliary roles.