Priority vs. Severity in the Scrum Methodology and the BioAffix Priority & Severity Calculator

In the Scrum methodology, the correct determination of the priority and severity levels of tasks and defects is vital for the success of projects. In BioAffix projects, the BioAffix Priority & Severity Calculator, a tool developed to standardize this process and ensure objective evaluation, is utilized.

The Scrum methodology provides a framework that increases flexibility and efficiency in software development processes. Within this methodology, the prioritization of tasks and defects and the determination of their severity are critically important for the success and planning of projects. In BioAffix projects, a specially developed tool called the “BioAffix Priority & Severity Calculator” is used to standardize these processes and ensure consistency.

Why was the BioAffix Priority & Severity Calculator designed?

BioAffix projects are certified at CMMI (Capability Maturity Model Integration) Level 3, and the maturity level of its processes is continuously evaluated and improved. You can review the articles we have prepared on these developed and implemented processes, titled “What is ‘Definition of Done’? How It Is Used in BioAffix Projects” and “The Calculation of Defect Ratio from a CMMI Perspective and Its Role in BioAffix Projects.”

In the R&D processes that proceed according to the CMMI perspective and Scrum methodology, it was expected that Priority and Severity values would be entered by the testing and software teams according to a brief procedure. However, during reviews conducted within the framework of CMMI Level 5 analysis, it was determined that team members generally rated both Priority and Severity values as “Medium.” A detailed study using the 5 Whys method revealed that this stemmed from the procedure for determining the values being open to interpretation. To solve this issue, we developed a calculator that performs a calculation by asking three questions to determine each value.

Priority and Severity in the Scrum Methodology

In Scrum, the correct prioritization of tasks and defects (Priority) and the determination of their seriousness (Severity) ensure that sprint planning and product deliveries are carried out on time and with high quality. Here is the role of these concepts within Scrum:

• Priority: Determines how urgent a work item is and that it needs to be addressed first. The priority level is generally related to the urgency and timing of the work. In Scrum, high-priority items are placed at the top of the Product Backlog and are tackled first in sprints.
• Severity: Determines the impact of a work item or defect on the system and how critical it is. The severity level is related to the seriousness of the defects or issues. Defects with a critical severity level require immediate intervention as they can affect the overall functioning of the system.

BioAffix Priority & Severity Calcualator

Priority Calculation

The Priority & Severity Calculator used in BioAffix projects uses three main criteria to determine the priority level of tasks:

1. Impact: The effect of the task on overall success or user experience.
   • Critical (5): The task seriously affects the entire project.
   • High (4): The task affects significant functionality.
   • Medium (3): The task affects moderate functionality.
   • Low (2): The task affects minor functionality.
   • Minimal (1): The impact of the task is negligible.
2. Urgency: How quickly the task needs to be resolved.
   • Immediate (5): The task must be resolved immediately.
   • High (4): The task should be resolved as soon as possible.
   • Medium (3): The task should be resolved in the near future.
   • Low (2): The task needs to be resolved but is not urgent.
   • Very Low (1): There is no urgency to resolve the task.
3. Complexity: How much time and resources the task requires to complete. (Note: A lower score indicates higher complexity).
   • Very High (1): The task is very complex and time-consuming.
   • High (2): The task is complex and requires a significant amount of time.
   • Medium (3): The task is moderately complex.
   • Low (4): The task is simple and requires little time.
   • Very Low (5): The task is very simple and can be done immediately.

Severity Calculation

The Priority & Severity Calculator used in BioAffix projects uses three main criteria to determine the severity level of defects:

1. Impact: The effect of a task on the overall success of the project or the user experience.
   • Critical (5): The task critically affects the entire project. Its failure would lead to a system-wide failure or block the project’s completion.
   • High (4): The task impacts a major feature or significant functionality.
   • Medium (3): The task impacts a non-critical but standard functionality.
   • Low (2): The task impacts a minor functionality or a small aspect of the user interface.
   • Minimal (1): The task’s impact is negligible or trivial, with no noticeable effect on functionality or the user experience.
2. Exploitability : The ease with which a vulnerability can be exploited by an attacker.
   • Very High (5): The vulnerability is very easily exploited, potentially requiring no special skills or authentication. Automated exploit tools may be widely available.
   • High (4): The vulnerability is easily exploited, but may require basic technical skills or specific, repeatable conditions.
   • Medium (3): Exploitation requires moderate effort or specific circumstances, such as user interaction or a non-default system configuration.
   • Low (2): Exploiting the vulnerability is difficult, requiring advanced technical skills, privileged access, or overcoming significant mitigating factors.
   • Very Low (1): Exploitation is exceptionally difficult or purely theoretical, requiring conditions that are nearly impossible to achieve in a real-world scenario.
3. Affected Users : The scope or number of users impacted by an issue.
   • All Users (5): The issue affects the entire user base.
   • Majority of Users (4): The issue affects a large portion or majority of users.
   • A Group of Users (3): The issue affects a specific group or a noticeable number of users.
   • Small Number of Users (2): The issue affects a limited number of users, possibly in an edge-case scenario.
   • A Single User (1): The issue is isolated to a single user or account.

You can access this calculator at https://blog.bioaffix.com/tools/bioaffix-priority-severity-calculator/ and use it in your projects free of charge.

In the Scrum methodology, the accurate determination of priority and severity levels for tasks and bugs is vital for project success. Within its own projects, BioAffix utilizes the BioAffix Priority & Severity Calculator, a tool it developed to standardize this process and ensure objective evaluation. This tool enhances consistency and efficiency, thereby contributing to the timely delivery of high-quality software products.