Agile (software) developers frequently employ user stories to specify and document user requirements. Is this approach and this documentation compliant with regulatory requirements such as FDA’s software validation guidance respectively IEC 62304 and IEC 62366?
Manufacturers employ user stories to express (software) requirements in a natural language that is understandable to users and customers. Typically, they use phrasing patterns such as:
“As a <role> I can <activity> so that <business value>.”
As an EPAT (extracorporeal pulse activation technology) technician I can adjust the energy level delivered in increments so as to deliver higher or lower energy pulses to the patient’s treatment area.
Regulations such as ISO 13485, IEC 62366 and FDA don’t specify any particular method and thereby also no user stories. However, they mandate that manufacturers explicitly document
User stories mix these aspects; so do the manufacturer confuse the content of the corresponding documents.
The example above reflects a user requirement. Following the phrasing pattern for user requirements the sentence would be: “The user has to be able to select the energy level from the system.”
The part “as to deliver..” expresses the goal – the business value. The goal, however, should be specified either as user need or even as aspect of the intended use description.
The "in increments" is already an aspect of the system requirements specification.
Please consider the following challenges when working with user stories:
Use scenarios (sometimes also referred to as usage scenarios) describe the sequence of user action and system reaction. They can be derived from a stakeholder and task analysis.
You cannot derive use scenarios systematically from user stories (nor vice versa). Neither user stories are a replacement for use scenarios. IEC 62366 explicitly requires manufacturers to identify and evaluate use scenarios for safety relevance.
User stories frequently cause more problems than benefit. We recommend that you rather:
Any questions left? Not quite sure whether your documents meet regulatory requirements? The team of the Johner Institute is looking forward to helping you to compile your technical documents and to fast and safely pass submissions.