The debt quality model is inspired on SQALE method.

According to the definition in its website:

The SQALE method has been developed to answer a generic and permanent need for assessing the quality of source code. Standards like ISO 9126 and ISO/IEC 15939 do not provide effective support for this challenge. The SQALE method is targeted for an automated implementation. It is generic and language and tool independent. 

The SQALE method is particularly devoted to the management of the Technical Debt (or Design Debt) of software developments. It allows:

Although SQALE method is focused on source code, we have adapted it on our way to be able to focus on JIRA issues, instead of lines of code.