Assessing the Sustainability-Quality Model: A Multi-Year Empirical Study in Education

Sustainability is increasingly recognised as an essential concern in software engineering, yet practical sound approaches for integrating it into quality assessment remain limited. The Sustainability-Quality (SQ) Model, introduced as part of the Sustainability Assessment Framework (SAF) Toolkit, offers a structured way to connect quality attributes (QAs) with four sustainability dimensions: technical, environmental, economic, and social. To better understand how the model can be applied in practice, this study analyses its use in a multi-year educational setting where master’s students applied the SQ Model in 63 projects across diverse domains such as mobility, healthcare, agriculture, education, and cultural heritage. From these projects, 275 SQ concerns were collected and examined with respect to their frequency and classification accuracy. The analysis shows that concerns such as accessibility, interoperability, and resource utilisation were identified most often, whereas sustainability-specific concerns such as carbon footprint and environmental risk mitigation appeared less frequently. An overall classification accuracy of 88% was achieved, suggesting that the model can be applied reliably even by novices. These findings provide empirical evidence of the SQ Model’s usability, highlight recurring challenges in its application, and point to opportunities for improving sustainability education in software engineering.