Development & psychometrics of the SOLI...

Software security is a crucial requirement for most of the software used nowadays. Besides specialized knowledge of engineers and developers, organizational culture can contribute to software security to a great extent if specific cultural dimensions are in alignment with security. The purpose of this study is to develop and evaluate the SOLID-S, a six-dimensional inventory assessing this type of software security culture in software development companies. We present the iterative test development process of the inventory and examine its psychometric properties in an empirical study with N=327 participants by means of Item Response Theory. We identify the SOLID-S to have appropriate measurement qualities in terms of accuracy, fairness across subgroups, item fit and dimensionality. Results suggest that the inventory's subscales comply with the Partial Credit Model and, hence, raw sum scores of the subscales can be interpreted reliably. The SOLID-S can therefore be used for research, as a starting point for organizational change programs, or to evaluate the effectiveness of interventions aiming to improve security culture.