ABSTRACT
Anxiety disorders are among the most common psychiatric problems in youth, fail to spontaneously remit, and place some youth at risk for additional behavioral and emotional difficulties. Efforts to target anxiety have resulted in evidence-based interventions but the resulting prevention effects are relatively small, often weakening over time. Mobile health (mHealth) tools could be of use to strengthen the effects of anxiety prevention efforts. Although a large number of mHealth apps have been developed, few have been evaluated in terms of usability prior to clinical effectiveness testing. Because usability is one of the main barriers to mHealth usage and adoption, the objective of this research was to evaluate the usability of a smartphone application (app) corresponding to an indicated prevention and early intervention targeting youth anxiety. To accomplish this, 132 children (M age = 9.65; 63% girls) and 45 service providers (M age = 29.13, 87% female) rated our app along five established dimensions of usability (ease of use, ease of learning, quality of support information, satisfaction, and stigma) using a standardized group-based testing protocol. Findings showed that the app was highly and positively rated by both youth and providers, with some variations (lower ratings when errors occurred). Path analyses findings also showed that system understanding was significantly related to greater system satisfaction, but that such relation occurred through the quality of support information offered by the app.
ABSTRACT
The introduction of software technology in a life-dependent environment requires the development team to execute a process that ensures a high level of software reliability and correctness. Despite their popularity, agile methods are generally assumed to be inappropriate as a process family in these environments due to their lack of emphasis on documentation, traceability, and other formal techniques. Agile methods, notably Scrum, favor empirical process control, or small constant adjustments in a tight feedback loop. This paper challenges the assumption that agile methods are inappropriate for safety-critical software development. Agile methods are flexible enough to encourage the rightamount of ceremony; therefore if safety-critical systems require greater emphasis on activities like formal specification and requirements management, then an agile process will include these as necessary activities. Furthermore, agile methods focus more on continuous process management and code-level quality than classic software engineering process models. We present our experiences on the image-guided surgical toolkit (IGSTK) project as a backdrop. IGSTK is an open source software project employing agile practices since 2004. We started with the assumption that a lighter process is better, focused on evolving code, and only adding process elements as the need arose. IGSTK has been adopted by teaching hospitals and research labs, and used for clinical trials. Agile methods have matured since the academic community suggested they are not suitable for safety-critical systems almost a decade ago, we present our experiences as a case study for renewing the discussion.
ABSTRACT
This paper presents an overview of the image-guided surgery toolkit (IGSTK). IGSTK is an open source C++ software library that provides the basic components needed to develop image-guided surgery applications. It is intended for fast prototyping and development of image-guided surgery applications. The toolkit was developed through a collaboration between academic and industry partners. Because IGSTK was designed for safety-critical applications, the development team has adopted lightweight software processes that emphasizes safety and robustness while, at the same time, supporting geographically separated developers. A software process that is philosophically similar to agile software methods was adopted emphasizing iterative, incremental, and test-driven development principles. The guiding principle in the architecture design of IGSTK is patient safety. The IGSTK team implemented a component-based architecture and used state machine software design methodologies to improve the reliability and safety of the components. Every IGSTK component has a well-defined set of features that are governed by state machines. The state machine ensures that the component is always in a valid state and that all state transitions are valid and meaningful. Realizing that the continued success and viability of an open source toolkit depends on a strong user community, the IGSTK team is following several key strategies to build an active user community. These include maintaining a users and developers' mailing list, providing documentation (application programming interface reference document and book), presenting demonstration applications, and delivering tutorial sessions at relevant scientific conferences.
