This research study explores how the nature and type of usability failures impact task performance in a healthcare organization. Healthcare organizations are composed of heterogeneous and disparate information systems intertwined with complex business processes that create many challenges for the users of the system. The manner in which Information Technology systems and products are implemented along with the overlapping intricate tasks the users have pose problems in the area of usability. Usability research primarily focuses on the user interface; therefore, designing a better interface often leaves security in question. When usability failures arise from the incongruence between healthcare task and the technology used in healthcare organizations, the security of information is jeopardized. Hence, the research problem is to understand the nature and types of usability-related security failures and how they can be reduced in a Healthcare Information System. This research used a positivist single case study design with embedded units, to understand the nature and type of usability-related information systems security failures in a Healthcare context. The nature and types of usability failures were identified following a four-step data analysis process that used terms that defined (1) user failures in a large healthcare organization, (2) Task Technology Fit theory, (3) the Confidentiality Integrity and Availability triad of information protection that captured usability-related information system security failures, and (4) by conducting semi-structured interviews with users of the Healthcare Information System capturing and recording their interactions with the usability failure. The captured reported usability-related information system security failures dated back five years within a healthcare organization consisting of a network of 128 medical centers. The evaluation of five years of data and over 8,000 problems reported by healthcare workers allowed this research to identify the misalignment of healthcare task to the technology used, and how the misalignment impacted both information security and user performance. The nature of usability failures were centered on technical controls, however, the cause of the failures was predominately information integrity failures and the unavailability of applications and systems. Usability-related information system security failures are primarily not recognized due to the nature of healthcare task along with the methods healthcare workers use to mitigate such failures by employing workarounds to complete a task. Applying non-technical security controls within the development process provides the clearest path to addressing throughout the organization the captured usability-related information system security failures.

Dans cette thèse, nous questionnons l’impact du terrorisme international et des mesures de sûreté sur le comportement des usagers du réseau de transport aérien mondial. A l’aide d’un modèle économétrique, nous analysons une base de données inédite, AirNetTerror, composée de l’ensemble des vols internationaux à destination des Etats-Unis de 1990 à 2006, et des données du terrorisme international par pays sur cette période. La pertinence de notre travail est double. D’une part, nos interrogations sur les comportements des voyageurs et leurs éventuelles substitutions d’itinéraires en lien avec le terrorisme international n’ont, à notre connaissance, jamais été traitées. D’autre part, en abordant le transport aérien sous l’angle du réseau, nous proposons une vision dynamique des répercussions des comportements des usagers en lien avec la menace terroriste et les mesures de sûreté. En particulier, la prise en compte de la situation de sûreté interdépendante régissant le réseau aérien mondial nous permet de questionner l’existence de failles dans les mesures de sûreté. Nos résultats soulignent l’impact avéré et significatif des événements du terrorisme international, mais aussi des mesures de sûreté sur le réseau de transport aérien mondial. De plus, nous observons localement des substitutions d’itinéraires des voyageurs aériens en lien avec ces phénomènes. Ainsi, l’effet combiné de la menace terroriste internationale et des mesures de sûreté semble être à l’origine de ruptures d’équilibre, certes limitées mais réelles, des flux de passagers du réseau de transport aérien mondial. Notre thèse, parce qu’elle place le comportement du voyageur au centre des interactions stratégiques entre les acteurs de la sûreté et les terroristes, permet d’apporter une vision inédite de l’impact du terrorisme international sur le transport aérien. / In our dissertation, we question the impact of both international terrorism and security measures on the behavior of the users of the global air transportation network. Using an econometric model, we analyze a new database, AirNetTerror, which contains data on all international passenger flows toward the U.S. from 1990 to 2006 as well as the events of international terrorism by country for the same period. The relevance of our research is twofold. On the one hand, our investigation regarding air travelers’ behavior and their possibilities of modifying their itinerary in light of international terrorism has – so far as we know – never been studied. On the other hand, as we analyze passenger flows from the perspective of the network, we propose a dynamic representation of the impact of travelers’ behavior changes related to terrorist threats and security measures. In particular, taking into account the interdependent security that rules the global air transport network, allows us to question the existence of failures in security measures. Our results underline a significant impact of both international terrorist events and security measures. Furthermore, we locally observe itinerary modifications of travelers that are linked to the previous phenomena. Thus, the combined effect of terrorist threats and security measures seems to lead to equilibrium breaks – that are limited but real – in passenger flows of the global air network. Our thesis offers a different representation of the impact of international terrorism on air transport by placing the traveler’s behavior at the center of the strategic interactions between security actors and terrorists.