Information Communication Technology (ICT) has become an essential component in healthcare because it enhances interoperability amongst healthcare practitioners by facilitating the seamless and meaningful exchange of information within and across diverse healthcare institutions at the point of care. Consequently, healthcare providers have timely access to patients' information which enables them to manage patients' health in a timely manner. However, interoperability amongst electronic healthcare systems is still a challenge. One of the major obstacles to interoperability of electronic health systems is the problem of usability. Specifically, the ability of healthcare providers to accept and use electronic healthcare systems for information exchange successfully depends on how well the user interface of the electronic healthcare systems have been designed. Thus, a poorly designed user interface, missing critical functionalities in the electronic healthcare system or an inadequate match between the features of the user interface and the user tasks contributes to medical errors, decreased user performance and satisfaction as well as inefficient healthcare such as missing information important to diagnoses. Consequently, healthcare practitioners find it difficult to accept and use electronic healthcare system for patients' care and meaningful information exchange. Hence, this paper appraises the impacts of usability on the interoperability of electronic healthcare systems. The paper also examines the ways of ensuing usability amongst interoperating electronic healthcare systems.

Information and Communication Technologies (ICTs) play significant roles in the improvement of patient care and the reduction of healthcare cost by facilitating the seamless exchange of vital information among healthcare providers. Thus, clinicians can have easy access to patients' information in a timely manner, medical errors are reduced, and health related records are easily integrated. However, as beneficial as data interoperability is to healthcare, at present, it is largely an unreached goal. This is chiefly because electronic Health Information Systems used within the healthcare organizations have been developed independently with diverse and heterogeneous ICT tools, methods, processes and procedures which result in a large number of heterogeneous and distributed proprietary models for representing and recording patients' information. Consequently, the seamless, effective and meaningful exchange of patients' information is yet to be achieved across healthcare systems. This paper therefore appraises the concepts of interoperability in the context of healthcare, its benefits and its attendant challenges. The paper suggests that the adoption of a standardized healthcare terminology, education strategy, design of useable interfaces for ICT tools, privacy and security issues as well as the connection of legacy systems to the health network are ways of achieving complete interoperability of electronic based Health Information Systems in healthcare.