Introduction
Modern computer information systems have a proven record in supporting information management tasks in healthcare.1,2 However, clinical information systems lacking usable designs may increase the mental workload imposed on their users and negatively impact on patient safety.3–5 Today, with the nearly universal computerization of general practice in the UK,6 general practitioners (GPs) are faced with the challenge of working with computer systems that could be potentially adding to their cognitive workload.7
GP Systems of Choice (GPSoC) in England (Table 1) do not have to conform to any specified usability requirements, although there have been initiatives to promote usability supported by the National Health Service (NHS), including the Microsoft Health Common User Interface.8 Usability has been defined as ‘the capacity of a system to allow users to carry out their tasks safely, effectively, efficiently and enjoyably’.9 It largely relates to the quality of the information design and system navigability, and has a lot to do with user interfaces.10,11 Usability is a very important aspect in system design12 and may impact user satisfaction, user fatigue, clinical productivity, error rates, and overall patient safety.
Clinical care is a complex and mentally demanding activity. It usually involves multitasking, where communication skills13 are combined with pattern recognition, clinical reasoning and problem solving skills.14 In primary care, the high levels of uncertainty,15 the variety of clinical presentations seen16 and need to deal with vast amounts of information routinely received from other care settings17 add to this complexity. All of these contribute to the mental workload experienced in general practice.18
Mental workload has been defined as the mental effort involved in performing any given task.19 Excessive simultaneous tasks or very demanding individual tasks may cause cognitive overload.20 In healthcare, multitasking may lead to errors.21 Information systems should help users complete tasks with ease. Their user interfaces should be carefully designed to ensure that the way information is displayed does not negatively affect the cognitive workload experienced by healthcare professionals.22 Improved user interfaces should reduce medical errors and improve patient care.23
Scottish GPs have expressed reservations about the usability of their computer systems.24 Usability issues in healthcare have been noted elsewhere. Examples cited are fixed sequences of steps and tasks, poorly supported documentation and retrieval of information,25 problems relating to the efficiency of use, intuitiveness, and poor fit for multiprofessional needs,26 and poor integration into workflow.27 In healthcare information technology, the main challenge today appears to lie on the design of convenient, efficient and acceptable interfaces.28 Failure of many clinical information systems has been attributed to the lack of human-centered design approaches.29,30 Problems with usability have been linked to patient safety elsewhere.31–33 In the UK, poor usability has also been identified as a safety issue.34,35
Guidelines for the evaluation of the usability of electronic record systems in primary care exist.36 Among several existing validated subjective mental workload tools,37 NASA-TLX38 has been commonly used in health care. This is a multidimensional scale consisting of two parts: 1) six 20-point visual analogue sub-scales that measure contributing factors to the overall cognitive load (measures of workload): mental demand, physical demand, temporal demand, performance, effort and frustration; and 2) a set of pairings combining the different factors to be rated according to relevance, in order to weight the subjective importance given to the difference factors (sources of workload). This has been used in a variety of health information and communication technology evaluations such as nursing intensive care,39 anesthetic work,19 surgical training and surgery,40,41 and electronic white boards.42
This study looks to identify where potential usability issues with current existing GP systems in the NHS in England may exist, by exploring the subjective cognitive workload experienced by GPs when they carry out common clinical tasks with their computer systems. The study hopes to raise awareness of the influence of usability on safety among system users, developers and policy makers.