Page - 50 - in Applied Interdisciplinary Theory in Health Informatics - Knowledge Base for Practitioners

1. Introduction to User Centered Design and Activity Theory as a Human Computer Interaction Framework In recent years, there has been a huge increase in the development of mHealth interventions to improve healthcare delivery and services. The ubiquity of mobile devices allows for the provision of mHealth interventions, which affords several benefits including patient autonomy through self-management, cost saving and an increase in health literacy [2, 3]. To optimise both the effectiveness and usefulness of these mobile interventions, usability and acceptance are paramount. Involving end users in the technology lifecycle process could help to ensure that end users’ needs, and expectations are met, as well as increasing the likelihood of acceptance and adoption for optimum clinical impact where relevant [4]. This section explores the origins of User Centred Design (UCD) and Activity Theory (AT), and explains the usefulness of their application in terms of understanding the complexities of users and their interactions in system design. 1.1. An overview of Human Computer Interaction While there has been a significant development in mHealth self-management interventions, these are sometimes lacking in theoretical underpinnings and adequate assessment of end-user needs [5,6], which then restricts their effectiveness. Human Computer Interaction [HCI] is an interdisciplinary field concerned with the design, implementation and evaluation of interactive systems [7]. Its methodologies and theories are drawn from multiple fields including computer science; sociology; psychology; ergonomics; anthropology and cognitive science, however its roots fundamentally lie in the social sciences, specifically cognitive theory and human factors [8]. The theoretical underpinnings of HCI contribute to the understanding of aspects of design specifically relating to perception; cognition; behaviour and interaction. A selection of some of the theories and models used within HCI include: Perception (Psychology) ● Hick’s Law: states the time it takes to make a decision increases as the number of alternatives increase [9]. ● Fitts’ Law: predicts that the time required to rapidly move to a target area is a function of the ratio between the distance to the target and the width of the target [10]. Cognition & Behaviour (Sociology) ● Action Theory: Norman’s seven stages of action models the way people act when they are interacting in the world to achieve their goals [11]. ● Activity Theory: a theoretical framework for analysing human practices as developmental processes with both individual and social levels interlinked at the same time [12]. Interaction (Unique to HCI) ● GOMS: models tasks and user actions; set of Goals, Operators and Methods for achieving goals, and a set of Selection rules for choosing methods for goals used [13]. ● KLM: predicts how long it takes a user to complete a task. Based on GOMS, it provides an analysis of steps taken [14]. A.GoodandO.Omisade /LinkingActivityTheorywithUserCentredDesign50