172 2005 IRMA International Conference Copyright © 2005, Idea Group Inc. Copying or distributing in print or electronic forms without written permission of Idea Group Inc. is prohibited. User Acceptance of Technology and Success in IS Implementation Eivind Brevik The Norwegian School of Infor. Technology, Schweigaardsgate 14, PO Box 111, N-1319 Bekkestua, Norway, eivind.brevik@nith.no ABSTRACT To achieve business effects from IT investments it is important to understand the forces of user acceptance. This paper evaluates how useful the Unified Theory of Acceptance and Use of Technology (UTAUT) is to explain success within information system implemen- tation. The research has been done by investigating the user acceptance as success measure within the major IS implementation research streams, then comparing these success measures with the constructs of the UTAUT. The findings of this paper are that the UTAUT is useful in explaining the success measures of the different streams in terms of user acceptance, but not the interaction between the measures in a process view. Thus, it fails partly in explaining all success dimensions of IS implementation. INTRODUCTION A recent article in MIS Quarterly Executive by Luftman and McLean (2004) states the top five key issues for IT executives. They are as follows: 1) IT and business alignment, 2) IT strategic planning, 3) Security and privacy, 4) Attracting, developing, and retaining IT professionals, and 5) Measuring the value of IT investments. Except for number 3) and 4), the key issues concern how technology is used in organisations. Use of technology to support business processes, enables competitive advantage and creating value is highly relevant for most businesses today. How to understand these forces are therefore impor- tant research questions that should be interesting for practitioners as well as researchers. One way to understand these forces is by researching user acceptance of technology. The research on individual acceptance of technology is a mature area within IS research (Venkatesh, Morris, Davis and Davis, 2003), and several theoretical models have been developed. In a recent paper by Venkatesh, Morris, Davis and Davis (2003) there is a proposal of a Unified Theory of Acceptance and Use of Technology (UTAUT). This theory builds upon eight different models within technology acceptance and innovation diffusion. An information system (IS) not being used is most likely not a success. However, depending on the dimension investigated a system may be evaluated as a success even though it is not used. If evaluated solely in terms of technical functionality the system may well be a success, but still rejected by the intended users. Thus, implementation of the IS in the organisation is an important part of the utilisation of technology. Within research on IS implementation success there are different research streams focusing on different aspects on what influences successful implementation. Can knowledge about user acceptance im- prove the success of IS implementation? There is a considerable research body on user acceptance of technology and IS implementation research (see respectively Venkatesh et al. 2003 and Larsen 2001, Kwon and Zmud 1987 for an overview). However, there is a lack of research studying the usefulness of the UTAUT in explaining success within IS implementation research. Thus, it is interesting to investigate how user acceptance models like the UTAUT, can explain and predict success within the different streams of IS implementation research. This paper will discuss critically to what extent the UTAUT is useful in explaining success within the different streams of IS implementation research. The paper will be structured as follows. Section 2 will briefly present the UTAUT. Section 3 presents and discusses user acceptance within the IS implementation research streams, and then conducts a comparative analysis between the UTAUT and the success measures within the different research streams of IS implementation. Conclusions and recommendations are found in section 4. A UNIFIED THEORY, THE UTAUT The UTAUT builds upon eight different models within technology acceptance and innovation diffusion. These are: • Theory of reasoned action (TRA), (Fishbein and Ajzen, 1975), • Technology acceptance model (TAM), (Davis,1989), • Motivational model (MM), (Davis, Bagozzi and Warshaw, 1992), • Theory of planned behaviour (TPB), (Ajzen 1991), • Combined TAM and TPB (C-TAM-TPB), (Taylor and Todd 1995), • Model of PC utilization (MPCU), (Thompson, Higgins and Howell, 1991), • Innovation Diffusion Theory (IDT/DOI), (Moore and Benbasat, 1991) adapted the characteristics presented by Rogers (1983), and • Social Cognitive Theory (SCT) (Compeau and Higgins, 1995, 1999). The different theories have used different constructs for what can seem to be the same phenomenon. According to Venkatesh et al. (2003) this undermines the possibility of different research streams to combine results and findings, and ultimately sub-optimize research. To bring forth a possibility to unify the different theories, Venkatesh et al. have developed a unified theory and also tested it empirically. This theory adapts several of the constructs from the above described models and theories. Some of the constructs are believed to represent the same phenomenon, and thus combined to a new or single construct. UTAUT have four determinants of behavioural intention and actual use; perfor- mance expectancy, effort expectancy, social influence and facilitating conditions, see Figure 1. Performance expectancy explains the degree in which an individual believes that using the system will help attain gains in job performance, Effort expectancy, the degree of ease in using of the system, Social influence , the degree in which an individual relies upon reference persons’ beliefs in using the system, and Facilitating conditions, the degree in which an individual believes that organisational and technical infrastructure support system use. The UTAUT has been empirically tested and resulted in explaining 70 % of the variance in expectations (Venkatesh et al. 2003). This is a much higher explanatory power than found by any of the eight models used as foundation for the UTAUT. The critique of the basic assumptions underlying the user acceptance models that the UTAUT is based on questions the usefulness of the model in explaining IS success (see for instance O’Keefe, 2002). The insuffi- cient considerations of cognitive issues described within cognitive dissonance (Festinger, 1957) as well as Expectation-Disconfirmation Theory (Bhattacherjee and Premkumar, 2004) reduce the usefulness of 701 E. Chocolate Avenue, Suite 200, Hershey PA 17033, USA Tel: 717/533-8845; Fax 717/533-8661; URL-http://www.idea-group.com ITP5157 IDEA GROUP PUBLISHING This paper appears in Managing Modern Organizations Through Information Technology, Proceedings of the 2005 Information Resources Management Association International Conference, edited by Mehdi Khosrow-Pour. Copyright 2005, Idea Group Inc.