Wolfgang Maehr

This is an essay I wrote for a course in user centered design. It can also be downloaded as PDF here. Comments are welcome!

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Since the term User-centred Design (UCD) is rather vague and only described by guidelines, [Gulliksen et al., 2003] this question is a matter of personal taste. Different authors claim different things. Gulliksen et al. [2003] cite different sources ([Nielsen, 1993], [Gould et al. 1997], [ISO 13407, 1999]) in their paper about key principles for UCD that one of the principles is “Active user involvement”:
“[...] representative users should actively participate, early and continuously throughout the entire development process and throughout the system life-cycle. The users should be directly involved, both in the development project and in related activities, such as, organisational development and designing new work practices [...]“

In contrast, Iivari [2004] writes about Participatory Design (PD) in respect to UCD and Usability Engineering (UE):
“However, there is confusion related to the terms. The terms of UE and UCD are often used interchangeably. (Kujala 2003.) In addition, PD has been defined to denote everything that somehow involves users in the development (Spinuzzi 1996). Also the term user involvement seems to denote a variety of approaches that emphasize one way or another ‘direct contact with users’ ranging from active user participation in the design process to the involvement of users as mere providers of information and objects of observation. (Bannon 1991, Kujala 2003, Mumford 1983.) [...]“

These two positions can – but do not need to be – seen opposing each other; they are not totally exclusive. In its initial idea [Spinuzzi, 1996] of users as designers, PD is not outside of the key principles defined by Gulliksen [2003]. However, is Gulliksen rather vague with the term “actively”. This could either mean that the user becomes a designer (like in PD), or – the way I interpret it – is actively integrated in the development process by user testing, evaluation of prototypes or hosting of usage-context visits. Still, the interesting question is not if PD is a part of UCD or not, but what kind of different challenges both approaches face. For this reason the rest of this essay will focus on two representative problems.

The central issue of both methods is the representation of a user. This representation should be as accurate as possibility to guarantee a validity of the results. For the Participatory Design the main validity problems are finding representative users for the stakeholders and to keep them representative. The first task can be solved by increasing resources spent on the search and thorough examination of the representative; the second problem is harder to tackle. To keep the users fresh and unbiased, Gulliksen et al. [2003] propose to use them only temporarily and replace them after a while. Otherwise, the users grow to domain experts and may loose touch with then normal users. This, however, bears the problem that these users lack the needed terminology and lose time for introduction to the domain to be able to communicate more differentiated issues [cp. Luck, 2003]. The UCD process has here a slight advantage, since it uses a usability expert to mostly interact with the user [cp. Gulliksen et al., 2003]. This expert can take the role of a mediator and translate between both sides (users and developers). In order to make this translation process work, the usability expert however has to devote enough time with the user to maintain credibility [Mankin et al., 1997]. Since the usability expert is endangered to be overloaded with (development) tasks like design and evaluation (even for multiple projects), he/she is also endangered loose this crucial touch with the real users. Therefore the usability expert also needs periodic meetings with the users.

A second set of problems is the coverage of all stakeholders. While UCD mostly focusses upon the user (only scarcely on the context) [cp. Gulliksen et al., 2003], tries PD to include all stakeholders into the design process [cp. Mankin et al., 1997]. The obvious problem of UCD is here that some stakeholders may be neglected and left out in the design process. PD on the other hand has to be careful on not bloating the project groups with too many stakeholders, which renders meetings unproductive. This means that not all decisions can be made by all stakeholders [Mankin et al., 1997], which requires that the appropriate and representative stakeholders have to be found for each decision. This limitation can have a backlash on the stakeholder identification with the finished product since the stakeholders were intended to design all parts of his/her own product; which is not the case if decisions are made by only the relevant stakeholders.

Last, but not least, both methods have problems with generalisation/representativeness and suggested solutions. Regarding the former, Luck [2003] describes the problem of the generalisation of user preference as the difficult balance between extrapolating too much and too little. This again concerns the question if one user preference is representative. A question that only can be answered by a larger number of samples. Regarding the latter, the question of solutions suggested by users is a tricky one since the a rejection of such a solution proposal can be impeding the further work of a user representative. On the other hand these suggestions can limit the solution, in case that the project is too user-oriented.

To conclude one can say that the representativeness is a core issue of both methods and that User-centered Design has advantages when it is about formal results from user involvement. This can be a strength, especially for bigger projects. For small companies and projects the PD might bear better chances, also because the users do then a part of the designers’ work and identify themselves with the product more.

• L. Bannon, 1991. From Human Factors to Human Actors: The Role of Psychology and Human-computer Interaction Studies in System Design, in Greenbaum – Kyng.
• J. D. Gould, S. J. Boies and J. Ukelson, 1997. How to Design Usable Systems, in M. Helander, T. K. Landauer and P. Prabhu (eds.) Handbook of Human-Computer Interaction, Amsterdam: Elsevier Science B.V.
• ISO 13407, 1999. Human-centred design process for interactive systems. Available (2006-04-06): http://www.usabilitynet.org/tools/13407stds.htm
• N. Iivari, 2004. Enculturation of User Involvement in Software Development Organizations—An Interpretive Case Study in the Product Development Context, in Proceedings of NordiCHI 2004, ACM Press, pages 287–296.
• S. Kujala, 2003. User Involvement: A Review of the Benefits and Challenges, in Behaviour & Information Technology, Jan-Feb, Vol. 22, No. 1, pages 1-16.
• E. Mumford, 1983. Designing Human Systems for New Technology: The ETHICS Method, Manchester: Manchester Business School.
• J. Nielsen, 1993. Usability Engineering, Cambridge, MA: AP Professional.
• C. Spinuzzi, 2002. A Scandinavian Challenge, a US Response: Methodological Assumptions in Scandinavian and US Prototyping Approaches, in Proceedings of SIGDOC 2002, pages 208-215.