Cognitive walkthrough

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The Cognitive Walkthrough method is a usability inspection method used to identify usability issues in a piece of software or web site, focusing on how easy it is for new users to accomplish tasks with the system. The method is rooted in the notion that users typically prefer to learn a system by using it to accomplish tasks, rather than, for example, studying a manual. The method is prized for its ability to generate results quickly with low cost, especially when compared to usability testing, as well as the ability to apply the method early in the design phases, before coding has even begun.

A cognitive walkthrough starts with a task analysis that specifies the sequence of steps or actions required by a user to accomplish a task, and the system responses to those actions. The designers and developers of the software then walkthrough the steps as a group, asking themselves a set of questions at each step. Data is gathered during the walkthrough, and afterwards a report of potential issues is compiled. Finally the software is redesigned to address the issues identified.

The method was developed in the early nineties by Wharton, et al, and reached a large usability audience when it was published as a chapter in Jakob Nielsen's seminal book on usability, "Usability Inspection Methods." The Wharton, et al method required asking four questions at each step, along with extensive documentation of the analysis. In 2000 there was a resurgence in interest in the method in response to a CHI paper by Spencer who described modifications to the method to make it effective in a real software development setting. Spencer's streamlined method required asking only two questions at each step, and involved creating less documentation. Spencer's paper followed the example set by Rowley, et al who described the modifications to the method that they made based on their experience applying the methods in their 1992 CHI paper "The Cognitive Jogthrough".

The effectiveness of methods such as cognitive walkthroughs is hard to measure in applied settings, as there is very limited opportunity for controlled experiments while developing software. Typically measurements involve comparing the number of usability problems found by applying different methods. However, Gray & Salzman called into question the validity of those studies their dramatic 1998 paper "Damaged Merchandise", demonstrating how very difficult it is to measure the effectiveness of usability inspection method. However, the consensus in the usability community is that the congnitive walkthrough method works well in a variety of settings and applications.

[edit] Further reading

• Wharton, Cathleen, et. al. (1994). The Cognitive Walkthrough Method: A Practictioner's Guide. In Nielsen, Jakob, and Mack, R. (eds) Usability Inspection Methods. Chichester: John Wiley and Sons. ISBN 0-471-01877-5
• Spencer, R. (2000) The Streamlined Cognitive Walkthrough Method, Working Around Social Constraints Encountered in a Software Development Company CHI 2000 vol.2 issue 1 pp353-359
• Rowley, David E., and Rhoades, David G (1992). The Cognitive Jogthrough: A Fast-Paced User Interface Evaluation Procedure. Proceedings of CHI '92, 389-395.
• Gray, W. & Salzman, M. (1998). Damaged merchandise? A review of experiments that compare usability evaluation methods, Human-Computer Interaction 13, 203-61.
• Blackmon, M. H. Polson, P.G. Muneo, K & Lewis, C. (2002) Cognitive Walkthrough for the Web CHI 2002 vol.4 No.1 pp463-470
• Blackmon, M. H. Polson, Kitajima, M. (2003) Repairing Usability Problems Identified by the Cognitive Walkthrough for the Web CHI 2003 pp497-504
• Dix, A., Finlay, J., Abowd, G., D., & Beale, R. (2004). Human-computer interaction (3rd ed.). Harlow, England: Pearson Education Limited. p321
• Gabrielli, S. Mirabella, V. Kimani, S. Catarci, T. (2005) Supporting Cognitive Walkthrough with Video Data: A Mobile Learning Evaluation Study Mobile HCI ’05 pp77-82
• Good, N. S. & Krekelberg, A. (2003) Usability and Privacy: a study of KaZaA P2P file-sharing CHI 2003 Vol.5 no.1 pp137-144
• Gray, W.D. & Salzman, M.C. (1998) Damaged Merchandise? A Review of Experiments that Compare Usability Evaluation Methods Human-Computer Interaction, Vol.13 No.3 pp203-261
• Gray, W.D. & Salzman, M.C. (1998) Repairing Damaged Merchandise: A rejoinder. Human-Computer Interaction vol.13 no.3 pp325-335
• Hornbaek, K. & Frokjaer, E. (2005) Comparing Usability Problems and Redesign Proposal as Input to Practical Systems Development CHI 2005 391-400
• Jeffries, R. Miller, J. R. Wharton, C. Uyeda, K. M. (1991) User Interface Evaluation in the Real World: A comparison of Four Techniques Conference on Human Factors in Computing Systems pp 119 – 124
• Lewis, L. Polson, P, Wharton, C. & Rieman, J. (1990) Testing a Walkthrough Methodology for Theory-Based Design of Walk-Up-and-Use Interfaces Chi ’90 Proceedings pp235-242
• Rowley, D. E. & Rhoades, D. G. (1992) The Cognitive Jogthrough: A Fast-Paced User Interface Evaluation Procedure CHI ’92 pp389-395
• Sears, A. (1998) The Effect of Task Description Detail on Evaluator Performance with Cognitive Walkthroughs CHI 1998 pp259-260
• Wharton, C. Bradford, J. Jeffries, J. Franzke, M. Applying Cognitive Walkthroughs to more Complex User Interfaces: Experiences, Issues and Recommendations CHI ’92 pp381-388