## 5 Methodology  
This section describes the process that was followed to create the assessment tool with heuristics and guidelines for urban interfaces. It also provides details of the field study that was conducted in order to see the proposed guidelines 'in action' and explains how the field study for evaluating different urban interfaces was planned and conducted, how field study data was gathered, and how data was then analyzed.  
1. _Defining usability guidelines exclusively for urban interfaces._ In this step a series of 14 specific guidelines were defined that are based on the literature review mentioned above. The specific features of urban interfaces were also taken into account, including physical location, use schedule, and type of person or citizen using them, amongst others.
2. _Selecting the urban interfaces that will be evaluated._ A total of eight interfaces were selected--from government and private organizations--each serving different purposes and situated in different physical locations. The interfaces are located in the following cities: Mexico City and Monterrey in Mexico, and Cali and Bogota in Colombia.
3. _Field study planning._ For this, the assessors performed an initial cognitive walkthrough [49] for each of the interfaces selected. Following this, research materials such as screeners, observation guidelines and note-taking methods were designed for the researcher [50].
4. _Performing a field study of each interface._ To be able to revise the guidelines in action, a field study was conducted with users that involved qualitative research based on observations [24; 36] of different types of users. This qualitative research involved observing individuals, as shown in Figure 1, as they used the eight interfaces selected. During each observation researchers formally documented how each of the 14 guidelines influenced the experience of each user.
5. _Gathering and analyzing results on the use of each interface._ To evaluate user experiences both qualitative and quantitative data were collected. Regarding the qualitative data that was collected, researchers documented the following: the aspects of the urban interface that had a negative impact, those that had a positive impact or rating, and any comments offered by the users themselves. Next, the data were recorded in _Reframer_, a specialized cloud-based tool for logging field study notes and observations. Once notes are logged, the tool then allows users to analyze their notes to detect patterns and reoccurring themes ([[https://www.optimalworkshop.com/reframer](https://www.optimalworkshop.com/reframer)]([https://www.optimalworkshop.com/reframer](https://www.optimalworkshop.com/reframer))) [51]. In addition, a customer experience map [52], as shown in Figure 2, was used in order to map the emotional journey of the user experience in each touchpoint or moment that a person has contact with an interface. This visual map helps to better understand where the experience was better or worse and to understand which guidelines were followed and which were not.  
Regarding the quantitative data, researchers also documented the time taken to complete tasks; at a later stage, this information could be used to determine the cognitive load [53] for each of the interfaces.  
All the information gathered both quantitatively and qualitatively following the application of the guidelines in this field study are analyzed to determine the effectiveness of the proposed guidelines to discover problems common to the user experience of the interfaces evaluated.