*4.4.1 Stress test*

**4.3 Front-end**

**Figure 3.**

*(right).*

discretion.

lected.

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*4.3.1 User interface (UI)*

*4.3.2 User experience (UX)*

In keeping with the mHealth pipeline discussed previously, the User Interface

*Menu from the "My CF Info" section (left) and list of saved clinical appointments in "My Clinic Appointments"*

A meeting was held with CF nurse specialists and physiotherapists to discuss the plausibility of an Adaptive UI. From this meeting it was determined that a UI model was not required. It was considered that perhaps an Adaptive Navigation model may be beneficial for the use cases as described in 6.5.1 under Preparation; however, this was later dismissed as data recorded and shown in the app is at the patient's

Informal discussions between the CF nurse specialists and the CF adults attending clinic found that this cohort would prefer the UI to be designed so that it does not appear to be a mHealth app. As such, the icon that was to appear on the main screen of the user's smartphone does not contain any indications that the app is for CF; hence this icon is named "My Passport". Furthermore, the style and UI elements in the app were designed so that they do not appear to be "medical" or "clinical". Similarly, all menus and buttons were created to reflect the data col-

On reviewing diabetic patient passports, a number of issues which could prevent the use of such of an intervention was found. Of interest to the UX aspects of this mHealth app is outlining how the app should be implemented into the current care system. A solution for this is discussed in Section 3.2. It is agreed by CF nurse

(UI) and User Experience (UX) of the app are discussed.

*Cystic Fibrosis - Heterogeneity and Personalized Treatment*

The purpose of this test was to evaluate the performance of this app and its design. Seven participants without CF were enlisted who all owned Android devices. The decision to recruit non-CF participants was intended to identify performance and design issues and to remedy them. For the stress test, participants from a similar age range to the target CF adult cohort were chosen. Five participants (three females and two males) between 19 and 51 were recruited. The technical capability of this participants varied, some participants were novices at using technology, while others were ICT professionals.

The participants were asked to download the mHealth passport onto their smartphones and test for 3 months. During this time participants were required to enter, edit, and delete data to "My CF Information" and "My Medical History" a minimum of once a month. However, they were requested perform the same tasks in the "My Clinic Appointments" more frequently (once a week). Each month the participants sent a report of any issues they encountered using the app (such as performance, usability, or general feedback) via email.

At the end of this stress test it was found that there were no major performance issues and the users did not find the mHealth passport difficult to use. The primary issue reported on was a style issue that occurred on different phone screen resolutions whereby the submit button to enter data would remain behind the keyboard (users must close the keyboard before being able to submit). Another issue reported was the lack of clarity or structure when entering dates into the mHealth app. The final issue reported on was that the default "Go" button on the smartphone keyboard did not move to the next text field as expected. Following this feedback, the styling was adjusted and retested on different devices to ensure the submit button was no longer hidden, a calendar was implemented to enter in the date, and finally functionality was created and bound to the "Go" button to ensure users could navigate through the form items. The above solutions were implemented in preparation for pilot testing with CF adult patients.
