Factors Influencing Usability of a Smartphone App to Reduce Excessive Alcohol Consumption: Think Aloud and Interview Studies

Abstract

Background: Interventions delivered by smartphone apps have the potential to help drinkers reduce their consumption of alcohol. To optimize engagement and reduce the high rates of attrition associated with the use of digital interventions, it is necessary to ensure that an app's design and functionality is appropriate for its intended purposes and target population.

Aims: To understand the usability of an app to help people reduce their alcohol consumption.

Method: The app, Drink Less, contains a core module focusing on goal setting, supplemented by five additional modules: self-monitoring and feedback, identity change, cognitive bias re-training, action planning, and social comparison. Two studies were conducted, a "think aloud" study performed with people using the app for the first time and a semistructured interview study performed after users had had access to the app for at least 2 weeks. A thematic analysis of the "think aloud" and interview transcripts was conducted by one coder and verified by a second.

Results: Twenty-four participants, half of whom were women and half from disadvantaged groups, took part in the two studies. Three main themes identified in the data were "Feeling lost and unsure of what to do next," "Make the app easy to use," and "Make the app beneficial and rewarding to use." These themes reflected participants' need for (i) guidance, particularly when first using the app or when entering data; (ii) the data entry process to be simple and the navigation intuitive; (iii) neither the amount of text nor range of options to be overwhelming; (iv) the app to reward them for effort and progress; and (v) it to be clear how the app could help alcohol reduction goals be reached.

Conclusion: First-time and experienced users want an alcohol reduction app to be easy, rewarding, and beneficial to use. An easy-to-use app would reduce user burden, offer ongoing help, and be esthetically pleasing. A rewarding and beneficial app would provide positive reinforcement, give feedback about progress, and demonstrate credibility. Users need help when first using the app, and they need a compelling reason to continue using it.

Keywords: alcohol; app; digital health; interview study; mHealth; qualitative; think aloud.

Figure 1

Normative feedback. (A) Users were asked to indicate how they thought their drinking compared to (1) other people in the UK and (2) other people of their age and gender. (B) Feedback showed how a user’s drinking actually compared to people in the UK and people of their own age and gender. (C) More feedback showed how a user’s drinking compared to people in the UK and people of their own age and gender.

Figure 2

Self-monitoring and feedback: monitoring consumption and the consequences of consumption. (A) Users could select one of six types of drink … (B) … and then chose options for each. (C) Users monitored the consequences of consumption by recording daily their mood, productivity, clarity, and sleep quality scores.

Figure 3

Self-monitoring and feedback: alerts to monitor consumption and consequences of consumption. (A) Prompt on the user’s home screen. (B) Alert on the “badge app icon” (fifth row, last app). (C) Alert on the dashboard (in “Things to do today”).

Figure 4

Self-monitoring and feedback: feedback about consumption and consequences of consumption. (A) Dashboard shows units, calories, and spending graphs as well as summary feedback about progress against goals. (B) The calendar provided an overview of a user’s recorded drinks, with days underlined according to whether a user had drunk or not. (C) Your Hangover and You presented scores from the mood diary (Figure 2C) in graph form.

Figure 5

Self-monitoring and feedback: feedback about consumption. (A) The Last Week screen shows whether a user exceeded, hit, or missed the goal for the previously completed week. (B) The “Hit Rate” screen provided an overview of how many times the goal had been exceeded, hit, or missed since the app was downloaded. (C) The “Success Rate” screen provided a total of how many times the goal had been exceeded, hit, or missed since the app was downloaded.

Figure 6

Action plans—main screen and Why set an action plan. (A) The main Action Plans screen contained information about the benefits of setting an action plan and an example of one. (B) The Create an Action Plan screen asked users to fill in two fields corresponding to the If and Then components of an implementation intention. (C) Information explaining the benefits of an action plan and examples of action plans.

Figure 7

Cognitive bias re-training. (A) Users were instructed to use their finger to push the alcoholic drink away from them and to pull the non-alcoholic drink toward them. (B) Other screens displayed a graph of previous scores over time.

Figure 8

Identity change. (A) Flipsides of drinking showed images and text representing a positive or benefit of drinking with a negative or cost of drinking. (B) Memos allowed users to record video messages to watch at a later date. (C) I am … allowed users to select values of importance to them and then reflect on how these values might be affected by alcohol.

Figure 9

Goal setting. (A) Users could set an overarching goal for drinking less, create new goals, or get information about good goal setting. (B) “Your goals” allowed users to set new goals and see summary feedback about current goals. (C) Users could choose unit, spending, calorie, or alcohol-free day goals.