Feasibility study
How to use a feasibility study when planning the evaluation of your digital health product.
This page is part of a collection of guidance on evaluating digital health products.
A feasibility study is a smaller version of a full-scale evaluation study. It is important to check in advance if the evaluation you have designed will work, which may mean carrying out a feasibility study. This is especially true for more expensive evaluations, such as comparative studies.
What to use it for
A feasibility study can be used after your product is developed (summative evaluation). It can help you to pilot your study design, recruitment and data collections methods. The main idea is to conduct a smaller-scale study recruiting participants similar to people you would want to use your digital product.
Pros
Benefits include:
- identifying any problems with the study before running a full-scale evaluation
- an opportunity to refine the design, which can decrease missing data
- testing the practicalities of implementing an intervention to avoid any technical challenges when assessing the digital product
Cons
Drawbacks include:
- additional time and effort
- may tell you that it is hard to recruit people but might not tell you why; to answer this, conduct qualitative studies with the participants
How to carry out a feasibility study
Many factors can affect whether you will be able to conduct your planned evaluation study, for example:
- cost
- timing
- participant burden
- likely response rates
- whether measuring something affects the outcome. For example, using a wearable to measure physical activity can sometimes influence participant’s behaviour
The questions you might want to consider in your feasibility study fall into two categories:
- feasibility – can the study design, procedures, and intervention be carried out
- acceptability – are the study design, procedures, and intervention appropriate from the perspective of the participant
These are closely linked. For example, if the study is not acceptable to your participants, then it might not be feasible to carry out.
Feasibility studies can help you answer questions like:
- is it possible to recruit participants to my study? You could answer this by looking at the recruitment rates
- once participants are in the study, do they stay in the study? You could answer this by looking at the retention rates
- are the participants willing to take part in follow-ups, including data collection? You could answer this question by looking at the survey completion rates
You could also look at the preliminary results of your outcome measures. As a feasibility study is on a small scale, you cannot conclude much from the results. However, you could look at the trends in your results and use the data to inform power calculations.
You could also include a qualitative component in the study that will help you to understand why some of the results were observed. For example, if you found low follow-up rates for some outcomes measures, you might want to ask the participants what made them skip or disengage from filling in a survey.
If you find that some parts of your study design are difficult to carry out or do not seem suitable for participants, you can refine and improve these aspects for your full-scale study.
A feasibility study tries to replicate the whole procedure of an evaluation, but you could also carry out smaller pilots of parts of an evaluation. For example, you could pilot a survey tool on its own.
Example: text messaging interventions to engage young people diagnosed with HIV with care
Trujillo and others (2020), Digital HIV Care Navigation for Young People Living With HIV in San Francisco, California: Feasibility and Acceptability Study
The team conducted a study assessing feasibility and acceptability of a text message-based intervention for young people living with HIV who experience issues with engaging with HIV care.
They used quantitative and qualitative methods to assess feasibility and acceptability of the intervention.
Feasibility using quantitative data was investigated by assessing participants’ engagement with the text messaging during the intervention. They categorised levels of engagement as high, medium and low.
Acceptability was assessed using qualitative interviews with a diverse sub-sample of participants. Researchers explored the participants’ overall experience of the text message intervention and the potential impact the intervention might have had on them.
The study received ethics approval from the University of California, San Francisco.
The feasibility study had 120 participants and 16 participants were interviewed. Most participants showed medium or high levels of engagement (50/120 (41.7%) and 26/120 (21.7%), respectively). The majority of participants found that the intervention added value to their lives, improved their engagement in HIV care and helped with medication adherence.
They concluded that the intervention was feasible and acceptable, and it may provide some improvements in users’ engagement with HIV care. However, based on the interviews, they identified potential challenges and barriers. For example, they found that providing the intervention soon after the HIV diagnosis might be less appropriate for some participants, because some people might find it overwhelming to discuss their HIV status so early on. Based on findings of the qualitative study, they provided some recommendations to refine the intervention.
More information and resources
CONSORT 2010 statement: extension to randomised pilot and feasibility trials. This explains what you should report when describing a pilot or feasibility study. It can also be used as a checklist when designing a pilot or feasibility study.
Defining Feasibility and Pilot Studies in Preparation for Randomised Controlled Trials: Development of a Conceptual Framework. This explains the difference between pilot and feasibility studies in preparation for a randomised controlled trial.
Maximising the impact of qualitative research in feasibility studies for randomised controlled trials: guidance for researchers. This explains how to design a qualitative study to explore uncertainties before running a full trial.
Examples of feasibility studies in digital health
Testing the feasibility of a mobile technology intervention promoting healthy gestational weight gain in pregnant women (txt4two) - study protocol for a randomised controlled trial. This study describes the plan for a feasibility study of a trial assessing mobile app intervention.
A Qualitative Evaluation of the Acceptability of a Tailored Smartphone Alcohol Intervention for a Military Population: Information About Drinking for Ex-Serving Personnel (InDEx) App. This qualitative study reports on acceptability and engagement with a mobile app intervention combined with text messaging.
DIAMOND (DIgital Alcohol Management ON Demand): a mixed methods feasibility. Researchers carried out a study assessing the feasibility of recruiting and keeping participants in a study looking at a digital intervention for harmful drinking. However, they only managed to recruit 7 participants. The qualitative component explored why this trial was not feasible.