By M. Wanat (Infectious Diseases Research Group, University of Oxford), A.M. Boylan (Centre for Evidence Based Medicine, University of Oxford), A. Borek (Infections & Acute Care Research Group, University of Oxford) 

Reference: Wanat, M, Boylan, A-M & Borek, A. Value, challenges and practical considerations when designing, conducting and analysing a longitudinal qualitative study in family medicine | Family Medicine and Community Health (bmj.com). 

Longitudinal qualitative research (LQR) involves multiple data collection points and is uniquely focused on exploring temporality of experiences. It can provide insights into the nature, causes and consequences of change as well as identifying continuity, stability and lack of change. While it is being increasingly used in applied health research, it is relatively underutilised in family medicine. Therefore, primary care researchers may be unsure about how to go about planning and conducting a longitudinal qualitative study in family medicine, and about the value of such design.

To make this task a little less daunting, this paper outlines key considerations and choices available when designing, conducting and analysing LQR in family medicine. We focus on five key areas and steps: 

1) Deciding on the length of data collection, and timing and number of interviews; for example, researchers may consider whether the data collection points should be around researcher-led or participant-led key ‘events’ or at pre-established intervals.

2) Planning recruitment: attrition versus oversampling; for example, researchers need to carefully balance between aiming for a sufficient number of participants, planning for attrition of participants over time, and avoiding unnecessary oversampling (and collecting unmanageable data).

3) Approaching data collection: asking the same or different questions over time; for example, researchers need to decide whether they want to explore similar or different topics at different time-points over time, as appropriate for their research aims and the topic.

4) Planning and conducting the analysis, and writing-up findings; for example, researchers may consider whether they need to analysing and report the data at each time point, comparing between time-points, or whether they focus on trajectories (e.g. following individual or groups of participants). 

5) Conducting ethical LQR; researchers need to consider a number of ethical issues, discussed the article, as these are particularly important due to immersive and prolonged approach in LQR.

The value of LQR 

There is great value in using LQR in family medicine. LQR’s focus on change and continuity lends itself well to the health care context and to primary care.  Specifically, LQR can illuminate patients’ experience of both health and primary care services over time, and explore the transition process from the perspective of individuals (including patients, healthcare professionals and policy makers) and organisations. It can help us understand the process of implementing new practices in primary care in the context of clinical trials and in routine clinical care. It can also give valuable insight into the relationship between individual experiences and historical change (e.g. the COVID-19 pandemic). Drawing on wider applied healthcare research and examples from family medicine, we showcase the value of LQR in this particular setting. 

Thus, we hope that by reading this article, readers will have a better understanding of:

• the decisions they may face when designing and conducting LQR 
• the value of using this design and its possible contributions to family medicine 
• how to use this design in a rigorous and appropriate way

We hope that the article will be of interest to both novice and more experienced researchers who may want to use this design in their own studies or who may want to better understand already published examples of LQR. 

Conflict of Interest: None declared