Series: Practical guidance to qualitative research. Part 6: Longitudinal qualitative and mixed-methods approaches for longitudinal and complex health themes in primary care research

Figures & data

Table 1. Longitudinal qualitative research: comparison of recurrent cross-sectional versus longitudinal analysis. Based on Grossoehme et al., [22].

Considerations	Recurrent cross-sectional analysis	Longitudinal analysis
Research focus [findings]	Describe the difference between time points.	Describe how process or experience changes over time.
Sample considerations	The cohort at each time may be the same or different. May be preferred if sample is highly transient or has high mortality over study duration.	Must maintain same cohort.
Theoretical approach	Determined by research question; used consistently throughout the study.	Determined by research question; used consistently throughout the study.
Level of data analysis	Whole sample or subsamples.	Individual people or individual groups, e.g. families.
Timing of analysis	May analyze as each time point is completed.	Must wait until data collection is complete for all time points.

Table 2. Three common mixed-methods designs, based on Hong et al., and O’Cathain et al., [30,31].^a

Design	Timing	Purpose
Convergent	QUAL and QUAN components are usually concomitant	Examine the same phenomenon by interpreting QUAL and QUAN results (bringing data analysis together at interpretation stage), or by integrating QUAL and QUAN datasets (e.g. data on same cases), or by transforming data (e.g. quantization of qualitative data).
Sequential explanatory	Results phase 1 – QUAN component inform phase 2 – QUAL component	Explain QUAN results using QUAL findings. E.g. QUAN results guide selection of QUAL data sources and data collection and QUAL findings contribute to interpretation of QUAN results.
Sequential exploratory	Results phase 1 – QUAN component inform phase 2 – QUAL component	Explore, develop and test an instrument (or taxonomy), or a conceptual framework (or theoretical model). E.g. QUAL findings inform QUAN data collection and QUAN results allow statistical generalization of QUAL findings.

^aQUAN: quantitative; QUAL: qualitative.

Table 3. Recommendations for good reporting of a mixed methods study (GRAMMS) [31].

Describe the justification for using a mixed-methods approach to the research question the design in terms of the purpose, priority and sequence of methods each method in terms of sampling, data collection and analysis where integration has occurred, how it has occurred and who has participated in it any limitation of one method associated with the presence of the other method any insights gained from mixing or integrating methods

Table 4. Challenges and strategies in longitudinal qualitative research and mixed-methods research, based on Calman et al., and Creswell et al., [14,15].

	Longitudinal qualitative research	Mixed-methods research	Strategies
Funding	Extensive time and resources needed Funders may be unfamiliar with longitudinal qualitative research	Extensive time and resources needed	Provide clear rationale and make a strong case for the added value of the approach for this health theme
Participants and sampling	Intrusion into people’s lives, distortion of experience or dependency due to long-lasting personal relationships with researchers. Attrition due to increasing burdens of health problems or research procedures over time	Convergent design: adequate sample sizes, comparable samples, consistent unit of analysis across databases. Sequential design: deciding on what results from phase 1 to use in phase 2, samples and sample sizes	Adequate time in project plans for project management and communication (including support) with participants
Researchers	Burden due to involvement in sustained relationship with participants over time	Combining quantitative and qualitative components requires knowledge across multiple research methods	Adequate research team, teamwork, debriefing, support, reflexivity
Research team	Large research teams: confidentiality issues over time, different perspectives, researchers who were not involved in data-collection may participate in data-analysis	Multidisciplinary teams: different methodological and philosophical approaches and writing styles	Team leaders anticipate challenges and benefits of teamwork Good teamwork, reflexivity, communication
Data-collection, analysis and interpretation	Large data set requires extensive time for planning, logistics, keeping up to date with participants Complex analyses at multiple levels: within each case and as comparison between cases	Findings may conflict or be contradictory, requiring collecting more data or revisiting databases Unequal emphasis on datasets, accuracy or validity of each dataset Dilemma’s in combining quantitative and qualitative research philosophies	Good project management and timing of research steps Flexibility and responsiveness to data, emerging analysis, interpretation Reflexivity
Publishing	Researchers need to justify different qualitative procedures but encounter page and word limitations in journals	Researchers need to justify qualitative and quantitative procedures but encounter page and word limitations in journals	Use tables or figures of procedures and creative ways to present material Choose journals who are familiar with or open to the approach

Table 5. Sources for further reading on longitudinal qualitative research and mixed-methods research.

Longitudinal qualitative research Balmer D, Richards BF. Longitudinal qualitative research in medical education Perspect Med Educ. 2017;6:306–310. Calman L, Brunton L, Molassiotis A. Developing longitudinal qualitative designs: lessons learned and recommendations for health services research. BMC Med Res Methodol. 2013;13:14. Derrington M. Qualitative research methods: qualitative longitudinal methods. Thousand Oaks (CA): Sage; 2019. Grossoehme D, Lipstein E. Analysing longitudinal qualitative data: the application of trajectory and recurrent cross-sectional approaches. BMC Res Notes. 2016;9(1):1–5. Nevedal A, Ayalon L, Briller S. A qualitative evidence synthesis review of longitudinal qualitative research in gerontology. Gerontologist. 2019;59:e791–e801. Thomson R, McLeod J. New frontiers in qualitative longitudinal research: an agenda for research. J Soc Res Methodol Int. 2015;18:243–250. Mixed-methods research: Creswell JW, Hirose M. Mixed methods and survey research in family medicine and community health. Fam Med Com Health. 2019;7:e000086. Doi:10.1136/fmch-2018-000086. Creswell JW, Klassen AC, Plano Clark VL, Smith KC for the Office of Behavioural and Social Sciences Research. Best practices for mixed methods research in the health sciences. 2011. National Institutes of Health. https://obssr.od.nih.gov/sites/obssr/files/Best_Practices_for_Mixed_Methods_Research.pdf. Creswell JW, Plano Clark VL. Designing and conducting mixed methods research. 3rd edn. Los Angeles (CA): Sage; 2018. Kaur N, Vedel I, El Sherif R, et al. Practical mixed methods strategies used to integrate qualitative and quantitative methods in community-based primary health care research. Fam Pract. 2019;36:666-671. Doi:10.1093/fampra/cmz010. Mixed Methods Program University of Michigan. http://www.mixedmethods.org.. Schoonenboom J, Johnson R. How to construct a mixed methods research design. Köln Z Soziol. 2017;69:107–131. Vedel I, Kaur N, Hong QN, et al. Why and how to use mixed methods in primary health care research. Fam Pract. 2019;36:365–368. Doi:10.1093/fampra/cmy127.

Grossoehme D, Lipstein E. Analyzing longitudinal qualitative data: the application of trajectory and recurrent cross-sectional approaches. BMC Res Notes. 2016;9:136.

 PubMedGoogle Scholar

Hong Q, Pluye P, Fàbregues S, et al. Mixed Methods Appraisal Tool (MMAT), version; 2018 [Internet] [cited 2021 Sep 15]. Available from: http://mixedmethodsappraisaltoolpublic.pbworks.com/w/file/fetch/127916259/MMAT_2018_criteria-manual_2018-08-01_ENG.pdf.

 Google Scholar

O'Cathain A, Murphy E, Nicholl J. The quality of mixed methods studies in health services research. J Health Serv Res Policy. 2008;13(2):92–98.

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Creswell J, Klassen A, Plano Clark V, et al. Research for the Office of Behavioral and Social Sciences. Best practices for mixed methods research in the health sciences, 2011 [Internet] [cited 2021 Sep 15]. Available from: https://obssr.od.nih.gov/research-resources/mixed-methods-research.

 Google Scholar

Calman L, Brunton L, Molassiotis A. Developing longitudinal qualitative designs: lessons learned and recommendations for health services research. BMC Med Res Methodol. 2013;13:14.

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