Longitudinal Studies

Studies that cover a long period of time often comprise different methodological approaches. A common way of proceeding in longitudinal research is to collect a set of data at the study’s beginning and then repeatedly gather data on the same topic throughout the course of the study. Such following up methods could include the same individuals (panel studies) or replicate earlier research with new population in a similar context (trend studies). There are also case studies, which can be based on life stories of one or few individuals.

Longitudinal studies are especially effective in tracking societal conditions and can thus have an important impact on society. Longitudinal studies can be retrospective, by requesting people to look back and reflect on themselves across the life span. They can also be prospective, meaning that they can focus on peoples thinking and predictions about a possible or imaginable futures. When it comes to research on language use, personal life trajectories are especially appropriate for the understanding of linguistic development, habits and attitudes. Hence, longitudinal studies can be designed as to both reflect and challenge prevailing or changing ideologies in society.

In sociolinguistic research, longitudinal studies have been used to observe language variation and language change in the individual as well as in society – both in relation to national minority languages and to migration contexts. For instance, in the Catalan context, Woolard (2011) conducted a panel longitudinal sociolinguistic study and re-contacted a group of bilingual Spanish-Catalan speakers she first interviewed as high-school students in Barcelona, some 20 years earlier. She found out that their fluency in Catalan had increased substantially as they progressed to adulthood. We can find another example in the Swedish context were Ahlgren and Rydell (2020) investigated, in a trend longitudinal study, how different individuals enrolled in the programme of Swedish for Immigrants experienced language learning in the backdrop of societal and institutional changes over a period of 15 years.

In the EquiLing research project

Our project runs over a period of four years (2020–2024) and includes four different research groups, from Catalonia, the Basque Country, Galicia and Madrid. The project provides a wide perspective, with cross-sectional observations and analysis of multilingual speakers in different social and educational spaces.

  • The EquiLing project is retrospective by encouraging participants to look back and reflect on their experiences of language use, for instance by reconstructing their linguistic biographies trajectories. Moreover, we observe how the participant’s understanding of their linguistic trajectories change at different moments of the research project and how they think about their future. The project is also prospective by collecting new ethnographic data and adopting an action-research approach as to develop strategies to act on inequality and asymmetric power relations.
  • A pronounced goal of the project is to create a more inclusive and egalitarian sociolinguistic order in society. Such transformation is something that may take long time, and our expectation is that our project will have an important impact on people’s attitudes and behaviors in the academic world and in the wider society, not only during the project, but also in the future.

To know more

Thomson, R. & Holland, J. (2003). Hindsight, foresight and insight: The challenges of longitudinal qualitative research, International Journal of Social Research Methodology, 6:3, 233–244.

Sankoff, G. (2013). Longitudinal Studies. The Oxford Handbook of Sociolinguistics. Oxford: Oxford University Press.

Ahlgren, K. & Rydell, M. (2020). Continuity and change: migrants’ experience of adult language education in Sweden. European Journal for Research on the Education and Learning of Adults, 11:2, 399–414.  

Vila, F. X., Ubalde, J., Bretxa. V. & Comajoan-Colomé, L. (2019). Changes in language use with peers during adolescence: a longitudinal study in Catalonia, International Journal of Bilingual Education and Bilingualism, 23:9, 1158-1173.

Woolard, K. (2011). Is there linguistic life after high school? Longitudinal changes in the bilingual repertoire in metropolitan Barcelona, Language in Society 40, 617–648.

Longitudinal studies are research projects that involve observing individuals, or groups of people, over a certain period of time, ranging from a few months to several years or even across generations. Longitudinal projects allow the study of people’s experiences, behaviors, attitudes and emotions in relation to ideological discourses and social development. They allow researchers to observe changes, or stability, in humans throughout their lives, as they interact with others, experience struggles, and enjoy their successes.