Longitudinal Studies

  1. definition
  2. examples and/or illustrations
  3. other useful sources
  4. bibliography


“Longitudinal study: A study in which individuals are followed over time, and compared with themselves at different times, to determine, for example, the effect of aging on some measured variable. Longitudinal studies provide much more persuasive evidence about the effect of aging than do cross-sectional studies.”

-University of California, Berkeley. “Glossary of Statistical Terms.” http://www.stat.berkeley.edu/~stark/SticiGui/Text/gloss.htm. [Accessed 22 September 2013].

“A cross-sectional study is an observational one. This means that researchers record information about their subjects without manipulating the study environment…The defining feature of a cross-sectional study is that it can compare different population groups at a single point in time…The benefit of a cross-sectional study design is that it allows researchers to compare many different variables at the same time. We could, for example, look at age, gender, income and educational level in relation to walking and cholesterol levels, with little or no additional cost. However, cross-sectional studies may not provide definite information about cause-and-effect relationships. This is because such studies offer a snapshot of a single moment in time; they do not consider what happens before or after the snapshot is taken. A longitudinal study, like a cross-sectional one, is observational. So, once again, researchers do not interfere with their subjects. However, in a longitudinal study, researchers conduct several observations of the same subjects over a period of time, sometimes lasting many years. The benefit of a longitudinal study is that researchers are able to detect developments or changes in the characteristics of the target population at both the group and the individual level. The key here is that longitudinal studies extend beyond a single moment in time. As a result, they can establish sequences of events…Therefore, a longitudinal study is more likely to suggest cause-and-effect relationships than a cross-sectional study by virtue of its scope.”

-Institute for Work and Health. 2009. “Cross-sectional vs. longitudinal studies.” At Work Issue 55. http://www.iwh.on.ca/wrmb/cross-sectional-vs-longitudinal-studies. [Accessed 24 September 2013].

Definition: A longitudinal study refers to an investigation where participant outcomes and possibly treatments or exposures are collected at multiple follow-up times.”

-University of Washington. “Longitudinal Research.” faculty.washington.edu/heagerty/Courses/…longitudinal/…/LDAchapter.p…


Examples and/or Illustrations

“Cross-sectional studies provide snapshots of adaptation to a new environment. Static images cannot, however, do justice to resettlement, a moving sequence of challenges and adaptive responses whose importance is conditioned by time…Besides addressing possible changes in salience, longitudinal research also facilitates theoretical advance by making it possible to study antecedent, concurrent and consequent relationships. The status of a variable at one particular point in time may affect not only subsequent levels of the same variable, but of other variables as well. Baseline measures of psychological states such as depression act as a proxy for predisposition, the extent to which vulnerability and experience combine to produce psychological disorder. Although mental health is often considered an independent variable, it may also act as an important predictor of psychosocial variables involved in the resettlement process. For example, it is widely assumed that experiences with discrimination can jeopardize mental health. On the other hand, it is possible that mental disorder creates heightened interpersonal sensitivity and possible misinterpretation of social clues, or creates a predisposition towards mistaken attributions. According to data from our RRP study, about one quarter of the refugees experienced discrimination, either personally while at school or in the workplace, or in public settings (Noh, Beiser, Kaspar, Hou, & Rummens, 1999). Experiencing discrimination was a powerful predictor of subsequent depression, but the reverse was not true (Beiser & Wickrama, n.d.). Aside from this contribution to theory, our data showed that early integration militated against subsequent experiences of discrimination and also against the occurrence of depression by the end of the refugee’s first decade in Canada. These findings have implications for policy, suggesting that an early investment in language training, cultural orientation programs and instruction in needed skills such as the use of banks, understanding tenancy rights and the like are likely to produce long-term benefit (Beiser, 2003). The concept of time perspective as a coping strategy is one of the more original contributions the RRP has made to the mental health literature. The study’s longitudinal data, which provide an opportunity to study patterns of time perspective and shifting relationships between time perspective and mental health, have enriched theory about how people handle overwhelming stress.”

– Beiser, Morton. 2006. “Longitudinal Research to Promote Effective Refugee Resettlement.” Transcultural Psychiatry 43(1): 56-71.

“The mental health of resettled refugees is poorer than that of the general population. Resettlement to a new country and culture can present social challenges, such as building new social support networks and gaining suitable employment. Social factors in resettlement represent modifiable targets for public health policies and interventions to improve refugee mental health. Despite implicating individual social factors, previous research has failed to adjust for potential confounding by investigating many social determinants simultaneously. Additionally, there is a dearth of research causally and temporally linking social determinants and mental health with longitudinal analysis… Post-displacement social factors such as employment, financial status, and satisfaction with accommodation were important determinants of refugee mental health. Changes in these social determinants could improve refugee mental health. Public health policies and interventions could target vulnerable refugee subpopulations and seek to tackle modifiable post-displacement social factors. A key limitation of this study was the self-reported nature of the variables, introducing the potential for reverse causality. Additionally, new refugees are a difficult population to retain for longitudinal follow-up; loss to follow-up was substantial but similar to that in previous studies.”

– Campbell, Mark. 2012. “Social Determinants of Mental Health in New Refugees in the UK: Cross-section and Longitudinal Analyses.” The Lancet 380(3): S27.


Other Useful Sources

Journal of Refugee Studies 20(2): Special Issue on Refugee Research Methodologies.

Menard, Scott W. 2002. Longitudinal Research. Thousand Oaks CA: Sage Publications, 2nd ed.

Newsom, Jason T., Richard N. Jones, Scott M. Hofer. 2012. Longitudinal Data Analysis: A Practical Guide for Researchers in Aging, Health, and Social Sciences. New York: Routledge.

Schmidt, Anna. 2007. “‘I know what you’re doing’, reflexivity and methods in Refugee Studies.” Refugee Survey Quarterly 26(3): 82-99.

UK Home Office and UK Border Agency. Survey of New Refugees: 2005-2009. http://discover.ukdataservice.ac.uk/catalogue/?sn=6556.

Voutira, Eftihia and Giorgia Dona. 2007. “Refugee Research Methodologies: Consolidation and Transformation of a Field.” Journal of Refugee Studies 20(2): 163-171.



Beiser, Morton. 2006. “Longitudinal Research to Promote Effective Refugee Resettlement.” Transcultural Psychiatry 43(1): 56-71.

Correa, Ignacio-Velez, Sandra M. Gifford, and Adrian G. Barnett. 2010. “Longing to Belong: Social Inclusion and Wellbeing Among Youth with Refugee Backgrounds in the First Three Years in Melbourne, Australia.” Social Science & Medicine 71(8): 1399-1408.

Campbell, Mark. 2012. “Social Determinants of Mental Health in New Refugees in the UK: Cross-section and Longitudinal Analyses.” The Lancet 380(3): S27.

Cebulla, A., Daniel, M. and Zurawan, A. 2010. Spotlight on refugee integration: findings from the Survey of New Refugees in the United Kingdom, Research Report 37, London: Home Office.

Clark-Kazak, Christina. 2009. “Representing Refugees in the Life Cycle: A Social Age Analysis of United Nations High Commissioner for Refugees Annual Reports and Appeals 1999-2008.” Journal of Refugee Studies 22(3): 302-322.

Daniel, M. and Zurawan, A. 2010. Summary of the Survey of New Refugees, December 2005 – March 2009, Research Report 35, London: Home Office.

Daniel, M., Devine, C., Gillespie, R., Pendry, E. and Zurawan, A. 2010. Helping new refugees integrate into the UK: baseline data analysis from the Survey of New Refugees, Research Report 36, London: Home Office.

Jacobsen, K. and Landau L. 2003. “Researching Refugees: Some Methodological and Ethical Considerations in Social Science and Forced Migration.” Working Paper 90. Geneva: UNHCR.

Lie, Birgit. 2004. “The Psychological and Social Situation of Repatriated and Exiled Refugees: A Longitudinal, Comparative Study.” Scandinavian Journal of Public Health 32(3): 179-187.

Rousseau, Cecile and Aline Drapeau. 2003. “Are Refugee Children an At-Risk Group? A Longitudinal Study of Cambodian Adolescents.” Journal of Refugee Studies 16(1): 67-81.

Stewart, Emma. 2004. “Deficiencies in UK Asylum Data: Practical and Theoretical Challenges.” Journal of Refugee Studies 17(1): 29-49.

Williams, Meagan and Sandra Thompson. 2011. “The Use of Community-Based Interventions in Reducing Morbidity from the Psychological Impact of Conflict-Related Trauma Among Refugee Populations: A Systematic Review of the Literature.” Journal of Immigrant and Minority Health 13(4): 780-794.