Research methodology topics: Cohort studies or prospective and retrospective cohort studies

Abstract

In health sciences, the epidemiological method can be divided into descriptive and analytical epidemiology and the latter being divided into observational (cross-sectional study, case-control study and cohort study) and experimental studies. Cohort studies may be retrospective or prospective, and both assume that the researcher will follow a population over time to seek a possible association between exposure (s) and outcome(s). These types of studies have as advantages the possibility of measuring several exposure factors and outcomes, both primary and secondary, for both relatively frequent outcomes and rare exposure factors. However, they are often long and therefore expensive studies. They have as main biases those of selection, memory and information. These are studies that may point to statistical associations between exposure and outcome that need other models to prove the casualty of these associations.

Prevalence of childhood obesity in Brazil: systematic review and meta-analysis

“…Cohort studies are expensive due to the time required for follow-up and the large sample size, a possible explanation for the lower number of studies included, and are more prone to losses of follow-up than other types of studies. 78 …”

Mapeamento do excesso de peso em gestantes e prematuridade: uma revisão de escopo

“…Também é possível observar que, a maior parte dos estudos são de coorte, ou seja, nível 3B de evidência, apontando uma qualidade razoável das investigações e mostrando evidências consistentes acerca da pergunta de pesquisa (Camargo et al, 2019).…”

Do depressive symptoms among pregnant women assisted in Primary Health Care services increase the risk of prematurity and low birth weight?

“…This prospective cohort study was conducted in the mid-south region of the state of São Paulo, Brazil ( 12 ) .…”