Related Experiment Video
Updated: Sep 26, 2026

Breakfast Habits among Schoolchildren in the City of Uruguaiana, Brazil
Published on: July 29, 2020
Prevalence of night work in the Brazilian employed population
Claudio José Dos Santos Júnior1, Frida Marina Fischer1
1Universidade de São Paulo, Faculdade de Saúde Pública, São Paulo, SP, Brazil.
Introduction:
Night work and extended work schedules are among the leading occupational health risk factors.
Objectives:
To estimate the prevalence of night work among the employed Brazilian population.
Methods:
Cross-sectional, population-based study using data from the 2019 Brazilian National Survey of Health. Individuals aged 15 years or older who belonged to the economically active employed population were included. The outcome was self-reported night work, assessed using a survey question on work performed between 8:00 p.m. and 5:00 a.m. Responses were recorded as 0 = no and 1 = yes. Prevalence estimates and their 95% CIs were calculated accounting for the complex survey design according to sociodemographic, occupational, and state-level characteristics. Associations were evaluated using the Rao-Scott adjusted Pearson chi-square test.
Results:
The national prevalence of night work was 13.3% (95% CI, 12.8%-13.9%), ranging from 5.8% in Acre to 16.6% in Rio de Janeiro. Night work was more frequent in urban areas (14.2%), among men (16.3%), and among higher-income individuals (15.5%). The highest prevalences were observed in the accommodation and food services (28.7%) and transportation, warehousing, and postal services (26.9%) sectors.
Conclusions:
Approximately one in seven workers in Brazil engaged in night work. The prevalence varied according to regional, sociodemographic, and occupational characteristics, with higher prevalences in sectors requiring continuous operations. These findings underscore the importance of monitoring work schedules and implementing policies to protect the health of workers exposed to night work.
Related Concept Videos
Substance Use Disorders Affecting Sleep
Understanding the concepts of physical dependence,...
Prevalence and Incidence
Prevalence indicates the proportion of individuals in a population who have a specific disease or health condition at a...
Insufficient Sleep and Sleep Deprivation
Sleep deprivation is a more severe form of sleep loss...
Quantifying Work
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Pharmacovigilance
This process, termed pharmacovigilance, aims to detect, evaluate, and minimize harmful effects related to medication use. The data collection for pharmacovigilance depends on spontaneous reporting systems, where healthcare professionals or patients voluntarily report suspected ADRs.
In some cases, there...

