Volume 48 - Article 28 | Pages 829–848  

Age reporting for the oldest old in the Brazilian COVID-19 vaccination database: What can we learn from it?

By Cássio M. Turra, Fernando Fernandes, Júlia Almeida Calazans, Marília R. Nepomuceno

Abstract

Background: Age misreporting affects population estimates at older ages. In Brazil, every citizen must be registered and show an identity document to vaccinate against COVID-19. This requirement to present proof of age provides a unique opportunity for measuring the oldest-old population using novel administrative data.

Objective: To offer critically assessed estimates of the Brazilian population aged 80 and older based on data from the vaccination registration system (VRS). To uncover discrepancies between the number of vaccinated oldest-old people and the projections used to estimate target populations for COVID-19 vaccination.

Methods: We calculate data quality indicators based on data from the VRS – namely, 100+/80+ and 90+/80+ population proportions, sex ratios, and the Myers blended index – and compare them to those based on data on target populations from Brazilian censuses and demographic projections, and from Sweden – a country with high-quality data. We also estimate vaccination coverage ratios using population projections adjusted to excess deaths as the denominators.

Results: Requiring documentation reduces age heaping, age exaggeration, and sex ratios marginally. However, it cannot solve the problem of the misreporting of birth dates due to the absence of long-standing birth registration systems in Brazil, particularly in the northern and central regions. In addition, we find a mismatch between the projected populations and numbers of vaccinated people across regions.

Conclusions: Despite improvements in data quality in Brazil, we are still not confident about the accuracy of age reporting among the oldest old in the less advantaged Brazilian regions. The postponement of the 2020 census reduced the ability of authorities to define the target populations for vaccinations against COVID-19 and other diseases.

Contribution: This is the first study to compare population estimates for the oldest old in administrative data and census data in Brazil. Age misreporting resulted in discrepancies that may have compromised the efficacy of the COVID-19 vaccination campaign.

Author's Affiliation

• Cássio M. Turra - Universidade Federal de Minas Gerais (UFMG), Brazil EMAIL
• Fernando Fernandes - Universidade Federal de Minas Gerais (UFMG), Brazil EMAIL
• Júlia Almeida Calazans - Universidade Federal de Minas Gerais (UFMG), Brazil EMAIL
• Marília R. Nepomuceno - Max-Planck-Institut für Demografische Forschung, Germany EMAIL

Other articles by the same author/authors in Demographic Research

World population aging as a function of period demographic conditions
Volume 48 - Article 13

Assessing the quality of education reporting in Brazilian censuses
Volume 42 - Article 15

Mortality selection among adults in Brazil: The survival advantage of Air Force officers
Volume 37 - Article 41

The number of centenarians in Brazil: Indirect estimates based on death certificates
Volume 20 - Article 20

Most recent similar articles in Demographic Research

The impact of the COVID-19 pandemic on mortality in Uruguay from 2020 to 2022
Volume 51 - Article 29    | Keywords: COVID-19, excess mortality, life expectancy, Uruguay

The impact of the COVID-19 pandemic on women’s care work and employment in the Middle East and North Africa
Volume 51 - Article 15    | Keywords: care work, COVID-19, Middle East, North Africa, women's employment

Trajectories of US parents’ divisions of domestic labor throughout the COVID-19 pandemic
Volume 51 - Article 12    | Keywords: childcare, COVID-19, division of labor, fathers, gender, housework, mothers

Data errors in mortality estimation: Formal demographic analysis of under-registration, under-enumeration, and age misreporting
Volume 51 - Article 9    | Keywords: age misreporting, data errors, formal demography, mortality

Lessons from the pandemic: Gender inequality in childcare and the emergence of a gender mental health gap among parents in Germany
Volume 51 - Article 3    | Keywords: COVID-19, division of childcare, exhaustion, gender role attitudes, loneliness, mental health, pandemic, stress