tetano
Editor, Senior Moderator
Am J Epidemiol. 2017 Jun 30. doi: 10.1093/aje/kwx270. [Epub ahead of print]
[h=1]Heterogeneity in Estimates of the Impact of Influenza on Population Mortality: A Systematic Review.[/h] Li L, Wong JY, Wu P, Bond HS, Lau EHY, Sullivan SG, Cowling BJ.
[h=3]Abstract[/h] Influenza viruses are associated with substantial global burden of morbidity and mortality every year. Estimates of influenza-associated mortality often vary between studies due to differences in study settings, methods and measurement of outcomes. We reviewed 103 published articles assessing population-based influenza-associated mortality through searching PubMed and Embase, and identified considerable variation in the statistical methods used across studies. In studies using regression models with an influenza activity proxy, four approaches were applied to estimate the influenza-associated mortality. The estimates increased with age and ranged widely from -0.3-1.3 and 0.6-8.3 respiratory deaths per 100,000 population for children and adults to 4-119 respiratory deaths per 100,000 population for older adults. Meta-regression analysis identified that study design features were associated with the observed variation in estimates. The estimates increased with broader cause-of-death classification, and were higher for older adults than for children. The multiplier methods tended to produce lower estimates, while Serfling-type models were associated with higher estimates compared with other methods. No 'average' estimate of excess mortality could reliably be made due to the substantial variability of the estimates partially attributable to methodological differences in the studies. Standardization of methodology in estimation of influenza-associated mortality would permit improved comparisons in the future.
? The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
[h=4]KEYWORDS:[/h] epidemiology; excess mortality; influenza; systematic review
PMID: 28679157 DOI: 10.1093/aje/kwx270
[h=1]Heterogeneity in Estimates of the Impact of Influenza on Population Mortality: A Systematic Review.[/h] Li L, Wong JY, Wu P, Bond HS, Lau EHY, Sullivan SG, Cowling BJ.
[h=3]Abstract[/h] Influenza viruses are associated with substantial global burden of morbidity and mortality every year. Estimates of influenza-associated mortality often vary between studies due to differences in study settings, methods and measurement of outcomes. We reviewed 103 published articles assessing population-based influenza-associated mortality through searching PubMed and Embase, and identified considerable variation in the statistical methods used across studies. In studies using regression models with an influenza activity proxy, four approaches were applied to estimate the influenza-associated mortality. The estimates increased with age and ranged widely from -0.3-1.3 and 0.6-8.3 respiratory deaths per 100,000 population for children and adults to 4-119 respiratory deaths per 100,000 population for older adults. Meta-regression analysis identified that study design features were associated with the observed variation in estimates. The estimates increased with broader cause-of-death classification, and were higher for older adults than for children. The multiplier methods tended to produce lower estimates, while Serfling-type models were associated with higher estimates compared with other methods. No 'average' estimate of excess mortality could reliably be made due to the substantial variability of the estimates partially attributable to methodological differences in the studies. Standardization of methodology in estimation of influenza-associated mortality would permit improved comparisons in the future.
? The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
[h=4]KEYWORDS:[/h] epidemiology; excess mortality; influenza; systematic review
PMID: 28679157 DOI: 10.1093/aje/kwx270