Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings?
Abstract Background Anaemic status is determined by haemoglobin using the HemoCue system or haematocrit measurements, and a threefold conversion is commonly used to equate the two measures (haemoglobin = haematocrit/3). The validity of this conversion in malaria endemic settings was assessed. Method...
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ftdoajarticles:oai:doaj.org/article:b8f09e74d6c641c78cccb2ed789fa5b7 2023-05-15T15:15:53+02:00 Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings? Owusu-Agyei Seth Drakeley Chris J Carneiro Ilona A Mmbando Bruno Chandramohan Daniel 2007-05-01T00:00:00Z https://doi.org/10.1186/1475-2875-6-67 https://doaj.org/article/b8f09e74d6c641c78cccb2ed789fa5b7 EN eng BMC http://www.malariajournal.com/content/6/1/67 https://doaj.org/toc/1475-2875 doi:10.1186/1475-2875-6-67 1475-2875 https://doaj.org/article/b8f09e74d6c641c78cccb2ed789fa5b7 Malaria Journal, Vol 6, Iss 1, p 67 (2007) Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 article 2007 ftdoajarticles https://doi.org/10.1186/1475-2875-6-67 2022-12-31T12:31:13Z Abstract Background Anaemic status is determined by haemoglobin using the HemoCue system or haematocrit measurements, and a threefold conversion is commonly used to equate the two measures (haemoglobin = haematocrit/3). The validity of this conversion in malaria endemic settings was assessed. Methods Concurrent measures of haemoglobin and centrifuged haematocrit in children aged 6–59 months were compared by modelling the difference between the two measures against their average. A random effects linear regression of the difference of the measures on their average was used to describe the line of best agreement and 95% limits of agreement for these two measures over a range of values after adjusting for statistically significant covariates. Results There was a consistent bias between the two measures, with haemoglobin less than haematocrit/3 in 87% (899/1,030) of observations. This difference was non-uniform, decreasing with the average measure, i.e. less difference at higher haemoglobin and haematocrit values. In these studies, use of haematocrit would have underestimated the prevalence of anaemia by misclassifying 10% (89/920) of individuals with haemoglobin < 11 g/dl, 66% (252/380) of individuals with haemoglobin < 8 g/dl and 100% (23/23) of individuals with haemoglobin < 5 g/dl. The mean difference between the measures was greater in males than females, increased with age between 6–59 months, and was greater in the wet than dry season suggesting that the relationship between haemoglobin and haematocrit may be modified by exposure to malaria. Conclusion The regression model indicated that the standard threefold conversion from haematocrit to haemoglobin underestimates the prevalence of haemoglobin < 11 g/dl in children under five years of age in malaria endemic settings. This bias was more acute for more severe anaemia defined by haemoglobin < 8 g/dl and haemoglobin < 5 g/dl. This has important implications for the comparability of studies using these different measures. Direct determination ... Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic Malaria Journal 6 1 |
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Directory of Open Access Journals: DOAJ Articles |
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English |
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Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 |
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Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 Owusu-Agyei Seth Drakeley Chris J Carneiro Ilona A Mmbando Bruno Chandramohan Daniel Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings? |
topic_facet |
Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 |
description |
Abstract Background Anaemic status is determined by haemoglobin using the HemoCue system or haematocrit measurements, and a threefold conversion is commonly used to equate the two measures (haemoglobin = haematocrit/3). The validity of this conversion in malaria endemic settings was assessed. Methods Concurrent measures of haemoglobin and centrifuged haematocrit in children aged 6–59 months were compared by modelling the difference between the two measures against their average. A random effects linear regression of the difference of the measures on their average was used to describe the line of best agreement and 95% limits of agreement for these two measures over a range of values after adjusting for statistically significant covariates. Results There was a consistent bias between the two measures, with haemoglobin less than haematocrit/3 in 87% (899/1,030) of observations. This difference was non-uniform, decreasing with the average measure, i.e. less difference at higher haemoglobin and haematocrit values. In these studies, use of haematocrit would have underestimated the prevalence of anaemia by misclassifying 10% (89/920) of individuals with haemoglobin < 11 g/dl, 66% (252/380) of individuals with haemoglobin < 8 g/dl and 100% (23/23) of individuals with haemoglobin < 5 g/dl. The mean difference between the measures was greater in males than females, increased with age between 6–59 months, and was greater in the wet than dry season suggesting that the relationship between haemoglobin and haematocrit may be modified by exposure to malaria. Conclusion The regression model indicated that the standard threefold conversion from haematocrit to haemoglobin underestimates the prevalence of haemoglobin < 11 g/dl in children under five years of age in malaria endemic settings. This bias was more acute for more severe anaemia defined by haemoglobin < 8 g/dl and haemoglobin < 5 g/dl. This has important implications for the comparability of studies using these different measures. Direct determination ... |
format |
Article in Journal/Newspaper |
author |
Owusu-Agyei Seth Drakeley Chris J Carneiro Ilona A Mmbando Bruno Chandramohan Daniel |
author_facet |
Owusu-Agyei Seth Drakeley Chris J Carneiro Ilona A Mmbando Bruno Chandramohan Daniel |
author_sort |
Owusu-Agyei Seth |
title |
Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings? |
title_short |
Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings? |
title_full |
Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings? |
title_fullStr |
Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings? |
title_full_unstemmed |
Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings? |
title_sort |
haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria-endemic settings? |
publisher |
BMC |
publishDate |
2007 |
url |
https://doi.org/10.1186/1475-2875-6-67 https://doaj.org/article/b8f09e74d6c641c78cccb2ed789fa5b7 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
Malaria Journal, Vol 6, Iss 1, p 67 (2007) |
op_relation |
http://www.malariajournal.com/content/6/1/67 https://doaj.org/toc/1475-2875 doi:10.1186/1475-2875-6-67 1475-2875 https://doaj.org/article/b8f09e74d6c641c78cccb2ed789fa5b7 |
op_doi |
https://doi.org/10.1186/1475-2875-6-67 |
container_title |
Malaria Journal |
container_volume |
6 |
container_issue |
1 |
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1766346219823562752 |