I thank O'Flaherty & Capewell for indicating that two figures in
their paper were inaccurate. I look forward to seeing the correct graphs.
It will be interesting to see female mortality trends by deprivation as it
is fascinating that rate ratios for men and women produce what appear to
be identical graphs.
I also thank the authors for indicating that the trend lines in
Figure 2 are moving averages. I note in the text that the authors state
that they have used a 5 point moving average. I can see that this is a
prior moving average, which has resulted in the trend line being shifted
to the right. The line therefore lags the actual rates by about two years.
As a matter of presentation, and because the authors have used
multiplicative models, the rates in Figure 2 might have been better
presented on a logarithmic scale. This may have allowed the reader a
better visual inspection of rates at younger ages.
Finally, it is unusual to read a paper on small area deprivation
which does not make reference to the denominator population, it’s source
and reliability. Leyland [1] hinted that migration might be of relevance -
both to the number of deaths and the size of the population in which those
deaths occurred.
Scotland has seen a large influx of people from Eastern Europe (in
particular Poland) since 2004. These are mainly young adults seeking work.
The 2001 Census records 3,000 people living in Scotland who were born in
Poland. In 2007 this was estimated as 28,000 [2]. However, the true number
might be closer to 50,000 when non-registered Poles are included [3].
Migration could be an issue for the reliability of population estimates.
In 2000 251 deaths occurred in Scotland in which the country of birth
of the deceased was ‘Other European Union’, in 2007 the number of deaths
in this category was 512 [4]. All deaths which occur in Scotland are
recorded by the General Registrar regardless of whether the deceased
resides in Scotland. This does raise the question of whether the author’s
results would change had they restricted their analysis to deaths among
Scottish residents.
1. Leyland, A. H, Lynch, J. W (2009). Why has mortality from coronary
heart disease in young adults levelled off?. BMJ 339: b2515-b2515
Rapid Response:
Re: Author's Reply
I thank O'Flaherty & Capewell for indicating that two figures in
their paper were inaccurate. I look forward to seeing the correct graphs.
It will be interesting to see female mortality trends by deprivation as it
is fascinating that rate ratios for men and women produce what appear to
be identical graphs.
I also thank the authors for indicating that the trend lines in
Figure 2 are moving averages. I note in the text that the authors state
that they have used a 5 point moving average. I can see that this is a
prior moving average, which has resulted in the trend line being shifted
to the right. The line therefore lags the actual rates by about two years.
As a matter of presentation, and because the authors have used
multiplicative models, the rates in Figure 2 might have been better
presented on a logarithmic scale. This may have allowed the reader a
better visual inspection of rates at younger ages.
Finally, it is unusual to read a paper on small area deprivation
which does not make reference to the denominator population, it’s source
and reliability. Leyland [1] hinted that migration might be of relevance -
both to the number of deaths and the size of the population in which those
deaths occurred.
Scotland has seen a large influx of people from Eastern Europe (in
particular Poland) since 2004. These are mainly young adults seeking work.
The 2001 Census records 3,000 people living in Scotland who were born in
Poland. In 2007 this was estimated as 28,000 [2]. However, the true number
might be closer to 50,000 when non-registered Poles are included [3].
Migration could be an issue for the reliability of population estimates.
In 2000 251 deaths occurred in Scotland in which the country of birth
of the deceased was ‘Other European Union’, in 2007 the number of deaths
in this category was 512 [4]. All deaths which occur in Scotland are
recorded by the General Registrar regardless of whether the deceased
resides in Scotland. This does raise the question of whether the author’s
results would change had they restricted their analysis to deaths among
Scottish residents.
1. Leyland, A. H, Lynch, J. W (2009). Why has mortality from coronary
heart disease in young adults levelled off?. BMJ 339: b2515-b2515
2. http://www.gro-scotland.gov.uk/statistics/publications-and-
data/population-estimates/population-by-country-of-birth-and-nationality-
2004-2007.html (accessed 5 August 2009)
3. Polish immigrants swell Scotland's new baby boom.
http://news.scotsman.com/polesinscotland/Polish-immigrants-swell-Scotlands
-new.3297083.jp (accessed 5 August 2009)
4. Scotland's Population 2007 - The Registrar General's Annual Review
of Demographic Trends ISBN 978-1-874451-77-8
Competing interests:
None declared
Competing interests: No competing interests