Feeds

Is heart rate correlated with birth order?

Beating to a different tune

Top three mobile application threats

Also in this week's column:

Is heart rate correlated with birth order?

Asked by Lotti Otunnu of Lagos, Nigeria

Those who continue to believe that heart rate is correlated with birth order may not realise that such a notion is based upon only one study. The study dates back to the 1940s and involved 778 children from the town of Hagerstown, Maryland.

During routine public health screening, the heart rates of the 400 boys and 378 girls who attended one school were measured. It was found that the first-born and second-born children had statistically significantly shorter cardiac cycles, diastole, and systole compared with children who were third-born, fourth-born, or born even later in families (it's well to remember that families were often larger in those days). Strangely too, this heart rate difference was found to be greater in boys than in girls.

The heart is continually filling and emptying with blood. The "cardiac cycle" is the term for this process and consists of the complete cardiac diastole, systole, and all time intervals in-between. "Diastole" is the time at which the filling of the heart's ventricles with blood occurs. "Systole" is the contraction time at which the emptying of the heart’s ventricles occurs.

In the Hagerstown study there was no explanation for the curious finding of heart rate being associated with birth order. However, speculation included a possible previously unknown mysterious maternal factor appearing in the second, third, or subsequent pregnancy having a bearing upon the development of the child's heart.

A US Public Health Service study found no corroboration for the Hagerstown finding. A single article, authored by Antonio Ciocco, was published in Human Biology in 1943. Since then, research has failed to again find the association found in Hagerstown or anything similar.

For example, birth order was found to have no relationship to blood pressure in a 1980 study in the The American Journal of Epidemiology. That study was undertaken by Dr M Higgins and five colleagues from the US National Heart, Lung, and Blood Institute in Bethesda, Maryland, about 61 miles from Hagerstown.

Stephen Juan, Ph.D. is an anthropologist at the University of Sydney. Email your Odd Body questions to s.juan@edfac.usyd.edu.au

3 Big data security analytics techniques

More from The Register

next story
Red-faced LOHAN team 'fesses up in blown SPEARS fuse fiasco
Standing in the corner, big pointy 'D' hats
KILLER SPONGES menacing California coastline
Surfers are safe, crustaceans less so
Opportunity selfie: Martian winds have given the spunky ol' rover a spring cleaning
Power levels up 70 per cent as the rover keeps on truckin'
KILLER ROBOTS, DNA TAMPERING and PEEPING CYBORGS: the future looks bright!
Americans optimistic about technology despite being afraid of EVERYTHING
Discovery time for 200m WONDER MATERIALS shaved from 4 MILLENNIA... to 4 years
Alloy, Alloy: Boffins in speed-classification breakthrough
Liftoff! SpaceX Falcon 9 lifts Dragon on third resupply mission to ISS
SpaceX snaps smartly into one-second launch window
Elon Musk's LEAKY THRUSTER gas stalls Space Station supply run
Helium seeps from Falcon 9 first stage, delays new legs for NASA robonaut
prev story

Whitepapers

Securing web applications made simple and scalable
In this whitepaper learn how automated security testing can provide a simple and scalable way to protect your web applications.
3 Big data security analytics techniques
Applying these Big Data security analytics techniques can help you make your business safer by detecting attacks early, before significant damage is done.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Top three mobile application threats
Learn about three of the top mobile application security threats facing businesses today and recommendations on how to mitigate the risk.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.