Posts Tagged ‘Epidemiologists’

Scientists and Epidemiologists use statistics but that doesn’t mean Epidemiologists are Scientists

June 11, 2017

“Scientists prove Left-handers can predict the future”

10 left-handers and 10 right-handers play “heads or tails”.
Left-handers win 60% of games.
Players say Left-handers have been lucky.
Scientists say there is no proven link.
Statisticians say there is a 0.2 correlation between being left-handed and the ability to foresee the toss of a coin.
Epidemiologists will publish paper claiming that evidence indicates that Left-handers may have degree of prescience.
Newspapers will report the paper with the headline “Scientists prove Left-handers can predict the future”.
On the basis of the report the Epidemiologists are appointed by Minister of Education to design courses to promote Left-handedness amongst school-children.

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Epidemiologists are not Scientists

April 30, 2013

Just skimmed Gov’t paper on alcohol and the basis of the points system.

House of Commons

Science and Technology

Committee

Alcohol guidelines

Eleventh Report of Session 2010–12

Report says it’s based on physiological and epidemiological studies.

References

1 Robinson S & Lader D (2011). Smoking and drinking among adults, 2009: a report on the 2009 General

lifestyle Survey. Newport: Office for National Statistics.

2 Robinson S & Lader D (2011). Smoking and drinking among adults, 2009: a report on the 2009 General

lifestyle Survey. Newport: Office for National Statistics.

3 Robinson S & Lader D (2011). Smoking and drinking among adults, 2009: a report on the 2009 General

lifestyle Survey. Newport: Office for National Statistics.

4 Hasking P, Shortell C & Machalek M (2005). University students’ knowledge of alcoholic drinks and their

perception of alcohol-related harm. Journal of Drug Education 35: 95–109.

5 Gill F & O’May F (2006). How “sensible” is the UK sensible drinking message? Preliminary findings

amongst newly matriculated female university students in Scotland. Journal of Public Health 29: 13–6.

6 Plant MA & Plant ML (2006). Binge Britain: alcohol and the national response. Oxford: Oxford University

Press.

7 Office for National Statistics (2010). Drinking: adults’ behaviour and knowledge in 2009. London: Office for

National Statistics.

8 HM Government (2007). Safe. Sensible. Social: the next steps in the national alcohol strategy. London: The

Stationery Office.

9 Office for National Statistics (2010). Drinking: adults’ behaviour and knowledge in 2009. London: Office for

National Statistics.

10 Office for National Statistics (2010). Drinking: adults’ behaviour and knowledge in 2009. London: Office

for National Statistics.

11 Department of Health (2010). Consultation on options for improving information on the labels of alcoholic

drinks to support consumers to make healthier choices in the UK—response to consultation. London: The

Stationery Office.

12 Babor T, Caetano R, Casswell et al (2003). Alcohol: no ordinary commodity. Oxford: Oxford University

Press.

13 Gray R & Henderson J (2006). Review of the fatal effects of prenatal alcohol exposure. Report to the

Department of Health. Oxford: National Perinatal Epidemiology Unit, University of Oxford.

14 Welch-Carre E (2005). The neurodevelopmental consequences of prenatal alcohol exposure. Advances in

Neonatal Care 5: 217–29

15 Sokol R J, Delaney-Black V & Nordstrom B (2003). Fetal alcohol spectrum disorder. Journal of the

American Medical Association 290: 2996–9.

16 O’leary C M (2004). Feta alcohol syndrome: diagnosis, epidemiology, and developmental outcomes. Journal

of Paediatrics and Child Health 40: 2–7.

17 Royal College of Obstetricians and Gynaecologists (2006). alcohol consumption and the outcomes of

pregnancy, London: Royal College of Obstetricians and Gynaecologists.

18 Gray R & Henderson J (2006). Review of the fatal effects of prenatal alcohol exposure. Report to the

Department of Health. Oxford: National Perinatal Epidemiology Unit, University of Oxford.

19 O’leary C M (2004). Feta alcohol syndrome: diagnosis, epidemiology, and developmental outcomes. Journal

of Paediatrics and Child Health 40: 2–7.

20 Royal College of Obstetricians and Gynaecologists (2006). alcohol consumption and the outcomes of

pregnancy, London: Royal College of Obstetricians and Gynaecologists.

21 Mukherjee R A S, Hollins S, Abou-Saleh M T et al (2005). Low level alcohol consumption and the fetus.

British Medical Journal. 330: 375–6.

cobber Pack: U PL: CWE1 [E] Processed: [03-01-2012 16:32] Job: 015231 Unit: PG03

Ev 82 Science and Technology Committee: Evidence

22 Sood B, Delaney-Black V, Covington C et al (2001). Prenatal alcohol exposure and childhood behaviour at

age six to seven years L I. Dose-response effect. Paediatrics 108: e34

23 Little J F, Hepper P G & Dornan J C (2002). Maternal alcohol consumption during pregnancy and fetal

startle behaviour. Physiology and Behaviour 76: 691–4.

24 Hepper P G, Dornan J C & Little J F (2005). Maternal alcohol consumption during pregnancy may delay

the developmental of spontaneous fetal startle behaviour. Physiology and Behaviour 83: 711–4.

25 Sayal K, Heron J & Golding J (2007). Prenatal alcohol exposure and gender differences in childhood mental

health problems: a longtitudinal population-based study. Paediatrics 119: 426–34.

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Glancing down that list of references I’m seeing a lot of  “Authorative Opinion” and a lot of  Epidemiological evidence.

(Why do the media and politicians consider Epidemiologists to be Scientists? At most, they are capable of a bit of Statistical Analysis)

There is very little obvious physiological evidence used, although the report uses reference (10) to point out that Alcohol has a beneficial effect in terms of easing heart problems and, basically , says that it is helpful for older people, whose risk of cardio-vascular problems is higher.

The graphs below are epidemiological in nature but seem to indicate the benefits of up to four drinks per day for men , or two for women (smaller stature).

 

Viz.

The International Scientific Forum on Alcohol Research and Alcohol in Moderation explained that the J shaped curve shows that light and moderate drinkers of any form of alcohol live longer than those who abstain or drink heavily. The relative risk of mortality is lowest among moderate consumers (at the lowest point of the J), greater among abstainers (on the left-hand side of the J), and much greater still among heavy drinkers (on the right-hand side of the J). In addition to longevity in general, the J-shaped relationship also exists for cardiovascular deaths, specifically for coronary heart disease and ischemic stroke.(49)

j-curve

Unfortunately the problem with epidemiological evidence, even when validated by a known mechanism, is open to contradiction in terms of other factors, which have not been taken into account.

For instance. some of the ”Authorative” opinions propose that alcohol can be a cause of some Cancers (? — Almost everything can be proposed to be carcinogenic)

The report says “The lingering question is whether this association (cardio-vascular protection) is causal. Clearly, observational studies cannot establish causation. However, when the present results are coupled with those from our companion review paper7 summarising intervention mechanistic studies focusing on biomarkers associated with cardiovascular disease, the argument for causation becomes more compelling. Indeed, the mechanistic biomarker review shows biological plausibility for a causal association by showing favourable changes in pathophysiologically relevant molecules.

 

In other words, alcohol probably does afford cardio-vascular protection and the jcurves have some physiological support.

 

No other physiological associations seem to be reported, although I wouldn’t be surprised to find that there is a known physiological mechanism connecting alcohol consumption with Cirrhosis.

Even so most of the evidence is still epidemiological I.e. a slightly more sophisticated version of The French drink a lot of wine and there is a high incidence of Cirrhosis in France.

 

My whinge about all the evidence used, which the recommended alcohol consumption levels are based on, is so nebulous and poorly founded.

Indeed a lot seems to be founded on the prejudices of those in Authority.

Then to compound this mass of supposition and prejudice is the argument that a simplistic set of guidelines are needed, because the Public hasn’t the capacity to digest a more thoughtful set of guidelines.

Then, furthermore, these guidelines have to err on the side of caution. Not all men are of large structure and able to cope with the higher levels of alcohol. The cardio-vascular benefits aren’t a significant benefit for younger fitter men.

The report is aware of how  unscientific its evidence base is and goes to great length’s to justify itself by comparing its guidelines with those set up by other similarly ill-founded guidelines, used in other Nations. Its recommendations, it claims, fall safely (phew!) within the average of these other guidelines. (actually, well towards the more cautious end)

The consequence is that the guidelines come close to warning that anyone imbibing more than a thimbleful of grog is in imminent risk of needing admission to Hospital.

The report is, to my mind, an insult and a waste of Public money. It throws into question the credence to be placed on all such reports

What I need is advice on how much damage can be done to my body by alcohol.

Whether any such damage is irreversible and in what respect. E.g. The dehydrating effect may kill brain cells, so how much would I have to drink before I would be eligible to qualify as a politician? How long would it take?

Most damage will be reversible, so if I drink 10 pints of bitter on a night out (not that I probably could, or would at my age), how long would I need to wait before I could binge again.

Is the rate of recovery such that I could drink  1 pint every day, without any long term problems?

Or is that 2, 3, 4 etc. pints per day.?  if I’m big and fat, can I drink more?

Most importantly, I want the figures based on studies of physiological measurements/mechanisms; not epidemiology analyses and certainly not based on “expert opinion”.  After all, It was “expert opinion” which said that the Earth was at the centre of The Universe.