O'Carroll & Henshaw 2008 Aggregating Disparate Epi Evidence Risk Analysis 28(1)_ 225-234

8/12/2019 O'Carroll & Henshaw 2008 Aggregating Disparate Epi Evidence Risk Analysis 28(1)_ 225-234

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Risk Analysis, Vol. 28, No. 1, 2008 DOI:

10.1111/j.1539-6924.2008.01009.x

Aggregating Disparate Epidemiological Evidence:Comparing Two Seminal EMF Reviews

Michael J. OCarroll!and Denis ". #enshaw

$

Two seminal reviews I!"#$ 2002% #D&'$ 2002( o) *ossi+le ,eal,

e))es )rom*ower- )reen s rea,e*arl i))eren onlsions

)rom similar e*iemioloial eviene. T,ese i))erenes ,ave an im*a

on *reaionar *oli. 7e examine ,e saisial areaion o)

resls )rom inivial is*arae sies. 7i,o onsisen ex*osre

meris$ -,e avanae o) mea-analsis o esimae manie o) e))e

is los. &owever$ onin *osiive an saisiall sini)ian resls

iels im*oran in)ormaion. T,is is no a s+sie )or mea-analsis$

+ a )all-+a w,en meanin)l mea-analsis is no availa+le. "e*resen-aive resls )rom 33 ine*enen al leemia sies a+le + I!"#

iele 23.5*osiives p 0.01( an 9 sini)ian-*osiives p < 10(.

rom 43 re*resenaive resls )rom #D&'$ ,ere were 32 *osiive p oli +ase on ,e ris o) ,il,oo

leemia alone ens o +e limie +ease

,e normal iniene is om*araivel rare

an ,e ari+a+le ris ver small. T,e

esion o) aiional ris o) o,er iseases

,en +eomes im*oran. &ene ,e#ali)ornia review$ + reoniCin )ive ,eal,

oomes orres*onin o ,e 2@ lassi)ia-

ion$ ,allenes ,e limiaion o)

*ro*orionae *reaionar measres o

,ose o) ver low os.


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4OCarroll and #enshaw

!n nersanin o) ,e i))erenes

+eween ,ese seminal reviews is ,ere)ore

im*oran o ,e *resen evelo*men o)

*reaionar*oli )or 4s.

$. T#E T'O SEM()A" EMF

#EA"T# RE,(E'S OF (ARC

A)D CD#S

@o, I!"# 2002( an #D&' 2002(

evalae ,e *ossi+le riss o *+li

,eal, )rom 4s a s**l )reen.

#D&' onsiere onl *ower- )reen

s$ w,ereas I!"# onsiere o,er

)reenies + s*ei)iall assesse *ower

)reen or ?(. I!"# assesse

arinoeni ris w,ereas #D&' assesse

+o, arinoeni an o,er ,eal,

oomes. Gever,eless$ ,e wo reviews ,a

a lare area o) ommon ron in ,e +oo) eviene relain o *ower-)reen

)iels an varios aner oomes.

T,e )ormaive wor )or I!"# 2002( was

arrie o a a 7orin Hro* meein in

ne 2001. T,e #D&' *roram exene

over several ears wi, #onsultation $ra%t &*+lis,e in !*ril 2001. I!"# 2002( i

no re)er o reen #D&' ra)s + i re- )er

o an earlier *roress review Gera et al.$

1996(. T,e )inal re*or o) #D&' 2002(

re)erre o I!"# 2001 in *ress( an

*arilarl aresse ,e esion o) ,eir

i))erin onlsions.

I!"# 2002( lise some 800 re)erenes$

over- in +o, ? mainl *ower-

)reen( an sai )iels. #D&' lise

some 400 re)erenes ? onl(.T,e I!"# lassi)iaion ssem )ormall

om- +ines assessmens o) eviene in

,mans esseniall e*iemiolo( an

eviene in animals. @o, reviews were aree

in assessin ,e eviene in animals as

Einae!uate.F ! *arilar i))il in

relaion o ,il,oo leemia is ,a

animal sies ol +e onsiere

ina**ro*riae +ease ,ere is no animal

moel )or ae lm*,o+lasi leemia$ ,eom- mon leemia *e in ,ilren. @o,

reviews were aree in assessin ,e

eviene in ,mans in relaion o

,il,oo leemia as Elimite,F an ,ene

were le + ,e )ormal lassi)iaion ssem o

-,e overall I!"# 2@ assessmen.

#D&' 2002( ses ano,er )ormal ssem

o) assessmen$ a E!ualitati'e (ayesF

a**roa,$ w,i, is a enral )eare o) ,e

review an an ineresin in- novaion.

&owever$ )or ,e *r*ose o) om*arison$,e also *rovie assessmens on ,e I!"#

lassi- )iaion ssem. T,e )ive ,eal,

oomes ieni)ie + #D&' as ea,

warranin I!"# 2@ lassi)iaion o) s

were ,il,oo leemia$ al leemia$


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al +rain aner$ misarriae$ an

amoro*,i laeral slerosis !?'($ a

)orm o) moor nerone isease.

T,is arile om*ares ,e +ases o)

e*iemioloial eviene in ,e woreviews$ s*ei)iall )or al leemia an

al +rain aner. @o, reviews$ i- rel

or inirel$ onsier seleion an ali

o) sies$ an ,e e*iemioloial ,ol rini

o) ,ane$ +ias$ an on)onin a some

len,. 7e )in ,a ,e more maerial

i))erenes lie in ,eir a*- *roa, o

areaion ra,er ,an in ,e +o o) evi-

ene.

-. STAT(ST(CA"

A..RE.AT(O) OF

D(S/ARATE E,(DE)CE

FROM E/(DEM(O"O.(CA"

ST*D(ES

I is no nsal o )in a rane o)

reasona+l ine*enen e*iemioloial

sies$ ea, wi, is limiaions an

saisiall wea )inins$ + never- ,eless

wi, an overall enen o iniae a*ossi-+le e))e. One wa o) areain ,e

eviene )rom s, sies is + mea-

analsis or *oolin$ w,i, ma +e e)ine in

sli,l i))eren was.

T,is ,as ,e avanae o) esimain ,e

manie o) an e))e an *roviin

on)iene limis )rom ,e areae

eviene. ', esimaes are mos

meanin)l w,en areain on a lie-

)or- lie +asis wi, rear o ex*osre meri$

s*ei)ii o) ases$ relevan s+ses o)*o*laion$ an s me,os.

'omeimes$ ,e eviene is more

is*arae$ so ,a onl limie nm+ers o)

similar sies an +e *oole o ive ver

meanin)l esimaes o)*aram- eers s, as

ris esimaes re*resenin manie o) a

*ossi+le e))e. or exam*le$ in ,e onex

o) $ ,e majori o) sies ,ave +een

onerne wi, ,e e))es o) ex*osre o

manei )iels. '- ies ma varaorin o *e o) ex*osre resienial$

o*aional($ s+ses o) *o*laion

ener$ rae$ ae$ sse*i+ili($ ex*osre

meri or *rox measremen$ *roximi$

jo+ ile$ averae$ *ea($ or ris measre

os raio or sanariCe iniene rae($an so on.

7,ile ain aon o) ,e aveas an

ali- )iaions relain o sini)iane an

,*o,esis esin$ as issse$ )or

exam*le$ in "o,man an Hreenlan$ 1998$

,. 12($ i is never,eless *ossi- +le o

mae some assessmen o) ,e sren, o) a-

reae is*arae eviene. T,is ma +e

se)l in s**orin )ormal assessmen o)eviene$ in om- *arin i))eren

areae ses o) sies$ an in


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om*arin i))eren onlsions rea,e+

review+oies.

@ Eis*araeF we mean eviene ,a

oes no reail s**or meanin)l mea-

analsis. @ im*liaion ,is ma relae o a

+roa nerlin ,*o,- esis$ s, as a lass

o) ex*osres ,ro, varin meris

a))ein +ioloial ssems in i))eren was

amon i))erenl sse*i+le *o*laions

mani)esin in a rane o) ,eal, oomes

s,owin onl wea assoiaions in ,e eneral

*o*laion. In ,is+roa sense Eis*ariF is

no neessaril ,e same as E,e- eroeneiF

as someimes evalae wi,in mea-

analsis. T,e *resen siaion is no so

+roa$ ,e main is*arae )eare+ein la

o) a well-e)ine ommon ex*osre meri$es*eiall )or o*aional ex*osre.

T,e wo reviews ea, aress a rane o)

i))eren ,eal, oomes ,a mi, lea o

om*on ,*o,eses s, as asaion o)

+o, ,il,oo an al leemia or +o,

ae an ,roni($ or al- ernaivel o) one

an no ,e o,er$ + we s,all onsier ,em

more s*ei)iall$ as i ,e reviews. #D&'

i +rie)l aress ,e im*liaions )or one

oome o) )inins )or ano,er$ an ,e

I!"# evalaion srre aresses ,e

arinoenii o) an aen ra-,er ,an

,*o,eses )or s*ei)i oomes$+ nei,er

review )ormlae or examine om- *on

,*o,esesper se.

T,is arile illsraes wo sim*le me,os

o) a- reaion: onin nm+ers o)

*osiive )inins an onin nm+ers o)

saisiall sini)ian-*osiive )inins. T,e

more is*arae ,e sies an )inins

onsiere$ ,e +lner ,e im*lie

,*o,esis$ w,ose neaion is ,e nll

,*o,esis ner examina- ion. or exam*le$

areain +o, resienial an

o*aional sies im*lies a ,*o,esis

,a +o, Eex*osresF are asal ris )aors

)or ,e s*ei)ie isease. T,a is more

emanin ,an a ,oie o) ei- ,er s,ar*er

,*o,esis wi, a more onsisen ex*o- sre.

I is no ,e *r*ose o) ,is arile o*rovie

a )ormal analsis o) s,ar*$ +ln$ an

om*on ,-*o,eses.'ome e*iemioloiss mi, )eel ,a s,

a sim- *le me,o o) areaion is oosim*lisi o onsier an ,a

e*iemiolo ,as lon *roresse -o more

so*,isiae analses. &owever$ s,

sim*lis- i areaion is )namenal

saisiall an *ro- vies ,e sor o)

elemenar es ,a s,ol alwas +e

onsiere *rior o more so*,isiae

analsis$ es*eiall i) i iels an nex*ee

resl.

T,s$ ,ese onin me,os are no a

s+si- e )or mea-analsis or *oolin$ w,enavaila+le$+


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an +e a )all-+a )or w,en ,e are no

availa+le. T,ese are iniaive$ ra-,er ,an

onlsive$ me,- os. Go all o) ,e saisial

in)ormaion is se. 4or exam*le$ ,e varin

siCe o) sies is los in onin *osiiveresls. On ,e o,er ,an$ ,ere is some

im*orane o) i))eren sies w,en ,e are

ine- *enen. #onin sini)ian reslsoes re)le ,e saisial sren, o) ,e

)inins$ ,o, no ,e saisial *ower o)

,e sies$ so i *arl overomes ,e

*ro+lem o) )ailin o isriminae +eween

s- ies o) i))eren siCe an *ower. 7e o

no avoae ,ese me,os as a *anaea$

+ we o ses -,a in ,e a+sene o)

an,in +eer$ ,e s,ol no +e

overlooe. 7,a is sr*risin in ,is

insane is ,a ,ere is a similar nerlin

saisial sren, o) aa in +o, reviews$

*arl o+serve in one + seeminl

overlooe in ,e o,er.

0. .E)ERA" COM/AR(SO) OF

E,(DE)CE 1ASES FOR AD*"T

"E*%EM(A

I!"# selee an a+le resls

inlin os raio O"( or sanariCe

iniene raio 'I"( wi, on)iene

inerval #I( aa )rom 3 33 in- e*enen(

,man e*iemiolo sies )or al

leemia$ an #D&' i so )or 43. &owever$

es*ie ,e reviews;*+liaion in ,e same

ear an es*ie ,e ommon re)erene o

*revios reviews$ ,ese ses o) sies ,a

sr*risin i))erenes. @o, reviews ieni)

resienial an o*aional sies s*ei)io al leemia. I!"#;s 3 inle 6

resienial w,ereas #D&';s 43 onl inle

2 resienial.

T,e 43 sies lise + #D&' are erive

*rin- i*all )rom ,e same re)erene

sore =,ei)es et al.$ 199a(. O) ,e 41

o*aional sies$ 1 are inle in ,e

I!"# a+les )or al leemia$ 18 are no

o) w,i, 5 are$ ,owever$ lise in I!"#;s

re)erenes($ an ,e o,er 6 re)er o similarsies + ,e same a,ors e..$ wi,

i))eren aes($ so ma overla*.

O) ,e 32 o*aional sies onsiere

+ I!"#$ a)er ein 1 ommon an 6

similar sies$ ,ere remain 9 ,a are no

in #D&'. O) ,e 6 resienial sies lise+ I!"# Ta+le 25($ onl 1 'everson 1998(

is lise in ,e #D&' a- +le )or al

leemia. T,e seon resienial s lise

+ #D&' is o) 7er,eimer an ?ee*er$

1982($ w,i, is no in I!"#;s Ta+le 25.

O) ,e 41 o*aional sies lise +

#D&'$ ,ere are wo ses o) mli*le sies

)rom ,e same sore -,ree )rom T,erial

et al. 1994( an wo )rom Tnes et al.

1994(% ,e +i+liora*, liss wo


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Ta2le (. !reaion o) ,e !l ?eemia !?( 'ies #onsiere+#D&' 2002(

#D&'/!? 1 *er '( Go. o) O"s >osiives *-ale )or >osiives 'ini)ian->osiives *-ale )or 'i-

"esienial 2 2 0. 1 0.0

O*aional 4 3 0.0 1 1

10

11

Toal 4 3 0.0 1 11012

One-sie osiives *-ale )or 'i->os

"esienial 4 3 0.06L0.31 2 0.0036#o,or o*aional 4 4 0.0625 2 0.0036

#ase-onrol o*aional 5 4 0.185 2 0.0059

Toal 1 1 0.002L0.01 6 3.6

sini)ian-*osiives an no sini)ian-neaives. T,e

p-vales are 0.34 )or ,e *osiives an 0.11 )or -,e

sini)ian-*osiives. 'eleion o) ,i,-ex*osre re-

sls oes no s+saniall ,ane ,e *ire. T,ese

sies o no ive ,e same in o) messae as ,e

manei )iel resls.

4. COM/AR(SO) OF RE,(E'S FOR AD*"T

1RA() CA)CER

#D&' aain aresses ,e esion o) area-

ion$ iin 32 sies )or al +rain aner in Ta+le

9.1.1 o) ,eir s$ om*risin 29 )or o*aional

an 3 )or resienial ex*osres$ an lisin one re*re-

senaive resl )or ea, s O" or o,er ris mea-

sre$ wi, on)iene limis(. #D&' re)ers o a mea-

analsis + =,ei)es o) ,e 29 o*aional sies

wi, overall O" o) 1.2 95K #I: 1.1L1.3( an o nm-

+ers o) *osiive resls an nm+ers wi, O" a+ove

1.2. #D&' i no on nm+ers o) sini)ian re-sls.

In Ta+le 9.2.2 #D&' inles aiional s-

ies o ,e 32 in Ta+le 9.1.1 + ives on)iene iner-

vals )or onl 5 o) ,em. One s om+ines resien-

ial an o*aional ex*osre$ an one is )or ele-

ri )iels wi, a sini)ian *osiive resl(. 7,ile

#D&' issses ,ese aiional seven sies$ -,e

are no inle in is areaion an mae lile

overall i))erene o i(. Or smmar )or ,e 32 ie

sies is iven in Ta+le I.

7,ile ,ese areaions are no as sron as

,ose )or al leemia$ ,e are ,i,l sini)ian.I!"# seles 38 sies wi, +rain aner resls

)or sein o in is main a+les$ o) w,i, 5 are res-

ienial Ta+le 26($ 15 are o*aional o,or s-

ies Ta+le 29($ an 18 are o*aional ase-onrol

sies Ta+le 30(. T,e res*eive nm+ers o) resls

wi, ris measres an on)iene inervals are 24$

32$ an 53$ ,a is$ 109 in all$ + ,ese inle re*-

eiion o) s+*e resls in oals an inle low-

ex*osre as well as ,i,er-ex*osre resls )rom -,esame sies.

T,ese inle wo sies '*inelli$ 1995% "on-

ne+er et al.$ 1999( ,a are )or ex*osres o sai

manei )iels. T,e wol ,ave +een +eer ex-

le w,en assessin resls )or ? *rini*all

*ower-)reen( )iels$ as ,e wo ex*osres are

ie i))eren. &owever$ ,e #D&' liss also in-

le one o) ,ese sies$ '*inelli 1995($ wi,

resls )or +o, +rain aner *osiive( an )or

leemia neaive(. I!"# inles ,ese *ls -,e

neaive resls )rom "onne+er et al. 1999(. In

reain #D&' an I!"# om*ara+l$ ,ese ina*-

*ro*riae resls are ,ere le) in. T,e e))e is sli,$+

wa o) ilin an overall )inins.

O) ,e 109 re resls$ 1 are *osiive an 16 are

sini)ian-*osiive. T,a wol +e ,i,l sini)i- an

ner a nll ,*o,esis )or a ranom sam*le o)

ine*enen resls. T,ere are also ,ree sini)ian-

neaive resls$ ea, wi, ,e **er on)iene limi

js on 1.0. T,a wol no +e remara+le ner a

nll ,*o,esis )or 109 ine*enen resls p =0.51($ + ol +e ner a sroner alernaive es

,*o,esis wi, a *osiive assoiaion.

One sini)ian-neaive resl is )or a low-

ex*osre aeor resienial s in Ta+le 26% -,a-s is elare )or Enervos ssemF aner ra-,er

,an +rain anerper se+ i is inle in Ta+le 26$

Ta2le (,. !reaion o) 'ies o) !l @rain #aner in #D&' 2002(

#D&'/@rain 1 *er '( Go. o) O"s or "is >osiiv *-ale )or 'ini)ian- *-ale )or 'i-

"esienial 3 2 0 0 1O*aional 2 2 0.0 6 10

5

Toal 3 2 0.0 6 0.00


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14OCarroll and #enshaw

Ta2le ,. !reaion o) 'ies o) !l @rain #aner in I!"# 2002( on ,e @asis o) 'eleion #rieria o Ieni) One "e*resenaive

"esl *er 'I!"#/@rain 1 *er '(Go. o) O"s>osiives

*-ale )or >osiives'ini)ian >osiives

*-ale )or 'i->os

"esienial 5 3 0.5 0 1#o,or o*aional 9 0.15L0.3 3 0.005

#ase-onrol o*aional 0.15 3 0.005

Toal 35

22.

0.04L0.09 6 0.0002

w,i, is )or +rain aner. T,e o,er wo sini)ian-

neaives are in Ta+le 29 an are )or males$ w,ile

,e are aom*anie + nonsini)ian-*osiives )or

)emales% ,e seleion rieria ,ose ,e more *o*-

los males$ ,o, i) males an )emales were om-

+ine ,e sini)iane wol +e los. One sini)ian-*osiive resl was similar + ,e o,er wa ron$

+ein js sini)ian-*osiive )or males alonsie a

nonsini)ian-neaive )or ,e less *o*los )e-

males. 'ome sini)ian-*osiives lise )or #oo et al.

1999( in Ta+le 30 ma loo ss*iios a )irs si,$

as ,ree are re*ore as ,avin O" as 1.2 95K #I

= 1.1L1.2($ w,i, seems o + ol +e

aone )or + ron-o)) )rom$ )or exam*le$

1.1 1.11L1.24( onsisen wi, ,e sal lo-normal

moel.

!**lin or seleion rieria o+ains a more in-

e*enen se o) resls$ a mos one *er s$ al-

,o, as noe a+ove i seles more *o*los male

sies ,a wol +e *arl onere + )emale

sies. One s remaine am+ios an o))ere

alernaive o**osie resls o) )airl eal wei, in

Ta+le 29$ ,e 4loers et al. 1994( s o) enine

rivers or railwa worers )rom ,e 1960s or 190s(% i

was re*resene ,ere as ,al) *osiive an ,al) ne-

aive. T,e resl o) selein one resl *er s is

smmariCe in Ta+le .

! ,is *oin ,e seleion *roess ,as real

weaene ,e areae eviene$ larel +ease so

man sroner resls were in s+ses. T,e selee

eviene remains sini)ian$ i) marinall so$ ans,ol no +e ismisse$ al,o, i wol no ,ave

,e same saisial wei, in assessmen as ,a )or

al leemia. In aiion$ ,e sini)iane o) ,e

nm+er o) sini)ian-*osiive resls is em*ere +

,e exisene o) ,ree marinal sini)ian-neaives

in ,e re aa se$ wo o) w,i, srvive seleion o)

one resl *er s.

!**lin ,e exra se o) seleion rieria loses

even more sren, o) eviene$ as so man o) ,e+rain aner sies o no ,ave an ex*osre as-

sessmen in erms o) )iel sren,. T,e resl$ in

Ta+le I$ ,as now los sini)iane$ +earin in min

,a one sini)ian-neaive resl was also selee.

5. COM/AR(SO) '(T# E,(DE)CE O)

C#("D#OOD "E*%EM(A

T,e same a**roa, o areaion ma +e a*-

*lie o ,e #D&' se o) 19 sies )or ,il,oo

leemia lise in Ta+le 8.1.2. !s wi, o,er ,eal,

oomes$ #D&' a**lies is Esin esF an o+serves

,e 16 *osiive resls o o) 19$ iinp= 0.0004 al-

,o, or mlaive+inomial allaion )or 16 or

more o o) 19 ivesp= 0.002. #D&' oes no on-

sier ,e nm+er o) sini)ian resls 3 o o) 19%p

= 0.01(. T,ere were no sini)ian neaive resls

an no resls )or O" or #?s rnae o 1.00.

I!"# a+les eaile resls )or ,il,oo

leemia )or 14 ,il,oo leemia sies in Ta+les

18$ 19$ an 23$ om*risin 10 resienial ex*osre

sies an 4 relain o se o) omesi a**lianes.

!**lin ,e same *roesses as )or al leemia$

we )in o o) 14 resls one *er s( ,ere are

13 *osiive an 3 sini)ian-*osiive resls$ wi, p-vales o) 0.0009 an 0.005$ res*eivel.

On ,is assessmen o) ,e vale o) ,e lise ses o)

sies$ ,e eviene )or al leemia a**ears

Ta2le ,(. !reaion o) 'ies o) !l @rain #aner in I!"# 2002( on ,e @asis o) 'eleion #rieria o Ieni) "esls wi,

#om*ara+le 2x*osres

I!"# / @rain 'ele "esls( Go. o) O"s >osiives *-ale )or >osiives 'ini)ian >osiives *-ale )or 'i->os

"esienial 5 3 0 0 1#o,or o*aional 4 3 0 2 0.0036

#ase-onrol o*aional 5 3 0 0 1

Toal 1 9 0 2 0.04


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more sini)ian ,an ,a )or ,il,oo leemia.

&owever$ we ,ave no aen ino aon onsis-

en o) ex*osre *e or measremen$ or mani-

e o) a**aren e))e s, as re*resene + O"s.

#D&' re)ers o 7aren+er 2001($ wi, a mea-

anali smmar O" o) 1.3 1.0L1.( )or ,il,ooleemia. T,is mi, reasona+l +e om*are wi,

,e mea-anali smmaries ie )or al leemia

o) 1.2 1.12L1.24( an )or +rain aner o) 1.2 1.1L1.3(

wi, re)erene o =,ei)es et al. 199a(. T,ere is no

m, i))erene+eween all ,ree aner ro*s a-

,is level o) mea-analsis.

T,e wo-*oole analses )or ,il,oo

leemia$ wi, O"s o) 1.69 1.25L2.29( )or ex-

*osres a+ove 0.3 "T + Hreenlan et al. 2000( an

2.00 1.2L3.13( )or ex*osres a+ove 0.4 "T +

!,l+om et al. 2000($ *rovie sroner resls +

)osin on )ewer more o,eren an om*ara+le

sies. !l,o, ,e al leemia an +rainaner sies ma +e more is*arae ,an ,ose

enirel resienial sies *oole )or ,il,oo

leemia$ i wol seem *lasi+le ,a i) ,e ,a

+eer ex*osres measremens ,a ol +e se

)or seleion$ ,e resl wol also +e o sren,en ,e

overall )inin.

6. CO)C"*S(O)S

T,ere is a ris ,a review +oies$ ,owever a-

s$ ma overloo ,e saisial wei, o) are-

ae eviene in a olleion o) is*arae sies,a are iniviall inonlsive. I wol +e ,el*- )l

in im*rovin on)iene in ,eir reviews an as-

sessmen eisions i) ,e isse o) areaion o) is-

*arae eviene ol +e seen o +e aresse ex*li-

il$*re)era+l + a )ormal *oole analsis or mea-

analsis o ive an overall ris esimae$ or i) ,a is no

availa+le$ a leas + ,e sor o) sini)iane analsis

,a we ,ave emonsrae in ,is arile.

In areain eviene + ,e sim*le sini)i-

ane analsis we illsrae$ w,en sin ,e Esin

esF onin nm+ers o) *osiive resls($ os ra-

ios re*ore as rnae a 1.0 or 1.00 e. s,ol+e

one as ,al) *osiive an no isone. #on-

in nm+ers o) sini)ian resls in ,is ase ives

sroner in)ormaion ,an ,e sim*le sin es. I) s-

in ,e mlaive +inomial isri+ion o assess

,e sini)iane o) nm+ers o) *osiive resls or o)

sini)ian-*osiive resls$ i is im*oran ,a ,e in-

ivial resls are ine*enen. 7e ,ave sese a

se o) seleion rieria o *roe a mos one resl

*er s )or ,is *r*ose. &owever$ one isa-

vanae o) ,is a**roa, is ,a a eninel raise

ris in a*arilar aner s+*e ol +eome los in

onsierin all s+*es in one ro*$ )or exam*le all

leukemia$ or all brain cancer.

T,e #D&' ,as aresse ,e areaion o) re-

sls$ sin ,e sin es an re)errin o exernal

mea-anali smmaries$ + i ,as no onsiereons o) sini)ian resls. T,e I!"# review s,ows

no eviene o) ,avin onsiere ,e areaion o)

resls o,er ,an s+jeivel. I ,as onsiere in-

ivial sies in eail an ieni)ie ,eir s,or-

omins$ + ,is ,as le o a enen o )ramen an

ismiss eviene ,a is inrinsiall ,i,l si-

ni)ian.

"eview +oies ,ave a ri, o ismiss eviene on

raional rons$ ain ino aon *oenial+ias$

on)onin$ an me,ooloial limiaions$ as well

as saisial sren,$ + s,ol no o so wi,- o

+ein seen also o ae saisial areaion ino

aon.

T,e #D&' review o))ers a se)l om*lemen-

ar insi, ino ,e wei, o) e*iemioloial evi-

ene in ,man sies. I as a *ers*eive ,a ,e

mainsream inernaional review +oies seem

o ,ave overlooe.

T,e i))erenes in ,e onlsions o) ,e I!"#

an #D&' reviews are no ex*laine+ i))erenes in

,e ses o) sies ,e onsiere. T,eir overla**in

aa ses on al leemia$ w,ile sr*ris- inl

i))eren in ,e sies inle$ +o, re*resen a

,i,l sini)ian +o o) areae eviene. In ,e

ase o) +rain aner$ ,e re ses o) aa +o,a**ear ,i,l sini)ian in areae$ ,o, or se-

leion rieria a**lie o ,e I!"# aa *roe

onl a marinall sini)ian areae resl.

I is e+aa+le w,e,er ,e I!"# lassi)iaion

ssem s,ol +e se o isinis, +eween s*e-

i)i iseases$ sine i seems o +e esine o lassi)

aens. I wol +e reasona+le )or ,e I!"# lassi)i-

aion o re)er o eviene on ,il,oo leemia in

rea,in a 2@ lassi)iaion. T,e aiional eviene

on al leemia an +rain aner mi, ,en a

)r,er s**or$ w,en aen in aiion o ,il,oo

leemia.

@ se*arain ,e eviene in ,mans )or Eall

o,er anersF +esies ,il,oo leemia( an

smmaril lassi)in i as EinaeaeF 'eion 5.5$

*. 338( I!"# ma +e seen as e))eivel *romoin a

,*o,esis ,a s ma +e a ase o) ,il,oo

leemia alone an o) no o,er aners. T,a is ,ow we

see*olimaers iner*rein i. 7e o no ,in ,is is

raional )or om*lex mliasal iseases$ es-*eiall

+earin in min eviene )or *ossi+le ss- emi

e))es ,a ol a))e asaion o) several


16/16

$-0OCarroll and #enshawiseases. I!"# oes no seem o ,ave aresse -,e

esion o) om*on ,*o,eses.

T,is exlsive ari+ion o) ,e I!"# 2@ las-ress ,e im*a o) *ossi+le ,eal, oomes

o,er ,an ,il,oo leemia$ noin es*e- iall ,eir relaivel ,i, iniene om*are

si)iaion o ,il,oo leemia ,as re*erssions in*reaionar *oli$ as mani)es in ,e ra) 7&O

>reaionar 4ramewor 2006(. Owin o is rari$

,il,oo leemia ,as relaivel lile im*a on so-

ie an is avoiane ,ere)ore ,as relaivel lile

+ene)i$ om*are wi, ,e s+saniall more *reva-

len al leemia an +rain aner$ as well as -,e

o,er oomes rae as 2@ + #D&'.

!n earlier review + ,e GI&' 1999( ,a as-

soiae +o, al an ,il,oo leemia wi, a

2@ lassi)iaion$ an +o, ,e I!"# an #D&' re-

views were in)orme+ ,is. Hiven ,e exen an a-

reae sren, o) ,e eviene )or al leemia$

+o, in isel) an in om*arison wi, ,a )or ,il-

,oo leemia$ i is i))il o see a lear ivision ,a

wol s**or an exlsive ,*o,esis o) ar-

inoenii o) s )or ,il,oo leemia + no

)or al leemia.

/ostscript: 'ine or )irs wriin o) ,is arile$

,e s + ?owen,al et al. 200( ,as a**eare$ as

,as or ommenar in ,e same jornal O;#arroll

an &ens,aw$ 200(. T,ese resls rein)ore or on-

lsions in res*e o) al leemia$ ,o, or ar-

men is *rini*all a+o me,oolo.

!7. RECOMME)DAT(O)S

T,e )ollowin reommenaions are mae )or )-

re reviews o) ,eal, e))es.

i( I!"# an o,er review +oies s,ol inor-

*orae ex*ressl ino ,eir me,oolo some

assessmen o) areae vale o) is*arae evi-

ene. ', assessmen s,ol no isel) eer-

mine ,e overall assessmen eision$ + i is

+e--er o +e aware o) ,e nare o) ,e are-

ae aa.

ii( ! )ose *oole analsis s,ol +e ner-

aen )or al leemia o *arallel$ as )ar as

*ossi+le$ ,ose o) !,l+om et al. an Hreenlan

et al. )or ,il,oo leemia.

iii( !visor +oies onsierin *reaionar

*oli relain o s s,ol ae ino a-

on +o, ,e I!"# an #D&' reviews$ in-

lin ,e )ailre o) I!"# o emonsrae

an assessmen o) areae vale o) eviene.

iv( T,e 7&O eam$ in )ormin is >re-

aionar 4ramewor$ s,ol ex*ressl a-

wi, ,il,oo leemia$ an ivin*ari-lar aenion o ,e )ive oomes lassi)ie+

#D&' as orres*onin o I!"# #lass 2@.

AC%)O'"ED.ME)TS

7e ,an #,ilren wi, ?eemia ro-ram$ inal "e*or- ne 2002.

Hreenlan$ '.$ ',e**ar$ !. ".$ =ane$ 7. T.$ >oole$ #.$ M =els,$. !. 2000(. ! *oole analsis o) manei )iels$ wire oesan ,il,oo leaemia.,piemiology$ 11$ 624L634.

I!"#. 2002(. I!"# monora*,s on ,e evalaion o) arino-eni riss o ,mans$ vol. 80$ Gon-ionisin raiaion$ *ar 1:'ai an exremel low )reen ?4( eleri an ma-nei )iels$ I!"# >ress$ 2002.

?owen,al$ ". .$ T$ D. .$ M @ra$ I. #. 200(. "esien- ialex*osre o eleri *ower ransmission lines an ris o)lm*,o*roli)eraive an melo*roli)eraive isorers: ! ase-onrol s.nternal eicine +ournal$ &/$ 614L619.

Gaional Insie o) nvironmenal &eal, 'ienes GI&'(.

1999(. GI&' re*or on ,eal, e))es )rom ex*osre -o*ower-line )reen eleri an manei )iels. GI& >+li-aion Go. 99-4493$ >. O. @ox 12233$ "esear, Trianle >ar$

G#..

O;#arroll$ . .$ M &ens,aw$ D. ?. 200(. ?eer o ,e eior:!l leaemia near *owerlines. nternal eicine +ournal$&/$ 841.

"o,man M Hreenlan. 1998(. oern ,piemiology$ 2n e.>,ilael*,ia$ >!: ?i**ino$ 7illiams M 7ilins.

7&O 4ramewor Hiin >+li &eal, >oli O*ions in !reaso) 'ieni)i arilar "e)erene o 4s.Dra) )or #onslaion$ a 2006. T,e Inernaional 24>roje "aiaion an nvironmenal &eal,

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