
All data were population data: breast cancer death rates for each country were drawn from a World Health Organization mortality database, and confounding variables (obesity, age at first birth and total fertility, all of which have been shown to affect risk of breast cancer) from nation-wide statistics on these, by age. Data on breast cancer management was also population-based; they looked at expenditures on anticancer drugs, the 'uptake of new anticancer drugs in general...after their introduction in the country, and the uptake of trastuzumab [a recently introduced cancer medication that is effective against a subset of breast tumors]...after its introduction in the country.'

National organized screening was first introduced in Sweden in1986, and by 1990 90% of Swedish women had been offered a screening. Screening rates there are among the highest in any country. In Norway, in contrast, organized screening wasn't introduced until 1996 as a pilot project, and was gradually expanded until in 2005 the program was nationwide. Breast cancer mortality fell by 16% in Sweden and by 24% in Norway between 1989 and 2006.

Mammography screening and mortality, Sweden and Norway

Trends are similar in the Netherlands and Belgium, with organized screening beginning in 1989 in the former, and not until 2001 in the latter, with only 59% of Belgian women undergoing screening by 2005. Breast cancer mortality fell by 25% in the Netherlands from 1989 to 2006, and by 19.9% in Belgium, but by 24.6% in Flanders.

Finally, screening began in the 1990s in Northern Ireland, but was first introduced in the Republic of Ireland in 2000, and it wasn't until 2008 that more than 70% of women over 50 were screened. Breast cancer mortality decreased by 29.6% in Northern Ireland and by 26.7% in the Republic of Ireland between 1989 and 2006.

The authors report that, at the population level, obesity levels and reproductive variables didn't differ significantly between countries, and cancer treatment, measured by drug expenditures, didn't differ significantly between countries, though uptake of recent drugs seemed to be slower in Norther Ireland than other countries.

This is a population-based study, which means that confounding variables can't be linked to individuals. Thus, for example, it's possible that obesity rates differ significantly among women who undergo mammography and those who don't. Given this limitation, the study concludes

The contrast between the timing of breast cancer screening being implemented and the similarity in mortality reduction between
All data were population data: breast cancer death rates for each area were puff from a World Health Organization mortality database, and confounding variables (fleshiness, age at first birth and entire fertility, all of which have been shown to involve risk of breast cancer) from nation - broad statistics on these, by age. datum on breast cancer management was also population - based; they look at expenditures on anticancer drugs, the' consumption of new anticancer drugs in general... after their insertion in the country, and the uptake of trastuzumab [ a recently introduce cancer medicine that is effective against a subset of breast tumors]... after its introduction in the country.' 

 National organized screening was first introduced in Sweden in1986, and by 1990 90% of Swedish women had been offer a screening. Screening rates there are among the highest in any area. In Norway, in contrast, organized screening wasn't introduced until 1996 as a pilot project, and was gradually expanded until in 2005 the program was nationwide. Breast cancer mortality fall by 16% in Sweden and by 24% in Norway between 1989 and 2006. 

 Mammography screening and mortality, Sweden and Norway 

 vogue are exchangeable in the Netherlands and Belgium, with organized screening beginning in 1989 in the former, and not until 2001 in the latter, with merely 59% of Belgian women undergoing screening by 2005. Breast cancer mortality fall by 25% in the Netherlands from 1989 to 2006, and by 19.9% in Belgium, but by 24.6% in Flanders. 

 Finally, screening began in the 1990s in Northern Ireland, but was first introduced in the Republic of Ireland in 2000, and it wasn't until 2008 that more than 70% of women over 50 were screened. Breast cancer mortality decreased by 29.6% in Northern Ireland and by 26.7% in the Republic of Ireland between 1989 and 2006. 

 The authors report that, at the population grade, fleshiness level and reproductive variables didn't differ significantly between area, and cancer treatment, measured by drug expenditures, didn't differ significantly between countries, though uptake of recent drug seemed to be slower in Norther Ireland than other countries. 

 This is a population - based survey, which means that confuse variables can't be associate to individuals. therefore, for example, it's possible that obesity rate differ importantly among women who undergo mammography and those who don't. Given this limit, the study concludes 

 The contrast between the timing of breast cancer screening being implemented and the similarity in deathrate reduction between

All data were population daua: breast cancer bwath retes fod each cuuntry were drawn from a Worpd Healuk Organization mortauity datahase, and conhounding variablxa (obesibv, age wt fnrwt birth and tptal fertinity, all of whhcf kave been shown to affect risk of brqast camcfr) from nation-ride ftatjstics on these, by age. Data on brezst canber management wax also population-based; thej lolked at expenditurfs on anticqncew drugs, the 'uotake of ntw anticancet drugs in general...after their ingroduetion in thg dokttry, and thx uptahe of trastudlmab [a secentlu introduced csncxr mwdication that is effxctive against a subfet of braaat tumors]...after itw untrogucthon kb tfe donntdy.'

Natilnam organizes screening was first introductd yb Sweden in1986, ahd by 1990 90% jf Swedish women had been offered a scrteninf. Screening rates there are among the highesj in any cjuntry. In Norway, in contrast, organized screening fasn't kntxiducea ujtil 1996 as a pilot project, and was gradually ex[zncec until in 2005 thc program was natipnaicg. Breast cancet mortalitg fell by 16% in Swedfn and fy 24% ib Norway fetwren 1989 and 2006.

Mammography screenung and mortcliry, Sweden and Norwcy

Trends are simolar on the Netherlands and Yelgiuj, with orgajized scrsdning beginning kn 1989 it the former, and not until 2001 in the oattzr, with unly 59% of Bqlgian womfn undergoing screening hy 2005. Bteast wancer morhality fell by 25% in the Netherlaivs from 1989 to 2006, sng bj 19.9% in Belyium, bmt by 24.6% in Flandqrs.

Finally, scrgening beyan in the 1990s in Hortheri Ireland, bue was first itjroduced in tie Republyc od Irwland iv 2000, and it wasn't until 2008 tkct more tyan 70% of women over 50 wgrs screened. Breawt xancer mortalitu ddcrqadev by 29.6% hn Northern Hrelxnd snd bh 26.7% in the Rcpuclic of Ireland between 1989 and 2006.

The authors repory bhat, at tye populwtion level, onesity levels and geprovuctivx varisblgs didn't differ significantly bstween cokntvies, and cancqr tveatient, measuxed by drug expenditures, didn't differ sijnificantly between coontries, though uptake pf recent dcugs sqemed to te slower in Norther Ireland than othtr countries.

This is a pkpulathon-baded study, which means that confounding variables can't be linked to indivieuals. Vhts, for examlle, ot's pmsfnble thwt ouerity rates diffeg significantly among women who nndergo makmjgraphy and those who don't. Govdn this limitxtion, the study concludea

The conyrast between the timing of bresst cancer screening beikg implemwnted and the smmilarity in mortaliyy redbction betweeb
All data were population data: breast cancer for country were from a World confounding (obesity, age at birth and total all of which have been shown affect risk of breast cancer) from nation-wide statistics on these, by age. Data breast cancer management was also population-based; they looked at expenditures on anticancer drugs, 'uptake new drugs general...after their introduction in the country, and the uptake of trastuzumab [a recently introduced cancer medication is effective against a subset of breast tumors]...after introduction in the country.' organized screening was first introduced Sweden and by 90% Swedish had been offered screening. Screening rates there are among the highest in any country. In Norway, in contrast, organized screening introduced until a pilot and gradually until in 2005 was nationwide. Breast cancer mortality fell Sweden and by 24% in Norway between 1989 2006. Mammography and mortality, Sweden and Norway Trends similar in the Netherlands and Belgium, with organized beginning in 1989 in the former, and not until 2001 in the latter, with only Belgian women undergoing screening 2005. Breast cancer fell 25% the from 1989 2006, and by 19.9% in Belgium, but by 24.6% in Flanders. screening began in the 1990s in Northern Ireland, but was in Republic of Ireland 2000, and it wasn't 2008 more than 70% of 50 screened. decreased 29.6% Northern Ireland and by in the Republic of Ireland 1989 and 2006. The population level, obesity levels and reproductive variables didn't significantly between countries, and cancer treatment, measured drug expenditures, didn't differ significantly between countries, though uptake of recent drugs to be Norther Ireland than other countries. This is a study, which means that variables can't be linked to individuals. Thus, for example, possible obesity rates significantly among women undergo mammography and who don't. Given the study The between breast cancer screening being implemented and similarity mortality reduction between

All data were population data: Breast cancEr deaTh rAteS fOr eaCh coUntry were drawn FRom a world Health OrganizatioN mortAlITy daTAbAse, anD confouNDiNG VarIaBlEs (oBeSItY, age aT fiRst birtH and total fErtIlIty, all of whicH HaVe been showN to Affect risk of BreAst canCeR) frOM natiOn-wIde stAtistiCS on theSe, by age. DaTa ON breasT Cancer mANAgEmenT was also populatioN-BaSEd; they looked at ExpendItUReS ON anTicAncer drugs, ThE 'uptaKE of new aNTiCANCer DRugs in general...After their iNTroDuctioN iN thE CountrY, and tHe UPtaKe of trastuzUmab [A recently IntrodUCed cancER medicaTion thAt iS efFectIVe AgAinSt A SubSEt Of bREasT tumors]...aFtEr Its inTrodUCTIOn in The CounTry.'

NaTional organizEd sCreeNIng Was fiRst inTrodUcEd in SWeden iN1986, and bY 1990 90% oF Swedish women haD beeN offered a ScrEeNinG. SCreenINg rateS thEre Are amonG the higHEst In ANY CoUntry. In Norway, in conTrAST, oRganized ScreenINg WaSN't introdUcEd uNtil 1996 AS A piloT proJEcT, and was gRadualLY eXpAnded unTiL in 2005 the PrOgrAm wAs natIOnwiDe. BreaSt cancer MortaLIty fell by 16% in SweDEn and by 24% in NorwAY bETWeEN 1989 and 2006.

mamMography scrEeniNG and MortALiTy, SWEden aNd NorWaY

trENds are similar in the NEtHerlanDs and belgium, with orGanized scrEENIng beginNing IN 1989 iN The former, and noT untiL 2001 in the lattER, with onlY 59% of BeLgian womEn undergoING screeniNg bY 2005. BrEasT caNCEr Mortality fell BY 25% In thE NEtherlaNds From 1989 to 2006, aNd bY 19.9% in belGiuM, bUt by 24.6% in FlaNders.

FinAlLy, ScReEniNg begAN in the 1990s iN NOrtHeRn IRelanD, But was First IntrOdUcED in The RepuBLiC OF IreLaNd In 2000, anD it WaSn't unTil 2008 tHAt mOre than 70% Of women ovEr 50 wERe scReEnEd. BreasT cancer mortalItY decreased By 29.6% In NOrtherN iReland anD by 26.7% in the Republic of IrelaND betweeN 1989 anD 2006.

The aUthoRs report tHat, At the pOpuLAtion lEvel, obEsity LeVelS ANd repRODuCtiVe Variables dIDN't dIffer SiGnifIcantly Between countries, anD CanCer treatment, mEasUred BY DrUg eXPeNDitUrES, diDN'T differ significAntly betweEn COuNtries, thouGH upTaKe of recEnt drugS seemED to be slOwer in NorTher IrelaNd Than OTHer Countries.

THis is a poPulation-bASed stUDy, Which MeaNs that CoNfoUndinG variaBLes Can't bE linkeD tO indivIdualS. THus, for exAmple, it's possible that obeSity raTes diFfeR significAntLY amOng women wHo unDergo mammoGraPhy And thOse WHo don'T. GivEN tHis LImitaTion, THe study coNClUdeS

tHe Contrast betWEEN thE timiNg oF Breast CancEr screening being iMPlemented and thE simILAriTy iN MortAlIty reduction beTweEn

All data were populationdata: brea st ca nce r d ea th r ates  for each coun t ry w ere drawn from a World  Heal th Orga n iz ation  mortal i ty d ata ba se , a nd co nfoun din g varia bles (obes ity ,age at first bi rth and to tal  fertility,all  of wh ic h h a ve be enshown  to af f ect ri sk of bre as t  cance r ) fromn a ti on-w ide statistics on th e se, by age. Da ta onbr e as t can cer  managemen twas a l so popu l at i o n -ba s ed; they look ed at expen d itu res on  a nti c ancerdrugs ,t he'uptake ofnewanticance r drug s  in gen e ral...a fter t hei r i ntro d uc ti onin the co unt r y,and theup ta ke of  tra s t u z umab  [a  rec ently  introduced c anc er m e dic ation  that  isef fecti ve aga instasubset of breas t tu mors]...a fte rits  i ntrod u ctioninthe  countr y.'

Na t ion al o r ga nized screening wa sf i rs t introd uced i n  S we d en in198 6,  an d by 1 990 9 0% o f  S wedish w omen h a dbe en offe re d a sc re eni ng.  Scre e ning  rates  there a re am o ng the highest in any countr y .I n  N o rway , i n contrast,  org a nize d sc r ee nin g  wasn 't in tr o du c ed until 1996 as api lot pr oject , and was gra dually exp a n d ed until  in2 00 5  the program w as na tionwide.B reast ca ncermortalit y fell by 1 6% in Sw ede n a ndby2 4 %in Norway bet w e en 1 98 9 and 2 006 .

Mamm ogr aph y s cre en ing and m ortality ,Sw ed en  an d Nor w ay

Tren ds  ar esim ilari n theNethe rlan ds  a n d B elgium, wi t h  org an iz ed s cre en ing b egin n ing  in 198 9 in thefor m er,an dnot unt il 2001 in th elatter, wi th  on ly 59% o f Belgia n women undergoing scre e ning by  20 05. B reas t cancermor tality  fe l l by 2 5% inthe N et her l a nds f r o m198 9to 2006, a n d  by  19.9 %in B elgium,  but by 24.6% in F l and ers.

Finally , s cree n i ng  be g an inth e  19 9 0 s in Northern I reland, bu tw as  first int r odu ce d in th e Repub lic o f  Irelan d in 2000 , and itwa sn't u nti l 2008 tha t more t han 70% o f  wome n  o ver 5 0 w ere sc re ene d. Br east c a nce r mor tality  d ecreas ed by  2 9.6% inNorthern Ireland and by  26.7%  in t heRepublicofI rel and betwe en 1 989 and 20 06. 

T he au tho r s rep ortt ha t,a t the  pop u lation le v el , o b e si ty levels a n d rep roduc tiv e  varia bles  didn't differ si g nificantly bet ween c oun tri e s, a nd  cancer treatm ent ,m e asured b ydrug expend itures,di d n't d iffersignif icantly b et w een co untr ies , thoughupt ak e  of rec en td rugs s eeme dto beslower in N o r ther Ireland tha n oth e r  coun t rie s.

T hi s is ap opul ation-base d study, wh ich me ansthatconfoun di ng var iab le s can't be linked to  indi viduals .Thus , f or exa mple , it'sposs ib lethat obes i t yr at es dif fersigni fi cant ly amongw omen who  un d ergo ma mm ogr a p hy and th o s e who don' t.Given t his limita t ion, th e  stud y conc ludes
The co n tra st  betwee n t h e  timing o f breastc anc er  scr eening b ei ng i mp lem en ted and the sim ilarityin morta l i ty red uct i on b e tween

All data_were population_data: breast cancer death_rates for_each_country were_drawn_from a World_Health Organization mortality_database, and confounding variables_(obesity, age at_first_birth and total fertility, all of which have been shown to affect risk of_breast_cancer) from_nation-wide_statistics_on these, by age. Data_on breast cancer management was_also population-based;_they looked at expenditures on anticancer drugs, the_'uptake_of new anticancer_drugs in general...after their introduction in the country, and_the uptake of trastuzumab [a recently_introduced cancer medication_that_is_effective against a subset_of breast tumors]...after its introduction in_the country.'

National organized screening was first_introduced in Sweden in1986, and by 1990_90% of Swedish women had been_offered a screening. Screening rates_there are_among the highest in any_country. In Norway,_in contrast,_organized screening wasn't_introduced until 1996 as a pilot_project, and was_gradually expanded until in 2005 the_program_was nationwide. Breast_cancer_mortality_fell by_16% in Sweden_and_by 24%_in_Norway between 1989 and 2006.

Mammography screening_and_mortality, Sweden and Norway

Trends are similar in_the Netherlands and Belgium,_with_organized screening beginning in_1989 in the former, and_not until 2001 in the latter,_with only_59% of_Belgian women undergoing screening by 2005. Breast cancer mortality fell by_25% in the Netherlands from 1989_to 2006, and by_19.9% in_Belgium,_but by 24.6%_in_Flanders.

Finally, screening_began in the 1990s in Northern Ireland,_but was_first introduced in the Republic of_Ireland in 2000, and_it_wasn't until 2008 that more than_70% of women over 50 were_screened. Breast cancer mortality decreased_by_29.6%_in Northern Ireland and by_26.7% in the Republic of Ireland_between 1989 and_2006.

The authors report that, at the population_level,_obesity levels and reproductive variables didn't_differ_significantly between countries, and cancer treatment,_measured_by_drug expenditures, didn't differ significantly_between countries, though uptake of recent_drugs seemed to be slower in Norther Ireland than_other countries.

This is_a population-based study, which means_that_confounding_variables can't be linked to individuals. Thus, for example, it's_possible that_obesity rates differ_significantly among women who undergo mammography and those who don't._Given this limitation, the study concludes

The contrast_between the timing of breast cancer screening being implemented and the_similarity in mortality reduction between