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diffetenteet eusclassificat_an in o.r st:dy, we ,wld cveet to f>td
bias elG'Mt aMy froA Or tdYids the plLl ValOe . If . oIl the other
hand . av :u:fferrntial elsclassifiration atfecred onr resolts, the blss
m,ild omly he an attarr.ation of the .stisatn of .effectf far sC :
m:t.inwsly awsord variables as the aras asaessed in this atvdy,
the segtitode of this bias wonid depe :d an the ragnivde of the
correlatian beosn tne tn:e values for etpo .ure aM the valms of
e%PCPre as MWred .
We did not obtain infcmacian On c ertaio variahles km .n to
affaat aa:aw :re . tMStilatim. eisa of coms , pea:imity to the amlmr
a::d other to:ditlons onder M:ieh suklnq taku Plaoe influere the
aocoal doea reeeiwd by the pssiw srolor . Ne atlknwlabge the
diffiwlty in obreirtng d .ta in t.41s raqard, eqacially if irQonation
a6ort a lifetise is tewt souqht . Ma also beleived that askinq for
s :d : ezcee .iw derail in a :, mestiornlre might peeaent our aoqoisitia+
of aar basic irSCCeetlae. Ly distracting the intetvie~ froe
eseentials . Bw t .hese facters say haw influe:ad nur results can not
finally be datw omfned .
Al I o :r omtrols eaee ftm the files of ttr l1n York State
oepareaent of ltwcx velLLclu. M h" .deta to support that they an
caq:eraEle to the msn in tM ooat relew:t ctrraeteriatica . 'Mece
is, h~ . ons potee:tial soorea af pecblv . tt+ereas .e an
CWMia . M. definitioo . thst atl oa.tsols rere lio.n.d drivara, ye do
not kro+ the raxs' staws ,.ithtaqord w dri•Mq . If driving statu+
ls sa:e .tior related to the tisk of 11319 oinoer either directly or . m,ch
.more lue7y, u,C_rly . aor results might haw been soClece to ~ias .
http://legacy.library.ucsf.edu/tid/dsk94c00/pdf
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Na+ewr . !f any poss/ble differences tn drivlrp .eatoa reflect «:ly
differences in aoeioeco :o.te status .our oo:2rol1Ls1 in the analysis
by IHm4E slnuld have taken eaa of the paobls .
Of all the eun¢as aiml to aeaus eqoeore to passive aiWnq .
•me .m .uis,ee: of the apnue achirg hebits has he.n the mst
frequently used . Thia sy .caastt.at least {aftialiy, for tne faez
that Lhis if also t3r a.. .ure .oet otb .: rapccr.d to slew a positive
aaaociatue with luq oncar risk . Iuanq the dUferent wya in MLLCh
spouse smekinq has ber: quantifid, the ms6er of eiqacettr amaroed
p.r day alpa .rs eott often in tlr literature . Nabr of pads a year
xoFed . total nue6er ot ciqatKtss ad:d in a ilfatim, nsEer of
years snddnq, aod mabr of tiqatsttr smlml at haee havw also bm
used n a ptosy for esprs:¢e to passive .nkLg . In the prw :t study
we haw eho.en Mr.e different saars.nrs of eq+oson: 11 :snhr of
eiqarettea saaksd a day by tM al+o:w . 21 :snEar of yaan the srou.e
snoiced. aM 71 total tumber of aiqaettes edud M :ils wmrriad ad
livinq toqetlrr . we pelidvs tiras tlrc.a s.esuraasnts ao :prise
inforn .tim an the t.o snst Utnrtant dlsansio:u of axOmon,
intensity a:d dration. Mditiwly they also prwlde reaolts easily
oaeperabte to those in otMr statiu .
vreviaus studtu have shoun that nae-rid :Lq ..ar: ar-id to
st.ti:ers of 20 or sm cigarettes a day nAlbit a risk of dewlopinq
t•.ng cancer that is aq0eteda+taty double the riak of tlose satritl to
mn-smtrers 125 .17 .301 . The btlsates obtaind in those Kodias hne
bew: :eported to be significant, and .ti.: m:sidezed along virh t!x