FI L ED U.S. COURT OF APPEAL S EL EVENTHCI RCUI T APRI L6, 2010 J OHN L EY CL ERK [PUBLIS H] IN THE UN ITED STATES COURT OF APPEALS FOR THE ELE VENTH CIRCUIT

__ __ __ __ __ __ __ __ __ __ __ __ No. 0 9- 11 10 4

__ __ __ __ __ __ __ __ __ __ __ __ D. C. Dock etNos . 07 -1 02 91 -CV-ORL-2 2- DAB,

06 -MD-0 17 69 -ACC- DAB LINDA GUINN, Pl ai nt iff -Ap pe ll an t, ve rs us ASTRAZENECA PHARMACEUTICALS LP, ASTRAZENECA AB, ASTRAZENECA LP, ASTRAZENECA PLC, Defen da nt s- App el le es .

__ __ __ __ __ __ __ __ __ __ __ __ App eal fro m

th e Uni te d S ta te s Di st ric t Co urt fo r th e Mi dd le Dis tri ctof F lo rid a

__ __ __ __ __ __ __ __ __ __ __ __ _ (Ap ril 6, 2 01 0) Befo re DUBINA, Ch ie f Ju dg e, BIRC H andBLACK, Cir cu itJu dg es . PER CURI AM:App el la ntLin daGui nn bro ug htsu itag ai ns t Ap pe ll ee As tra Zen eca

Ph arm aceu ti cal s LP (As tra Zen eca) , cla im in g h er u se of t he pre sc rip ti on dru g Sero qu el cau se d h er t o d ev el op di ab et es . Prio r to tri al , AstraZen eca f il eda Dau be rt m ot io n fo r th e ex cl us io n o f th e ex pe rt t es ti m on y of Dr. J en ni fer M ark s an d am ot io n fo r su m

m ary jud gm en t. Aft er co nduc ti ng a Dau be rt he ari ng , th e di st ric t co urt en te redanord er g ran ti ng bo th m ot io ns . The co urt fo un d t ha t su m m ary jud gm en t i n fa vo r of AstraZen eca wa s ap pr op ria te be cau se Gui nn ha d fai le d t o e st ab li sh a ge nu in e is su e o f m at eri al facton th e is su e o f cau sa ti on . The co urt b as edit s ru li ng on two alt ern at iv e g ro un ds . Fir st , th e co urt h el d tha t the te st im on y of Dr. M ark s, Gu in n’s o nl y ev id en ce o n t he is su e o f sp eci fic cau sa ti on , di d n otsat is fy

th e requi rem en ts of Rul e 7 02 of the Fed eral Ru le s o f Evi de nc e an d th eref or e sh ou ldbe ex cl ud ed . Seco nd , th e d is tri ctco urt h el d t ha t ev enif Dr. Mark s’ tes ti m on y

were ad m is si bl e, itdi d n otsupp ort the co nc lu si on th atitwas m or e li ke ly tha n n otth atSero qu el subs tant ia ll y co ntrib ut edto cau si ng Gui nn ’s di ab et es . W e aff

irm th e d is tri ctco urt’s o rd er g ran ti ng bo th AstraZen eca’s Dau be rt an d s umm ary jud gm en t m ot io ns .

2I. BACKGROUND

A. Pro cedur al His to ry Gui nn bro ug htsu itag ai ns t As tra Zen eca i n t he Dis tri ctof M as sa ch us et ts , cl ai m in g t o h av e d ev el op eddi ab et es as ares ul t o f ta ki ng Sero qu el . Gui nn ass ert ed cl ai m s ag ai ns t As tra Zen eca f orst ric t p ro du ct s l iabi li ty, ne gl ig en ce, fraud , andciv il co ns pi racy. Gui nn co nt en de d t ha t wh il e h er p res cri be rs were u na ware o f an y in crea se d ri skof h y

pe rg lycem iaor d iabe te s as so ci at edwith S ero qu el , AstraZen eca kn ew Sero qu el cau se d wei gh t g ai n i n app ro xi m at el y on e-qua rte r to on e-thi rdof pa ti en ts . Accor di ng to Gui nn , des pi te AstraZen eca’s kno wled ge of t he rel at io ns hi p b etweenSero qu el an d wei gh t g ai n, the co m pa ny m ark et edSero qu el as ha vi ng no effe cton pa ti en ts ’ weig htan d fa il edto in cl ud e ad equa te warn in gs on Sero qu el ’s lab el s as requi redby Uni te d S ta te s Fo odan d Dru g Ad m in is tra ti on (FDA) reg ul at io ns . Gui nn furth er co nt en de d S ero qu el is no m or e eff ect iv e th an ot he r an ti ps y ch ot ic s wh ic h s he cla im s p os e le ss of aris k o f wei gh t g ai n. The Ju di ci al Pan el on Mu lt id is tri ctLit ig at io n t ran sf erre d Gu in n’s ca se an d 91 ot he r act io ns in vo lv in g S ero qu el to th e Mi dd le Dis tri ctof F lo rid a fo r co or di na te d p retria l p ro ceed in gs in Ju ly 200 6. Atth e ti m e o f th e d is tri ctco urt’s su m m ary jud gm en t o rd er, the co ns ol id at edact io n h adgro wn t o i nc lu de th e cl ai m s of sev eral th ou sa ndpl ai nt iff s. 3B. Fact s

Sero qu el , che m ic al ly kno wn as qu et iapi ne fumarate , is anan ti ps y ch ot ic
m ed ic at io n m anuf

actur edan d d is tri bu te d b y AstraZen eca. Se ro qu el ha s b een ap pr ov edby the FDA forus e in th e tr eat m en t o f bi po la r di so rd er an d sc hi zo ph ren ia . Gui nn was p res cri be d S ero qu el fro m May 200 2 t hr ou gh Apri l 20 07 . 1. Dr. Mark s’ Exp ertRep ort Dr. Mark s, Gu in n’s ex pe rt wi tn es s o n s pe ci fic cau sa ti on , firs t g av e h er op in io n i n a n e xp ertrep ort s ub m it te d t o t he di st ric t co urt. Dr. Mark s b eg anhe r 1 di sc us si on of Gu in n wi th a rev ie w of h er m ed ic al reco rd s d at in g b ackto 19 98 . Dr. Mark s n ot edth atth e fi rs t wei gh t s he ha d a va il ab le forGui nn was 1 94 po un ds in Marc h 1 99 9. Acco rd in g t o Dr. M ark s’ rep ort, Gu in n re ach eda pe akweig htof 20 5 p ou nd s i n J anua ry

20 00 an d t he reaf

te r he r wei gh t, tho ug h fl uc tu at in g, ge ne ral ly decre as edun ti l J un e 2 00 2, wh ensh e rea ch edhe r lo wes t wei gh t o f 15 5 po un ds . It was at app ro xi m at el y th is ti m e th atGui nn be ga n t ak in g S ero qu el . Gui nnth enga in edweig htun ti l s he was d ia gn os edwith d iabe te s wi th a weig htof Specific c ausation re fer s to the issue of whethe r the plaintiff ha s demonstrated that the 1 substance a ctually

cause d injury

in her pa rticular c ase. Spec ific ca

usation is often distinguished from g ener al ca

usation, which re fer s to the more g ener al issue of whe ther a substance ha s the potential to cause the plaintiff’s injury . See Knight v. Kirby Inland Marine I nc., 482 F.3d 347, 351 (5th Cir. 2007) (discussingthe distinction between spe cific a nd g ener al ca

usation). 419 8 p ou nd s i n F eb ru ary 20 06 . Dr. Mark s s umm ari zedhe r rev ie w of Gu in n’s

m ed ic al reco rd s b y

st at in g s he ga in edap pr ox im at el y forty pou nd s dur in g h er fi ve y ears of t ak in g S ero qu el . Afte r rev ie win g Gu in n’s wei gh t h is to ry , Dr. Mark s co nc lu de d, “ ba se d o n reas on ab le m ed ic al pro babi li ty[,] th atSero qu el was acau se of [ Gui nn ’s] di ab et es .” Dr. Mark s ex pl ai ne d t ha t “ ex po su re t o am ed ic at io n wh ic h c au se d wei gh t g ai n wor se ne d h er u nd erl y in g i ns ul inres is ta nc e an d l ik el y acce le rat edth e o ns etof di ab et es in su ch a pr ed is po se d i nd iv idua l.” 2. Dr. Mark s’ Depo si ti on an d As tra Zen eca’s Dau be rt Mo ti on InDr. Mark s’ dep os it io n, As tra Zen eca p ro vi de d Dr. M ark s wi th ad di ti on al in fo rm at io n re ga rd in g Gu in n’s m ed ic al hi st ory an d m or e fu ll y

ex am in ed Dr. Mark s’ op in io n o n c au sa ti on gi ve n t hi s n ew in fo rm at io n. Th e ad di ti on al
m ed ic al hi st ory

di sc us se d a t the de po si ti on rev eal edth atGui nnha d a lre ady ha d a nu m be r of ris k fa ct or s fo r di ab et es be fo re s he be ga n t ak in g S ero qu el . Gui nnha d st ru gg le d wi th ob es it y , a si gn ifi can t ri skfact orfor di ab et es , andex pe rie nc ed dr am at ic weig htflu ctua ti on s s in ce h er t een ag e y ears . In fa ct , Gui nn ’s weig ht flu ctua te d b efo re, dur in g, an d a fte r he r us e o f Sero qu el , with h er h ig he streco rd ed

5weig htdurin g e ach pe rio d b ei ng rou gh ly equ iv al en t. Gui nnals o h ada se de nt ary 2 li fes tyle, a p oo r di et , a si gn ifi can t fam il y hi st ory of d iabe te s, h y

pe rte ns io n, hyperl ip id em ia , sch iz op hr en ia , andpre di ab et es , all of wh ic h, i n a dd it io n t o h er ag e of 61 , pu t h er atanin crea se d ri skforde ve lo pi ng di ab et es . Dr. Mark s s ta te d s he was no t awa re o f al l o f Gui nn ’s ris k fa ct or s atth e ti m e sh e wro te he r in it ia l re po rt be cau se sh e h adon ly revi ewedm ed ic al reco rd s p ro vi de d t o h er b y Gui nn ’s at to rn ey s d at in g b ackto 19 98 . 3 At the de po si ti on , Dr. Mark s ex pa nd edonhe r th eo ry of c au sa ti on . She rei te rat edhe r be li ef tha t Se ro qu el cau se d Gu in n’s d iabe te s t hr ou gh th e m ech an is m of weig htga in . Whe n a sk edwhatst ep s s he ha d t ak ento de te rm in e whe th er Sero qu el ha d c au se d Gu in n’s wei gh t g ai n, s he rep li edth atsh e h adco ns id eredon ly th e m ed ic al li te ratur e sh owi ng th atSero qu el cancau se weig htga in an d t he te m po ral pro xi m it y

of Gu in n’s u se of t he m ed ic at io n. Dr. Mark s s ta te d s he ha d
m ad e n o a tt em

ptto qu an ti fy

th e am ou ntof we ig htga in sh e at tri bu te d t o S ero qu el an d h addo ne no th in g t o ru le ou t o th er fac to rs as t he so le cau se of Gu in n’s wei gh t

Guinn’s highest rec orded w eights before , duringand af ter he r use of

Seroquel we re 208, 2 205, and 206, re spectively . As an e x ample of Guinn’s previous we ight f luctuations, she re ported weighing 111 pounds in 1986, 208 pounds in 1994, and 155 pounds in 2002. Dr. Mar ks did not know whether thecopy of Guinn’s medic al re cords pr ovided to her by 3 Guinn’s attorne y s was complete . 6ga in . Dr. Mark s fu rth er ac kn owl ed ge d t ha t Se ro qu el do es no t caus e wei gh t g ai n i n

ap pr ox im at el y

two -th ird s o f th e p at ie nt s wh o t ak e th e dru g. Whe n a sk edwhatsh e h addo ne to rul e o utGui nn ’s ot he r ri skfact or s as th e so le cau se of Gu in n’s d iabe te s, Dr. Ma rk s s ta te d s he kn ew of no m etho do lo gy for ru li ng ou t al te rn at iv e cau se s an d t hu s h adno t at te m pt edto do so . In f

act , Dr. Marks ag reedGui nn ’s ot he r ri skfact or s al on e were s uf fic ie ntto ex pl ai n t he on se t of he r di ab et es . Dr. Mark s s ta te d, h owe ve r, sh e h ad“ no way of rul in g o utth e Sero qu el an y

m or e th an[sh e] c[ou ld ] ru le ou t an y ot he r ri skfact or s.” Dr. Mark s al so st at edsh e co ul d n otrul e o utth e p os si bi li ty tha t Gu in n h ad di ab et es be fo re ev er t ak in g S ero qu el . Acco rd in g t o Dr. M ark s, the de ve lo pm en t o f di ab et es is a sl ow, i nc rem en ta l p ro ces s t ha t o ccu rs gra du al ly ove r m any y ears . Dr. Marks ex pl ai ne d t ha t ab ou t h al f of th e p at ie nt s wh o are d ia gn os edwith d iabe te s ha ve actua ll y

ha d t he di se as e fo r ap pr ox im at el y fiv e y ears pri orto di ag no si s. Dr. Marks st at edth atalt ho ug h t he re was so m e ev id en ce i nd ic at in g Gu in n m ay ha ve ha d d iabe te s b efo re t ak in g S ero qu el , sh e b el ie ve d t he ev id en ce was ul ti m at el y in co nc lu si ve . 4

Dr. Mar ks expl ained that Guinn ha d two g lucose re ading s shortly befor e she be g an 4 takingSeroquel that we re a bove the thre shold for a dia gnosis of diabetes. The se re ading s, howeve r, we re unr eliable be cause they wer e take n duringcirc umstances that c ould have ske wed the re sults. Dr. Mar

ks stated that, if she ha d been Guinn’s phy sician, she would have conduc ted follow-up testingto determine whether Guinn had diabe tes at that time. 7Ast raZen eca f il eda Dau be rt m ot io n s eek in g t o e xc lu de Dr. Mark s’ te st im on y ba se d p rimaril y

on st at em en ts m ad e atDr. Mark s’ dep os it io n. Ast raZen eca f

irs t ar gu edth atDr. Mark s h adfai le d t o a de qu at el y co ns id er an d ru le ou t o th er p ot en ti al cau se s o f Gui nn ’s di ab et es . Astr aZen eca f urth er co nt en de d t ha t Dr. Mark s’ m etho do lo gy was unr el iabl e b ecau se itwas b as edpri m ari ly on the te m po ral pro xi m it y

of Gu in n’s i ng es ti on of S ero qu el to he r di ag no si s o f di ab et es . 3. Dr. Mark s’ Decla rat io n So on aft er As tra Zen eca f il edit s Dau be rt m ot io n, Dr. Ma rk s s ub m it te d a de cl arat io n t o s up pl em en t h er i ni ti al ex pe rt r ep ort. Dr. Marks ex pl ai ne d t ha t al th ou gh sh e h adrece iv edad di ti on al m ed ic al reco rd s an d d at a reg ard in g Gu in n si nc e h er i ni ti al rep ort, i nc lu di ng in fo rm at io n p ro vi de d t o h er dur in g h er de po si ti on , “ [t]he ad di ti on al reco rd s p ro du cedd[i d] no t s ub st an ti al ly alte r [h er] co nc lu si on s.” Lik el y in res po ns e to AstraZen eca’s c rit ic is m s, Dr. Ma rk s’ dec la rat io n pr ov id eda m or e co m

pl et e ex pl an at io n o f he r m etho do lo gy. Dr. Mark s ex pl ai ne d th atsh e b as edhe r co nc lu si on on : th e to ta li ty of th e ev id en ce[,] in cl u d i n g th e te m po ral as so ci at io n of in ge st io n of Sero qu el with th e on se t of d i ab e t e s, a st ab le ris k fact or pr of il e witho ut th e di ag no si s of di ab e t e s p r i or to us e of Sero qu el , cl in ic al ev id en ce o f a pa tt ern of ov eral l weig ht ga in whi le onSero qu el pr io r to di ag no si s of di ab et es , . . . ev id en ce of a si gn ifi can tl y in crea se d 8ris k of di ab et es as a res u lt of Sero qu el in ge st io n rep orte d in th e pe errev ie wed li te ratur e, an d th e co ns is te nc y in th e cl in ic al pr es en ta ti on s of [Gu in n] co m

pared with th os e of pa ti en ts in li te ratur e an d cl in ic al tri al s. Dr. Mark s al so rei te rat edth at“ it[was ] no t p os si bl e o r pr act ic al to qu an ti fy th e ri sk of each ris k fa ct or

in each in di vi du al pl ai nt iff .” 4. The Dau be rt Heari ng Dr. Mark s’ th eo ry

of c au sa ti on was m or e fu ll y expl or edin a Dau be rt he ari ng co nduc te d b efo re the di st ric t co urt. Ondi rectex am in at io n, Dr. Ma rk s ag ai n s ta te d t ha t s he ha d c on si de redall of Gu in n’s ri skfact or s fo r di ab et es bu t tha t th ere was no sci en ti fic way to de te rm in e whe th er o ne of t he ris k fa ct or s m ay ha ve be enth e so le cau se of h er d iabe te s. Dr. Ma rk s, h owe ve r, di d n otelabo rat e o n h ow sh e h adco ns id eredGui nn ’s ot he r ri skfact or s i n fo rm in g h er o pi ni on th atSero qu el subs ta nt ia ll y

co nt rib ut edto Gui nn ’s di ab et es . Ins te ad , sh e te st ifi edth at“ [a]ll th e [ri sk ] fact or s wo rkto ge th er.” On cr os s ex am in at io n, Dr. Mark s ac kn owl ed ge d t ha t Gu in n’s o th er ri sk fact or s wer e su ffi ci en t t o e xp la in th e o ns etof h er d iabe te s. In f act , Dr. Mark s 5 te st ifi edth at , gi ve n Gu in n’s ri skpro fil e, itwas “ ve ry li ke ly tha t s he wou ldde ve lo p type II d iabe te s wh ethe r sh e to okSero qu el or n ot .”
Dr. Mar ks also acknow ledg ed, as she had stated e arlier in her de position, that Guinn 5 may have ha d diabetes be fore ever takingSeroquel. Dr. Mar ks’ deposition was admitted into evidenc e at the Daubert hearing a nd used by

AstraZ enec a duringcross e x amination. 9Dr. Mark s al so ackno wled ge d o n c ro ss ex am in at io n t ha t s pe ci fic ev en ts in

Gui nn ’s li fe co ul d h av e cau se d Gu in n t o g ai n wei gh t dur in g t he ti m e sh e to ok Sero qu el . Prio r to tak in g S ero qu el , Gui nn ha d l os t a s ig ni fic an t am ou ntof we ig ht du e to a la ckof app et it e as so ci at edwith ape rio d o f m en ta l i ll ne ss . Dr. Mark s ex pl ai ne d t ha t s he ha d n otbe enaware o f th is cau se of Gu in n’s wei gh t l os s atth e ti m e sh e in it ia ll y

form edhe r op in io n. Dr. Ma rk s ac kn owl ed ge d t ha t as Sero qu el im pr ov edGui nn ’s m en ta l co nd it io n, Gu in n re ve rte d t o h er o rd in ary eat in g h ab it s, whi ch , com

bi ne d wi th he r se de nt ary li fes tyle, were al on e su ffi ci en t t o e xp la in Gui nn ’s weig htga in . Mor eo ve r, du rin g the ti m e Gui nn was t ak in g S ero qu el , sh e ga in edap pr ox im at el y

ten po un ds in th e si x m on th s af te r sh e qui t s m ok in g, so m ethi ng Dr. Mark s s ta te d i s a kno wn caus e o f wei gh t g ai n. Gui nn als o h adtwo se rio us ba ckin

juri es du rin g t he ti m e sh e to okSero qu el , requi rin g s te ro id in jecti on s an d s ur ge ry . Dr. Mark s ac kn owl ed ge d t ha t h er fa il ur e to in cl ud e Gui nn ’s in

juri es in he r rep ort “ was anov ers ig ht ” an d t ha t Gu in n’s i nju rie s an d co ns eque ntreco ve ry

ti m e co ul d h av e co nt rib ut edto he r wei gh t g ai n. Dr. Mark s ag ai n s ta te d o n c ro ss ex am in at io n t ha t s he ha d n otatt em pt ed ei th er t o qua nt ify the am ou ntof Gu in n’s wei gh t g ai n t ha t co ul d b e at tri bu te d t o Sero qu el or t o ru le ou t o th er fa ct or s as th e so le cau se of Gu in n’s wei gh t g ai n. Whe n Dr. M ark s was ask edif s he ha d u se d a ny m etho do lo gy to d et erm in e whe th er 10Gui nn ’s weig htga in whi le on Sero qu el was c au se d b y th e m ed ic at io n ra th er tha n no rm al weig htflu ctua ti on s, Dr. Ma rk s o nc e ag ai n re pl ie d s he kn ew “ of no m etho d to pro ve th atSero qu el cau se d the weig htga in .” Dr. Mark s al so st at edth at al th ou gh sh e o rd in ari ly w ou ldhave a de ta il edco nv ers at io n wi th a pa ti en t reg ard in g i ss ue s s uc h a s d ie t an d e xe rci se to de te rm in e th e cau se of apa ti en t’s weig htga in , sh e d idno t p ers on al ly exam in e o r sp eakwith Gu in n wh enform in g he r op in io n. C. The Dis tri ctCo urt’s Ord er Afte r th e Dau be rt he ari ng , th e d is tri ctco urt en te redanord er g ran ti ng su m m ary jud gm en t i n fa vo r of AstraZen eca. Th e co urt h el d Gu in n h adfai le d t o es tabl is h age nu in e is su e o f m at eri al factonth e is su e o f sp eci fic cau sa ti on ba se d on two sep arat e g ro un ds . Fi rs t, the di st ric t co urt g ran te d s umm ary jud gm en t o n t he ba si s o f it s ex cl us io n o f Dr. Marks ’ te st im on y , Gui nn ’s on ly evi de nc e o n t he is su e o f sp eci fic cau sa ti on . The co urt h el d t ha t Dr. Mark s fa il edto sat is fy th e rel iabi li ty requi rem en t o f Fed eral Ru le of Ev id en ce 7 02 , as e lu ci da te d i n Dau be rt v. Merr el l DowPha rma ceu ti ca ls , Inc ., 50 9 U.S. 5 79 , 11 3 S . Ct. 2 78 6 (1 99 3) . The d is tri ct co urt s ta te d “ Dr. Mark s was un ab le to art ic ul at e an y sci en ti fic m etho do lo gy for as se ss in g wh ethe r, an d t o wh atex te nt , Sero qu el co nt rib ut edto Gui nn ’s weig ht 11ga in an d d iabe te s.” Gui nn v. Astra Zen eca Pha rm. LP, 59 8 F . Sup p. 2 d 1 23 9, 1 24 3

(M.D. Fl a. 20 09 ). The c ou rt a ls o fo un d t ha t Dr. Ma rk s’ op in io n o n c au sa ti on

“ am ou nt s t o n ot hi ng m or e th anin adm is si bl e ip se di xi t , as ‘th e o nl y

co nn ect io n be twee n the co nc lu si on an d t he ex is ti ng da tais th e ex pe rt’s o wn as se rti on s.’” Id
. (quo ti ng McDo wel l v. Br ow n , 39 2 F .3d12 83 , 13 00 (11 th Cir . 20 04 )). The co urt ul ti m at el y

he ldth atex cl ud in g Dr. M ark s’ tes ti m on y was aba si s fo r gr an ti ng su m m ary jud gm en t b ecau se “ Gui nn ha s n o o th er ex pe rt upo n wh os e te st im on y sh e can rel y to est ab li sh sp eci fic cau sa ti on , and‘ th is type o f pr oo f re qu ir es expe rt te st im on y .’ ” Id. at12 43 n.2 5 (q uo ti ng McCl ai n v . Meta bo li fe Int ’l I nc . , 40 1 F .3d 12 33 , 12 37 (11 th Cir . 20 05 )). Seco nd , th e d is tri ctco urt h el d t ha t, ev enif Dr. M ark s’ tes ti m on y was adm is si bl e, he r st at em en ts were i ns uf fic ie ntto est ab li sha ge nu in e is su e o f
m at eri al factwith re sp ectto sp eci fic cau sa ti on . The co urt n ot edDr. Mark s te st ifi edth atfact or s o th er tha n S ero qu el co ul d h av e cau se d Gu in n’s wei gh t g ai n, Gui nn ’s pre -ex is ti ng ris k fa ct or s al on e co ul d h av e cau se d h er d iabe te s, an d Dr. Mark s h adm ad e n o a tt em ptto de te rm in e th e rel at iv e co nt rib ut io n o f th e va rio us po te nt ia l caus es of Gu in n’s wei gh t g ai n anddi ab et es . The d is tri ctco urt he ldth at , gi ve n t hi s t es ti m on y , no reas on ab le juro r co ul d c on cl ud e th atSero qu el
m or e li ke ly tha n n otpl ay eda ro le in cau si ng Gui nn ’s di ab et es . 12II. STANDARD OF REVIEW

Thi s C ou rt r ev ie ws a d is tri ctco urt’s d eci si on reg ard in g t he adm is si bi li ty of ex pe rt t es ti m on y

foranab us e o f di sc ret io n . Uni te d Sta tes v. Fr az ie r , 38 7 F .3d 12 44 , 12 58 (11 th Cir . 20 04 ). W e rev ie w a di st ric t co urt’s g ran t o f su m m ary jud gm en t d e n ov o. Mid

ra sh Se ph ar di, Inc . v. Tow n o

f S ur fs id e , 36 6 F .3d12 14 , 12 22 –2 3 (1 1t h C ir. 2 00 4) . III. DISCUS SION As ex pl ai ne d abo ve , th e d is tri ctco urt b as edit s o rd er g ran ti ng su m m ary jud gm en t o n t wo s ep arat e h ol di ng s. Be cau se alt ern at iv e h ol di ng s ar e acc or de d pr eced en ti al va lu e inth is Cir cu it , Bra vo v. Uni te d Sta tes , 53 2 F .3d11 54 , 11 62 –6 3 (1 1t h C ir 2 00 8) , we wil l ad dr es s ea ch of t he di st ric t co urt’s ru li ng s i n turn. A. The Adm is si bi li ty of Dr. Mark s’ Exp ertTest im on y Ru le 70 2 o f th e Fed eral Ru le s o f Evi de nc e g ov ern s the adm is si on of e xp ert te st im on y . This Cir cu itap pl ie s a t hr ee-p artin qu iry to d et erm in e whe th er an ex pe rt ha s m etth e requi rem en ts of Rul e 7 02 . Fra zi er , 38 7 F .3dat 1 26 0. Un de r th is tes t, a co urt m us t co ns id er wh ethe r: ( 1) th e ex pe rt i s s uf fic ie nt ly qua li fie d t o t es ti fy on th e is su es he in te nd s t o a dd res s; (2) th e ex pe rt’s m etho do lo gy is “ su ffi ci en tl y rel iabl e as de te rm in edby the so rt o f in qu iry m an da te d i n Dau be rt ; an d (3 ) th e te st im on y ass is ts th e tr ie r of

fact , th ro ug h t he ap pl ic at io n o f sc ie nt ifi c, te ch ni cal , or

13sp eci al iz edex pe rti se , to un de rs ta ndth e ev id en ce o r to de te rm in e a fac t i n i ss ue .”

Id
. (ci ti ng Ci tyof

Tu sc al oo sa v. Har cr os Ch ems ., Inc
. , 15 8 F .3d54 8, 5 62 (11 th Ci r. 19 98 )). Neit he r th e d is tri ctco urt n orth e p art ie s i n t hi s ca se di sp ut e th atDr. Mark s is qu al ifi edto tes ti fy

as a n e xp erton di ab et es cau sa ti on . There is als o n o d is pu te th atex pe rt t es ti m on y

reg ard in g t he cau se of Gu in n’s d iabe te s wo ul d a ss is t the tri er of factbe cau se th e te st im on y “ co nc ern s m at te rs th atare b ey on d the un de rs ta nd in g of th e av erag e la y

pe rs on .” Se e id
. at12 62 (ci ti ng Uni te d Sta tes v. Ro uc o , 76 5 F.2 d 9 83 , 99 5 (1 1t h C ir 1 98 5) ). Dr. Mark s’ tes ti m on y is th us adm is si bl e u nd er Ru le 70 2 i f he r m etho do lo gy is s uf fic ie nt ly reli ab le . 1. The Met ho do lo gy of Dif fere nt ia l Di ag no si s On ap pe al , Gui nn co nt en ds Dr. Mark s’ tes ti m on y is rel iabl e b ecau se sh e em pl oyed the sci en ti fic al ly accep te d m etho do lo gy of d iff eren ti al di ag no si s. Diff eren ti al di ag no si s “ is acco m pl is he d b y

de te rm in in g t he po ss ib le cau se s fo r th e pa ti en t’s s ym

pt om s an d t he n e li m in at in g e ach of t he se po te nt ia l caus es un ti l reac hi ng on e th atcan no t b e ru le d o utor d et erm in in g wh ic h o f th os e th atcan no t b e ex cl ud edis th e m os t l ik el y .” W es tb erryv. Gis la ved

GummiAB, 17 8 F .3d25 7, 2 62 (4 th Cir . 19 99 ); see al

so McClai n , 40 1 F .3dat 1 25 2 (d es cri bi ng di ffer en ti al

14di ag no si s as “ a p ro ces s o f id en ti fy in g e xt ern al cau se s b y a pr oc es s o f el im in at io n” ). 6 Altho ug h arel iabl e d iff

eren ti al di ag no si s n eedno t ru le ou t al l p os si bl e al te rn at iv e cau se s, i t m

us t atlea stco ns id er o th er fa ct or s t ha t co ul d h av e b eenth e so le cau se of t he pl ai nt iff’s in jury. As the Fo urth Cir cu itex pl ai ne d i n W es tb erry , a

“ di ffer en ti al di ag no si s t ha t fa il s t o t ak e se rio us acco un t o f othe r po te nt ia l caus es m ay be so lac ki ng th atitcan no t p ro vi de a rel iabl e b as is foranop in io n o n cau sa ti on .” 17 8 F .3dat 2 65 ; se e a ls o In re Pa ol i R.R. Y ar d PCB Li ti

g. , 35 F.3d 71 7, 7 59 (3dCir .19 94 ) (“ [A]t th e co re o f di ffer en ti al di ag no si s i s a r equi rem en t th atex pe rts at l eas t co ns id er al te rn at iv e cau se s—th is alm os t h as to be tru e o f an y te ch ni qu e th attri es to fin d acau se of s om ethi ng .”). As o th er ci rcu it s h av e reco gn iz ed , an e xp ert“ m us t p ro vi de a reas on ab le ex pl an at io n a s t o wh y ‘ he or s he ha s co nc lu de d t ha t [a ny alt ern at iv e cau se su gg es te d b y th e d efen se ] was no t the so le cau se ’” of th e p la in ti ff’s in jury. Best

v. Lo we’s Home Ctr

s., In c. , 56 3 F .3d 17 1, 1 79 (6t h C ir. 2 00 9) (qu ot in g Pao li , 35 F.3dat 7 58 n.2 7) ; se e a ls o La uz on v. Se nc o Pr od

s., In c. , 27 0 F .3d68 1, 6 94 (8t h C ir. 2 00 1) (st at in g a n e xp ertm us t “ be

Tec hnically , differ ential diagnosis refe rs to a method of de terminingwhich of two 6 diseases a patient suffe rs from, whe rea s differ ential etiology is a term used to de scribe the proce ss by

which the c ause of

an injury is determined. F ollowing the tr end among fede ral c ourts, howeve r, we will use the term diffe rential diagnosis to refer to both concepts. See M cClain , 401 F.3d at 1252. 15ab le to ex pl ai n wh y ot he r co nc ei vabl e cau se s ar e ex cl ud ab le ”); W es tb erry, 17 8 F.3 d a t 2 65 (ho ld in g a n e xp ertm us t p ro vi de so m e ex pl an at io n o f why oth er po te nt ia l caus es were n otth e so le cau se ); Ka nn ea nk er il v. Termin ixInt ’l, In c. , 12 8 F.3 d 8 02 , 80 8 (3 d C ir. 1 99 7) (ho ld in g t ha t af te r a d efen da ntid en ti fie s a p laus ib le al te rn at iv e cau se , itis “ ne ces sa ry forth e p la in ti ff's expe rt t o o ffera go od ex pl an at io n a s t o wh y

hi s o r he r co nc lu si on rem ai ns rel iabl e”). Whe n p ro pe rly con du ct ed , di ffer en ti al di ag no si s can b e a rel iabl e m etho do lo gy un de r Dau be rt . Se e Bes t , 56 3 F .3dat 1 78 (“ An o ve rwh el m in g m ajor it y of t he co urts of app eal s . . . hav e h el d t ha t a m ed ic al op in io n o n c au sa ti on ba se d upo n arel iabl e d iff eren ti al di ag no si s i s s uf

fic ie nt ly val idto sat is fy

th e [rel iabi li ty] pro ng of t he Ru le 70 2 i nqui ry .”); W es tb erry, 17 8 F .3dat 2 62 (fi nd in g di ffer en ti al di ag no si s “ ha s wi de sp readacce pt an ce i n t he m ed ic al co m m un it y , has be ensubjec t t o p eer r ev ie w, anddo es no t fr eque nt ly leadto in co rrec t re su lt s” ); Pao li , 35 F.3dat 7 58 (sa m e). Howe ve r, “ anex pe rt d oe s n otest ab li sh th e rel iabi li ty of hi s t ech ni qu es or t he va li di ty of hi s co nc lu si on s s im pl y by clai m in g th athe pe rfo rm eda di ffer en ti al di ag no si s o n apa ti en t.” McCl ai n , 40 1 F .3dat

1612 53 . W e th eref or e m us t ex am in e whe th er Dr. Ma rk s co rrec tl y ap pl ie d t he 7 di ffer en ti al di ag no si s m etho do lo gy. 2. Dr. Mark s’ App li cat io n o f th e Dif fere nt ia l Di ag no si s M etho do lo gy The di stric t co urt d idno t ab us e it s d is cret io n b y fin di ng th atDr. Mark s’ di ffer en ti al di ag no si s was un rel iabl e u nd er Dau be rt be cau se sh e fai le d t o ad equa te ly con si de r po ss ib le alt ern at iv e cau se s o f Gui nn ’s weig htga in an d di ab et es . Dr. Mark s h as pre se nt edtwo po ss ib le way s i n wh ic h s he ha s co ns id ered al te rn at iv e cau se s. Fi rs t, i n h er s up pl em en ta l d ecl arat io n, Dr. Mark s s ta te d s he be li ev edot he r po te nt ia l caus es were n otso le ly resp on si bl e b ecau se Gui nn ha d ga in edweig htan d d ev el op eddi ab et es so on aft er t ak in g S ero qu el when Gui nn ’s ot he r ri skfact or s re m ai ne d c on st an t. Dr. Mark s’ rel ia nc e o n t he tem po ral 8 pr ox im ity of t he in tro du ct io n o f anad di ti on al ris k fa ct or , ho wev er, d oe s n otsat is fy th e requi rem en t tha t a d iff eren ti al di ag no si s co ns id er p os si bl e al te rn at iv e cau se s on th e fac ts of t hi s ca se .

Guinn’s contention that the shortc omings found in Dr . Marks’ a naly sis should go to the 7 weight and cr edibility

of her testimony

rathe r than its admissibili ty since Dr . Marks c onducted a differ ential diagnosis is there fore without merit. At the Daubert hearing, Guinn’s counsel similarly char acte rized Dr. Mar

ks’ conc lusions 8 by stating that Dr. Mar

ks “ruled a ll those other risk fa ctors out as be ing the [sol e] cause of the diabetes on the day

it occurr ed bec ause the y

hadn’t c aused it ea

rlier.” 17Tem

po ral pro xi m ity

is ge ne ral ly nota rel iabl e in di cat orof acau sa l rel at io ns hi p. Th is Cir cu itha s h el d tha t “ [t]he tem po ral co nn ect io n b etween ex po su re t o c he m ic al s an d a n o ns etof s ym pt om s, s ta nd in g a lo ne , is en ti tl edto li tt le weig htin de te rm in in g c au sa ti on .” McClai n , 40 1 F .3dat 1 25 4 (q uo ti ng Moo re v. Ash la nd

Ch em. In c. , 15 1 F .3d26 9, 2 78 (5t h C ir. 1 99 8) ); se e a ls o, e.g ., Bla ck v. Fo od

Lio n, In c. , 17 1 F .3d30 8, 3 13 (5t h C ir. 1 99 9) (ho ld in g t ha t u si ng te m po ral pro xi m it y

to est ab li sh cau sa ti on “ is no t an ex erci se in sci en ti fic lo gi c b ut in th e fal la cy

of p os t-h oc pro pt er-h oc reas on in g, wh ic h i s as un acce pt ab le in sc ie nc e as in law.”) ; Ca rtwr ight v. Home Dep ot

U.S.A., Inc
. , 93 6 F . Sup p. 9 00 , 90 6 (M.D. Fl a. 19 96 ) (“ It i s wel l s et tl edth ata cau sa ti on op in io n b as edso le ly on a te m po ral rel at io ns hi p i s n otde riv edfro m th e sc ie nt ifi c m etho d a ndis th eref or e in su ffi ci en t t o s at is fy

th e requi rem en ts of F ed . R. Evi d. 7 02 .”). Altho ug h t em po ral pr ox im ity m ay co ns ti tu te pro ba ti ve ev id en ce i n c ert ai n c irc um st an ces , se e W es tb erry, 17 8 F .3dat 2 65 , sev eral fact or s m ak e itesp eci al ly unr el iabl e in th is cas e. Fi rs t, the tem

po ral rel at io ns hi p a t i ss ue in th is cas e d oe s n otstro ng ly su gg es t tha t Se ro qu el pl ay eda ro le in cau si ng Gui nn ’s di ab et es . Accor di ng to Dr. Mark s’ tes ti m on y , th e d ev el op m en t o f di ab et es oc curs gra du al ly ove r m an y y ears , andap pr ox im at el y ha lf o f th e p at ie nt s wh o a re d ia gn os edwith d iabe te s

18ha ve actua ll y ha d t he di se as e fo r ab ou t fi ve y ears pri or to di ag no si s. Be cau se Gui nnwas d ia gn os edwith d iabe te s o nl y fou r y ears aft er b eg in ni ng to tak e Sero qu el , th e te m

po ral rel at io ns hi p i n t hi s ca se do es no t p ro vi de st ro ng ev id en ce of cau sa ti on ; i n fa ct , itap pe ars to equa ll y in di cat e th atGui nn m ay

ha ve alr eady de ve lo pe d d iabe te s b efo re ev er t ak in g S ero qu el . Seco nd , Gui nn ’s nu m ero us ot he r ri skfact or s fo r di ab et es m ak e itha rdto dr aw an y in fere nc es fro m

th e te m po ral pro xi m it y

of Gu in n’s wei gh t g ai n t o h er di ag no si s o f di ab et es . Dr. Mark s s ta te s t he se ot he r ri skfact or s wer e li ke ly notth e so le cau se of Gu in n’s d iabe te s b ecau se th ey rem ai ne d c on st an t dur in g t he ti m e sh e to okSero qu el . Dr. Mark s, h owe ve r, do es no t ex pl ai n wh y ha vi ng a st ab le ris k pr of il e m ak es itun li ke ly tha t p reex is ti ng fact or s caus edGui nn ’s di ab et es when su ch fact or s p uthe r atanex tre m el y hi gh ris k fo r di ab et es . Mor eo ve r, on e im po rta ntris k fa ct or

—Gu in n’s ag e—d idno t re m ai n c on st an t. Thi rd , no t o nl y

do Gui nn ’s nu m ero us ris k fa ct or s fo r di ab et es m ak e itha rd to dra w any inf

eren ce re ga rd in g c au sa ti on , bu t the vario us othe r po te nt ia l caus es of Gui nn ’s weig htga in als o m ak e ithardto co nc lu de th atSero qu el ev encau se d Gui nnto ga in weig ht . The rec or d i nd ic at es m an y ot he r ev en ts , in cl ud in g b ack su rg ery, qu it ti ng sm ok in g, re co ve rin g fr om m en ta l i ll ne ss , andno rm al weig ht flu ctua ti on s, m ay

ha ve pl ay eda ro le in Gui nn ’s weig htga in du rin g t he ti m e sh e 19was tak in g S ero qu el . Alth ou gh itwou ldbe un reas on ab le to requi re Dr. Ma rk s t o

co nc lu si ve ly rule ou t al l al te rn at iv e cau se s, s he ha s p ro vi de d n o e xp la na ti onof ho w sh e co nc lu de d t ha t, b as edonreas on ab le m ed ic al pro babi li ty, Sero qu el pl ay ed a ro le inGui nn ’s weig htga in de sp it e th es e o th er p os si bl e ex pl an at io ns . Afte r co ns id eri ng th e n atur e o f th e te m po ral rel at io ns hi p a t i ss ue in th is cas e, we co nc lu de Dr. Mark s d idno t ad equa te ly con si de r po ss ib le alt ern at iv e cau se s s im

pl y by not in g t he tem

po ral pro xi m it y

be twee n Gu in n’s i ng es ti on of Sero qu el an d s ub se qu en t d ev el op m en t o f di ab et es . W e d o n otho ldth ata te m po ral rel at io ns hi p c anne ve r be us edto co ns id er al te rn at iv e cau se s o f a p la in ti ff’s in jury; in st ead , we m erel y

fin d tha t t em

po ral pro xi m ity

is no t s uf fic ie nton th e fac ts of t hi s cas e. Dr. Mark s p ro vi de d asec on d p os si bl e ex pl an at io n o f he r co ns id erat io n o f al te rn at iv e cau se s b y

tes ti fy in g t ha t “ [a]ll th e [ri sk ] fact or s [f ordi ab et es ] work to ge th er.” Here Dr. Mark s ap pe ars to be co nt en di ng th atsi nc e d iabe te s ca n h av e m ul ti pl e co nc urren t caus es , sh e n eedno t an al yze the rol e p la y edby each c au se . An ex pe rt, h owe ve r, can no t m erel y co nc lu de th atall ris k fa ct or s fo r a di se as e are subs tant ia l co nt rib ut in g fa ct or s i n i ts de ve lo pm en t. “ The factth at ex po su re t o [asubs ta nc e] m ay be a ri skfact orfor

[a d is eas e] do es no t m ak e itan actua l caus e si m

pl y be cau se [th e d is eas e] dev el op ed .” Ca no v. Ever es t Mi ne ra ls

20Co rp . , 36 2 F . Sup p. 2 d 8 14 , 84 6 (W.D. Tex. 20 05 ). “ [A]lth ou gh th e d iff eren ti al di ag no si s t ech ni qu e is well acce pt ed. . . [, a fi nd in g] th atall po ss ib le cau se s ar e cau se s d oe s n otap pe ar t o h av e g ai ne d g en eral acce pt an ce i n t he m ed ic al an d sc ie nt ifi c co m

m un it ie s.” Id . Whi le m

ul ti pl e fac to rs canworkto ge th er t o c au se di ab et es , Dr. Mark s was st il l re qu ire d t o p ro vi de so m e an al y si s o f why she co nc lu de d t ha t, m or e li ke ly tha n n ot , Sero qu el subs ta nt ia ll y co nt rib ut edto Gui nn ’s weig htga in an d s uc h wei gh t g ai n was am on g t he fact or s t ha t s ub st an ti al ly co nt rib ut edto he r di ab et es . 3. Dev ia ti on fro m

Sta nd ardDiag no st ic Prac ti ces The rel iabi li ty of Dr. Mark s’ m etho do lo gy is fu rth er ca ll edin to qu es ti on by he r fai lu re t o c on du ctth e st an da rddi ag no st ic tec hn ique s s he no rm al ly use d t o ru le ou t p ot en ti al alt ern at iv e cau se s. Se e Bes t , 56 3 F .3dat 1 79 ; Pao li , 35 F.3dat 7 60 . Dr. Mark s ad m it te d t ha t al th ou gh sh e wou ldno rm al ly con du ctanin te rv ie w to de te rm in e th e cau se of apa ti en t’s wei gh t g ai n, s he ha d o nl y rev ie wedsel ect io ns fro m Gui nn ’s m ed ic al reco rd s p rep aredby her at to rn ey s. No t o nl y do es th is cas t do ub t o n Dr. M ark s’ di ffer en ti al di ag no si s, b utitals o v io la te s a p rimary pu rp os e of Dau be rt : t o e ns ur e th e ex pe rt “ em pl oys in th e co urtro om

th e sa m e le ve l o f in te ll ectua l ri go r th atch arac te riz es th e p ract ic e o f anex pe rt i n the rel ev an t fi el d.” Ku hmo Tir e Co . v. Carmich ae l , 52 6 U.S. 1 37 , 15 2, 1 19 S. Ct. 1 16 7, 1 17 6 (1 99 9) . 214. Co nn ect io n b etweenDr. Mark s’ Con cl us io n a ndth e Fac ts

The di stric t co urt d idno t ab us e it s d is cret io n b y alt ern at iv el y

ho ld in g t ha t, ev enif Dr. M ark s’ di ffer en ti al di ag no si s m etho do lo gy was acc ep tabl e, he r te st im on y was u nr el iabl e b ecau se he r co nc lu si on s wer e n otlo gi cal ly sup po rte d b y th e fac ts of thi s ca se . As th e Supr em e Co urt ex pl ai ne d i n Gen er al Elec tr ic Co mpa nyv. Jo in er , “ no th in g i n e it he r Dau be rt orth e Fed eral Ru le s o f Evi de nc e requi res a di st ric t co urt t o a dm itop in io n e vi de nc e whi ch is co nn ect edto ex is ti ng da taon ly by

th e ip se di

xi t of th e ex pe rt. A co urt m ay

co nc lu de th atth ere i s s im pl y to o g reatanan al yti cal gap b etweenth e d at a an d t he op in io n p ro ffer ed .” 52 2 U.S. 13 6, 1 46 , 11 8 S . Ct. 5 12 , 51 9 (1 99 7) ; se e a ls o Mc Dow el l v. Br ow n , 39 2 F .3d12 83 , 13 01 –0 2 (1 1t h C ir. 2 00 4) (“ [A]n ex pe rt o pi ni on is in adm is si bl e whe n t he on ly co nn ect io n b etweenth e co nc lu si on an d t he ex is ti ng da tais th e ex pe rt’s o wn as se rti on s . . . .”). 9 Inde te rm in in g t ha t the ex is ti ng da tadi d n otsupp ort Dr. Ma rk s’ co nc lu si on s, the di st ric t co urt n ot edDr. Mark s’ tes ti m on y est ab li sh edth e Guinn’s ar gument that the district court e rre d by applying thewrongstate law c ausation 9 standard when excluding D r. Mar ks’ testimony

improperly

conflates Daubert’s reliability require ment with the showingnece ssary to survive summary

judgme nt. See City of Tuscaloosa v. Harc ros Chems., Inc. , 158 F.3d 548, 564–65 ( 11th Cir. 1998) (holding that courts should avoid “the c onfusion and conf

lation of admissibili ty

issues with issues reg ardingthe suffic iency of the plaintiff’s evide nce to survive summary judgme nt”). Unde r Joiner , the fa cts of the c ase must mere ly support the expert’s conc lusions, which may or may not satisfy

the plaintiff’s ultimate burden on c ausation. 22fo ll owi ng fact s: Dr. Mark s kne w of n o m etho d t o d et erm in e whe th er Gu in n’s

weig htga in was due to Sero qu el or n orm al flu ctua ti on s i n wei gh t Gu in n h ad ex pe rie nc edth ro ug ho uthe r li fe; itwas “ ha rdto kn ow fo r su re” wh ethe r th e p oi nt in ti m e Gui nn de ve lo pe d d iabe te s h adan yth in g t o d o wi th Sero qu el ; Gu in n h ad nu m ero us pre -ex is ti ng he al th co nd it io ns th atco ul d h av e cau se d h er wei gh t g ai n; Gui nnha d n um ero us ris k fa ct or s fo r di ab et es ; the se ris k fa ct or s wer e su ffi ci en t t o cau se Gui nn ’s di ab et es ; Dr. Ma rk s h adm ad e n o a tt em ptto qu an ti fy

th e rel at iv e co nt rib ut io n o f Gui nn ’s ris k fa ct or s; an d Gu in n l ik el y wou ldha ve de ve lo pe d di ab et es whet he r orno t s he ev er t oo k S ero qu el . Se e Gui nn , 59 8 F . Sup p. 2 d a t 12 46 –4 7. Gi ve n t hi s ev id en ce, the di st ric t co urt d idno t ab us e it s d is cret io n b y ho ld in g t ha t Dr. Ma rk s’ op in io n was un supp orte d b y th e ev id en ce. On ap pe al , Gui nn ha s i de nt ifi edno ev id en ce o f sp eci fic cau sa ti on ot he r th an Dr. Mark s’ tes ti m on y . The d is tri ctco urt the refo re d idno t err by ho ld in g t ha t the ex cl us io n o f Dr. Marks ’ te st im on y is a ba si s fo r gr an ti ng su m m ary jud gm en t i n fav orof As tra Zen eca. Se e All is on v. McGha n Me di ca l Co rp . , 18 4 F .3d13 00 , 13 04 (11 th Cir . 19 99 ); Hag ge rt y v. Th e Upj oh n C

o. , 95 0 F . Sup p. 1 16 0, 1 16 8 (S.D. Fla . 19 96 ).

23B. Fai lu re o f Dr. Marks ’ Test im on y to Crea te a Genui ne Iss ue of M at eri al Fact Alt ern at iv el y , th e d is tri ctco urt d idno t err by ho ld in g t ha t, ev enif Dr. Mark s’ tes ti m on y

were ad m is si bl e, he r st at em en ts wou ldno t h av e cre at eda ge nu in e is su e o f m at eri al factwith re ga rdto sp eci fic cau sa ti on . Und er Fl or id a la w, a pl ai nt iff

: m us t i nt ro du ce ev id en ce wh ic h a ffo rd s a r eas on ab le ba si s fo r th e co nc lu si on th atitis m or e li ke ly tha n n otth atth e co nduc t o f th e de fen da ntwas asubs ta nt ia l fa ct orin bri ng in g abo utth e res ul t. A m ere p os si bi li ty of su ch cau sa ti on is no t en ou gh ; an d wh enth e m at te r rem ai ns on e o f pu re s pe cu la ti on or c on jectu re, o r th e p ro babi li ti es are atbe stev en ly bal an ced , itbe co m es th e dut y of the co urt t o d ire cta ve rd ic t fo r th e d efen da nt . Goo di ng v. Uni v. Hos

p. Bldg ., Inc
. , 44 5 S o.2 d 1 01 5, 1 01 8 (F la . 19 84 ) (quo ti ng Pro ss er, Law o f Torts § 4 1 (4 th Ed.1 97 1) ); se e a ls o C hr is to ph er v. Cu tt er La bs
. , 53 F.3d11 84 , 11 91 (11 th Cir . 19 95 ) (fu rth er d is cu ss in g t he Flo rid a st an da rdfor pr ov in g c au sa ti on ). The di stric t co urt d idno t err by ho ld in g tha t Dr. Ma rk s’ tes ti m on y am ou nt ed to m ere s pe cu la ti on as t o wh ethe r Sero qu el was asubs tant ia l co nt rib ut in g fa ct orin cau si ng Gui nn ’s di ab et es . Dr. Mark s’ tes ti m on y rev eal s s ev eral fact s t ha t ca st subs ta nt ia l d oubton whet he r Sero qu el co nt rib ut edto Gui nn ’s dev el op m en t o f di ab et es , in cl ud in g t he fol lo win g: app ro xi m at el y two -th ird s o f al l p at ie nt s wh o ta ke Sero qu el do no t ex pe rie nc e wei gh t g ai n; m an y ot he r fac to rs pl au si bl y

co ul d 24ha ve cau se d Gu in n’s wei gh t g ai n; ab ou t h al f of all pa ti en ts ha ve di ab et es fiv e y ears pri orto di ag no si s (wh ic h wo ul d h av e b een be fo re Gu in n b eg antak in g Sero qu el ); Gu in n h adm

ul ti pl e ri skfact or s t ha t co ul d h av e b een th e so le cau se of Gui nn ’s di ab et es ; an d Dr. M ark s was un ab le to de te rm in e th e rel at iv e ri skof e ach fact or . Giv enth es e fac ts , th e d is tri ctco urt d idno t err by ho ld in g t ha t n o reas on ab le juro r co ul d fi ndSero qu el was, m or e li ke ly tha n n ot , a subs ta nt ia l co nt rib ut in g fa ct orin cau si ng Gui nn ’s di ab et es . 1 0 IV. CONCLUSION Fo r th e rea so ns st at edab ov e, we ho ldth e d is tri ctco urt d idno t err by ex cl ud in g Dr. M ark s’ tes ti m on y an d h ol di ng th atGui nn fai le d t o e st ab li sh a ge nu in e is su e o f m at eri al facton th e is su e o f sp eci fic cau sa ti on . W e th eref or e affi rm th e d is tri ctco urt. AFFIRMED.

On appe al, the par

ties dispute whether

Florida law also re quires Guinn to show that but 1 0 for he r ing estion of Seroque l, she would not have de veloped diabe tes. As the district cour t held, howeve r, this issue of Florida law nee d not be addr essed be cause Guinn has fa iled to meet her burden unde r the morelenient substantial contributingfac tor test. 25