 weighting algorithm, and they rightfully claimed that such arbitrariness was justified because "there is little empiric [sic] evidence on the relative importance of the individual quality criteria to the control of systematic bias."12 Medical scientists have no principled foundation for developing a uniquely good QAT, and so resort to a relatively arbitrary basis for their development. One could press the standard objection by noting that while it is true that we presently lack an inductive theory that could provide warrant for a unique system for weighting the various methodological features, it is overly pessimistic to think that we will never have a principled basis for identifying a uniquely best weighting system. It is plausible, this objection goes, to think that someday we will have a uniquely best QAT, or perhaps uniquely best QATs for particular kinds of epistemic scenarios, and we could thereby achieve agreement regarding the strength of evidence from medical studies. To this one would have to forgive those medical scientists, dissatisfied with this response, who are concerned with assessing evidence today. But there is another, deeper reason why such a response is not compelling. 12 There is a tendency among medical scientists to suppose that the relative importance of various methodological features is merely an empirical matter. One need not entirely sympathize with such methodological naturalism to agree with the point expressed by Cho and Bero here: we lack reasons to prefer one weighting of methodological features over another, regardless of whether one thinks of these reasons as empirical or principled. 19 It is not a mere argument from present disagreement-I reiterate-to claim that the poor inter-tool reliability of QATs implies that the strength of evidence from particular medical studies is underdetermined. That is because, as the example of the Cho and Bero QAT suggests, the disagreements between QATs are due to arbitrary differences in how the particular methodological features are weighed in the various QATs. There are, to be sure, better and worse QATs. But that is about as good as one can do when it comes to distinguishing between QATs. Of those that account for the majority of relevant methodological features, some weight those features in a slightly different manner than others, and we have no principled grounds for preferring one weighting over another. We do not possess a theory of scientific inference that could help determine the weights of the methodological features in QATs. If one really wanted to, one could sustain the objection by claiming that it is possible that in the future we will develop a theory of inference which would
weighting algorithm, and they rightfully claimed that such arbitrariness was justified because " there be short empiric [ sic ] evidence on the relative importance of the individual quality criterion to the control of systematic diagonal. "12 Medical scientists have no principled basis for developing a uniquely good kat, and so resort to a relatively arbitrary basis for their development. One could bid the standard objection by noting that while it is true that we presently lack an inductive hypothesis that could provide warrant for a unique organization for weighting the various methodological feature of speech, it is overly pessimistic to remember that we will never have a principled basis for identifying a uniquely best weighting arrangement. It is plausible, this objection goes, to think that someday we will have a uniquely best QAT, or perhaps uniquely best QATs for particular kinds of epistemic scenarios, and we could thereby achieve agreement regarding the strength of evidence from medical studies. To this one would have to forgive those aesculapian scientist, dissatisfied with this response, who are concerned with tax evidence today. But there is another, deeper reason why such a reception is not compelling. 12 There is a tendency among medical scientists to presuppose that the relative importance of various methodological features is merely an empirical matter. One need not entirely commiserate with such methodological naturalism to agree with the point expressed by Cho and Bero here: we lack reasons to prefer one weighting of methodological feature of speech over another, regardless of whether one thinks of these reasons as empirical or principled. 19 It is not a mere argument from present discrepancy - I reiterate - to claim that the poor inter - tool reliability of QATs implies that the strength of evidence from particular medical studies is underdetermined. That is because, as the example of the Cho and Bero QAT suggests, the discrepancy between QATs are due to arbitrary difference in how the particular methodological feature are weighed in the assorted QATs. There be, to be sure, better and worse QATs. But that is about equally good as one can do when it comes to spot between QATs. Of those that account for the majority of relevant methodological features, some weight those features in a slightly unlike manner than others, and we have no principled grounds for prefer one weighting over another. We do not possess a theory of scientific inference that could help determine the weights of the methodological features in QATs. If one very wanted to, one could sustain the objection by claiming that it is possible that in the future we will develop a hypothesis of inference which would
 welghting algorithm, and thty rightfully clanned thet such arbitrafiness was justified because "tyere us little empiric [sic] dvidence ln the rwlatmve importance oh the individuzp quclmty criteria to the contrml of systemathc bnas."12 Medical scientists have no princypled fpujdation for dedelokind a hniquely good QAT, and so resort to a relauively arbitrary bssis for their development. One could press the shandard objgdtijb by noting ghat while it is true jhat we presently lack an inductkve tkeory that xoyld krovide warrent fog a unique system for weightong the varioux mxthoeological features, it is overly pessimiftic to tviuk that we will never hqve a pritcipuwd casjs fkr idejtihying a unisuely best qeighting system. It if plausible, thjs objqceion goes, to think that someday we will habe a uniquely best QAT, ir perhaps uniquely bgst QATs fjr particular kinds of epistemic scenarios, and we coulv ghexcny azyifve agreement regarding the strength of evidegde fgom medical studics. To this one woukd hsde to forgive those mesical scientists, dlssatissied qith this reslonse, who are concerned wity assessing vvidwnce today. But thexe is anothex, deepgr reaxon why such a response is hot compelllng. 12 Thers is a tendency aoonn madical scientists to suppofe that tie rekative kmpottance jf various methodological features is mgrely dn empiricwl matter. One need not entirely sympathize wijh vucv methodjlogigal naturalism eo agree with jhe point exprdssed by Cgo and Uero here: we lack reasons jo prefer one weightigg od merhodoloekcal features pver anotktr, regardlwss of whether one thkhks of these recrins as empiricak of pwijcmpled. 19 It is not a merd afbumeng from kxescnt dissgreement-I reiterate-do cmaim that the poor ikter-tool teliabiliey of QATs imllies that the strtngth mf xvidenve srom particular medical studiea is undegdebermined. That is necaose, as the zxample of the Cho and Bero QAT suggests, the disagreements between QATs are doe uo arbitrary vifferqnces in vow the particular mwthodological feauures are weighed in ths varimus QWTs. There are, to be sure, better and worse QATs. But that is about as good qs one can do when it vomes tj distigguidiing between QATs. Of those that account for the oajority oy relevant methodological feayufes, some weigft those features in a smightly cifferent manner than others, anc we have no principled nrounds fir prsferring oie weighting over anpther. Ce do bot poswess a theory of rcirnbific infegenct thct could help determine the weighrs of rhf methodological features ik DATs. Pf one teally wanted to, kne dluld rustain the onjection by clsiming that it is povsyble that in tyv future we woll dgrvlop a theory of inferenwe which would
weighting algorithm, and they rightfully claimed that was because "there little empiric [sic] of individual quality criteria the control of bias."12 Medical scientists have no principled for developing a uniquely good QAT, and so resort to a relatively arbitrary for their development. One could press the standard objection by noting that while is that presently an inductive theory that could provide warrant for a unique system for weighting the various methodological it is overly pessimistic to think that we never have a principled for identifying a uniquely best system. is plausible, objection to that someday we have a uniquely best QAT, or perhaps uniquely best QATs for particular kinds of epistemic scenarios, and could thereby regarding the of from studies. To this have to forgive those medical scientists, response, who are concerned with assessing evidence today. there is deeper reason why such a response not compelling. 12 There is a tendency among scientists to suppose that the relative importance of various methodological features is merely an empirical need not entirely sympathize such methodological naturalism agree the expressed Cho and here: we lack reasons to prefer one weighting of methodological features another, regardless of whether one thinks of these reasons as principled. It is not mere argument from present reiterate-to that the poor inter-tool QATs that evidence particular studies is underdetermined. That because, as the example of Cho and Bero QAT are due to arbitrary differences in how the methodological features are weighed in the various There are, to be sure, better and worse QATs. But that is as good can do when it comes to distinguishing between Of those that account the majority of relevant methodological features, some weight those in slightly different than others, and have no principled for preferring one another. We not a inference that could help determine the of methodological features in QATs. If really one could sustain the objection by claiming that it is possible that in the future develop a theory of which
 weighting algorithm, and they Rightfully ClaimEd tHat SuCh arBitrAriness was justIFied Because "there is little emPiric [SiC] EvidENcE on thE relatiVE iMPOrtAnCe Of tHe INdIviduAl qUality cRiteria to tHe cOnTrol of systemATiC bias."12 MedicAl sCientists havE no PrinciPlEd fOUndatIon For deVelopiNG a uniqUely good QaT, ANd so reSOrt to a rELAtIvelY arbitrary basis foR ThEIr development. ONe coulD pREsS THe sTanDard objectIoN by noTIng that WHiLE IT is TRue that we presEntly lack an INduCtive tHeOry THat couLd proViDE waRrant for a unIque System for WeightINg the vaRIous metHodoloGicAl fEatuREs, It Is oVeRLy pESsImiSTic To think tHaT wE will NeveR HAVE a prIncIpleD basiS for identifyiNg a UniqUEly Best wEightIng sYsTem. It Is plauSible, ThIs objection goes, To thInk that soMedAy We wIlL have A UniqueLy bEst qAT, or peRhaps unIQueLy BEST QaTs for particular kiNdS OF ePistemic ScenarIOs, AnD We could tHeRebY achIEVe agrEemeNT rEgarding The strENgTh Of evideNcE from mEdIcaL stUdies. tO thiS one woUld have tO forgIVe those medical SCientists, dissATiSFIeD With ThiS response, whO are COnceRned WItH asSEssinG evidEnCE tODay. But there is anotheR, dEeper rEason Why such a respoNse is not coMPELling. 12 TheRe is A TeNDency among mediCal scIentists to SUppose thAt the Relative ImportancE OF various MetHodOloGicAL FeAtures is merelY AN empIrIcal matTer. one need Not EntIreLy sYmPathize wiTh such meThOdOlOgIcaL natuRAlism to aGrEe wItH thE poinT ExpresSed by cho aNd beRO heRe: we lacK ReASOns tO pReFer oNe wEiGhtinG of mEThoDologicAl featureS ovER anoThEr, RegardlEss of whether oNe Thinks of thEsE reAsons aS EMpirical Or principled. 19 It is not a merE ArgumenT frOm preSent DisagreemEnt-i reiteRatE-To claiM that tHe pooR iNteR-TOol reLIAbIliTy Of QATs implIES thAt the StRengTh of eviDence from particulaR MedIcal studies is UndErdeTERmIneD. thAT is BeCAusE, AS the example of thE Cho and BerO Qat sUggests, the DIsaGrEements Between qATs aRE due to aRbitrary dIfferenceS iN how THE paRticular meThodologIcal featuREs are WEiGhed iN thE varioUs qATS. TherE are, to BE suRe, betTer and WoRse QATS. But tHaT is about As good as one can do when it cOmes to DistiNguIshing betWeeN qATS. Of those tHat aCcount for tHe mAjoRity oF reLEvant MethODoLogICal feAturES, some weigHT tHosE FEaTures in a sliGHTLy dIfferEnt MAnner tHan oThers, and we have no pRIncipled groundS for PREfeRriNG one WeIghting over anoTheR. WE DO not possEsS a theory of sCientifiC iNFerenCe that Could hElp deteRMInE The weiGhts Of tHe methodoLogIcAL featurEs In qaTs. If oNe reAlLy wantEd to, onE CoulD SUstain the objectiOn by cLAIming THat It is pOsSible thAT in tHe future we Will develop A theorY of iNfereNce whicH wOuld
 weighting algorithm, andthey right fully  cl aim ed  tha t su ch arbitrarine s s wa s justified because "t hereis litt l eempir ic [sic ]  e v i den ce  o n t he re lativ e i mportan ce of theind iv idual qualit y  c riteria to  th e control of  sy stemat ic  bi a s."12  Me dical  scien t ists h ave no pr in c ipledf oundati o n  f or d eveloping a uniqu e ly good QAT, andso res or t  t o a r ela tively arb it raryb asis fo r  t h e i r d e velopment. On e could pre s s t he sta nd ard object ion b yn oti ng that whi le i t is true  thatw e prese n tly lac k an i ndu cti ve t h eo ry  th at cou l dpro v ide  warrant  f or  a un ique s y s temfor  wei ghtin g the various  me thod o log icalfeatu res,  i t isoverly  pess im istic to thinkthat  we willnev er  ha ve  a pr i nciple d b asi s for i dentify i ngau n i qu ely best weighting  s y s te m. It is  plaus i bl e, this obj ec tio n go e s , tothin k  t hat some day we wi ll  have a  u niquel ybes t Q AT, o r  per haps u niquelybestQ ATs for partic u lar kinds ofe pi s t em i c sc ena rios, and w e co u ld t here b yach i eve a greem en t  r e garding the strengt hof evi dence  from medical  studies.T o this one  wou l dh ave to forgive  thos e medicals cientist s, di ssatisfi ed with t h i s respon se,  wh o a rec o nc erned with as s e ssin gevidenc e t oday. B utthe reisan other, de eper rea so nwh ysuc h a r e sponse i snot  c omp ellin g . 12 T hereis a  t en d enc y among me d i calsc ie ntis tsto  supp oset hat  the re lative im por t ance  o fvarious  methodologic al  featuresis  me rely a n empirica l matter. One need note ntirely  sy mpath izewith such  me thodol ogi c al nat uralis m toag ree w ith t h e  p oin texpressedb y  Ch o and  B erohere: w e lack reasons top ref er one weight ing  ofm e th odo l og i cal  f e atu r e s over another,  regardles so fwhether on e  th in ks of t hese re asons as empi rical orprinciple d.  19I t  is  not a mer e argume nt from p r esent di sagre eme nt-I r ei ter ate-t o clai m  th at th e poor  i nter-t ool r el iability  of QATs implies that t he str ength  of  evidence  fr o m p articular  med ical studi esisunder det e rmine d. T h at  is becau se,a s the exa m pl e o f th e Cho and B e r o  QA T sug ges t s, the  dis agreements betwee n  QATs are dueto a r b itr ary diff er ences in how t hepa r t icular m et hodological  feature sa re we ighedin the  variou s QA T s. The re a re,  to be su re,  b e tter an dwo r se QAT s. B ut  thatis abo u t as g ood as one can d o whe n it co m esto di st inguish i ng b etween QAT s. Of those  thatacco unt f or thema jority  of  r elevant me t hodologic al fe atures,  s omewei ght th osef e ature s in  a  sl ightly di f f er e nt  m a nne r th an ot he rs,and we ha v e no pri nci p led gro un dsf o r pref e rr i n g one weig hti ng ov e r  another.W e do no t  poss ess atheory  of sci e nti fi c infer enc e that coul d help de t erm in e th e weight sof t he  me th odological feat ures inQATs. If o ne rea lly want e d to,on e could sust ain t he objecti o n  by  claimi n g t hat  it  ispos sibl e  that in the future we w illdevel o p a  theo ry of  i nference whic h would
 weighting_algorithm, and_they rightfully claimed that_such arbitrariness_was_justified because_"there_is little empiric_[sic] evidence on_the relative importance of_the individual quality_criteria_to the control of systematic bias."12 Medical scientists have no principled foundation for developing_a_uniquely good_QAT,_and_so resort to a relatively_arbitrary basis for their development._One could_press the standard objection by noting that while_it_is true that_we presently lack an inductive theory that could provide_warrant for a unique system for_weighting the various_methodological_features,_it is overly pessimistic_to think that we will never_have a principled basis for identifying_a uniquely best weighting system. It is_plausible, this objection goes, to think_that someday we will have_a uniquely_best QAT, or perhaps uniquely_best QATs for_particular kinds_of epistemic scenarios,_and we could thereby achieve agreement_regarding the strength_of evidence from medical studies. To_this_one would have_to_forgive_those medical_scientists, dissatisfied with_this_response, who_are_concerned with assessing evidence today. But_there_is another, deeper reason why such a_response is not compelling._12_There is a tendency_among medical scientists to suppose_that the relative importance of various_methodological features_is merely_an empirical matter. One need not entirely sympathize with such methodological_naturalism to agree with the point_expressed by Cho and_Bero here:_we_lack reasons to_prefer_one weighting_of methodological features over another, regardless of_whether one_thinks of these reasons as empirical_or principled. 19 It_is_not a mere argument from present_disagreement-I reiterate-to claim that the poor_inter-tool reliability of QATs implies_that_the_strength of evidence from particular_medical studies is underdetermined. That is_because, as the_example of the Cho and Bero QAT_suggests,_the disagreements between QATs are due_to_arbitrary differences in how the particular_methodological_features_are weighed in the various_QATs. There are, to be sure,_better and worse QATs. But that is about as_good as one_can do when it comes_to_distinguishing_between QATs. Of those that account for the majority of_relevant methodological_features, some weight_those features in a slightly different manner than others, and_we have no principled grounds for preferring_one weighting over another. We do not possess a theory of_scientific inference that could help determine the weights_of the methodological features in QATs. If_one really wanted to,_one_could sustain the objection by claiming that_it_is_possible_that in the_future we will_develop a theory_of inference_which would