Á lv a ro N a g ib A ta lla h *
D ealin g w ith p u b licatio n b ias
T
h e rew ith p o s itiv eis a h u m a nre s u lts .tre n d to . p u ~ lis h ju s t c lin ic ~ l tria lsT h lS k ln d o f s y s te m a tlc e rro r . o r b ia s te n d s to m is le a d th e re a d e rs . F a u lts o f th isn a tu re a re a ttrib u ta b le to E d ito rs ' p re fe re n c e s fo r c a u s in g
s c ie n tific im p a c t w ith th e ir p u b lic a tio n s , b u t e v id e n c e h a s
a ls o re c e n tly b e e n p u t fo rw a rd th a t th e a u th o rs o f c lin ic a I
tria ls w h ic h d id n o t d e te c t th e e ffe c t o f n e w tre a tm e n t te n d
n o t to s u b m it th e re s p e c tiv e p a p e rs fo r p u b lic a tio n 1 .
T h e re s u lt is th a t w h e n p u b lic a tio n b ia s o c c u rs , th e re
is th e p ro b a b ility th a t th e re s u lts o f re v ie w s w ill b e
in c o rre c t. B e c a u s e o f th is , th e C o c h ra n e C o lla b o ra tio n
re v ie w e rs h a v e ta k e n o n th e c o m m itm e n t to s e a rc h fo r a ll
e x is tin g c lin ic a I tria ls re g a rd in g a s p e c ific th e ra p e u tic s
q u e s tio n , p u b lis h e d o r n o te In o th e r w o rd s , th e v a lu e o f a
p a rtic u la r tria l d e p e n d s m o re o n th e m e th o d s in c lu d e d in
its d e s ig n a n d d e v e lo p m e n t, th a n o n w h a t jo u m a l it w a s
p u b lis h e d in .
In o rd e r to c o n trib u te to th is s u b je c t, th e S ã o P a u lo
M e d ic a I J o u rn a l is jo in in g th e b e s t in te rn a tio n a l jo u rn a ls ,
lik e th e L a n c e t, th e B ritis h M e d ic a I J o u m a l a n d th e J A M A ,
in th e U n p u b lis h e d T ria ls A m n e s ty C a m p a ig n . B ra z ilia n
c o lle a g u e s w h o h a v e u n p u b lis h e d c lin ic a I tria ls m a y fill
in a n d re tu m th e fo rm in c lu d e d in th is is s u e , o r s e n d th e
fu ll p a p e r to th e S ã o P a u lo M e d ic a I J o u rn a I, s o th a t th e y
w ill h a v e a c h a n c e o f b e in g in c lu d e d in a p u b lic a tio n o r a t
le a s t in th e C o c h ra n e D a ta b a s e o f C lin ic a I T ria ls . T h u s ,
th e y w ill g a in th e v is ib ility to b e in c lu d e d in s y s te m a tic
re v ie w s a n d g e t c ita tio n s a n d re c o g n itio n . M o re d e ta ils
m a y b e o b ta in e d in th e n e x t p a p e r b y Ia in R o b e rts a n d
R ic h a rd S m ith , e d ito r o f th e B ritis h M e d ic a I J o u rn a l.
*M D , P h D , M C E
C h a im a n , D iv is io n o f In te rn a I M e d ic in e , E s c o la
P a u lis ta d e M e d ic in a , E d ito r S ã o P a u lo M e d ic a I J o u rn a l.
IIA n a m n e s ty fo r u n p u b lis h e d tria ls . S e n d u s d e ta ils
o n
a n y u n re p o rte d tria lsT h is m o n th o v e r 1 0 0 m e d ic a I jo u rn a ls a ro u n d th e
w o rld a re in v itin g re a d e rs to s e n d in fo rm a tio n o n
u n p u b lis h e d tria ls . T h is a m n e s ty s h o u ld h a v e im p o rta n t
b e n e fits fo r p a tie n ts . W h y ?
R e p o rts o f p ro p e rly c o n d u c te d ra n d o m is e d c o n tro lle d
tria ls a re th e fo u n d a tio n o f e ffe c tiv e h e a lth c a re , b u t m a n y
a re n o t s u b m itte d fo r p u b lic a tio n 1 ,2T h is re d u c e s th e p o w e r
o f s y s te m a tic re v ie w s to d e te c t m o d e ra te b u t c lin ic a lly
im p o rta n t tre a tm e n t e ffe c ts . P a tie n ts m a y th u s b e d e n ie d
e ffe c tiv e fo rm s o f h e a lth c a re . A s e c o n d p ro b le m is th a t.
s in c e tria Is th a t s h o w m o re p ro m is in g e ffe c ts a re m o re
Iik e Iy to b e s u b m itte d , re s e a rc h s y n th e s e s c a n g iv e
m is le a d in g c o n c lu s io n s a b o u t e ffe c tiv e n e s s . P a tie n ts m a y
th u s b e e x p o s e d to u s e le s s o r e v e n h a rm fu l tre a tm e n ts .3
F in a l1 y , p a tie n ts m a y b e a s k e d to p a rtic ip a te in n e w s tu d ie s
d e s ig n e d to a d d re s s q u e s tio n s th a t h a v e a lre a d y b e e n
a n s w e re d .4
T ria Is g o u n re p o rte d fo r a m y ria d o f re a s o n s : it is
w e ll d o c u m e n te d th a t tria ls w ith n o n -s ig n ific a n t re s u lts
a re s u b s ta n tia l1 y le s s lik e ly to b e s u b m itte d fo r p u b lic a tio n .1
S o m e tim e s re c ru itin g p a rtic i p a n ts ta k e s lo n g e r th a n
e x p e c te d a t th e e x p e n s e o f tim e s e t a s id e fo r re p o rt w ritin g ;
in v e s tig a to rs m a y c h a n g e jo b s a n d w o rk re m a in u n fin is h e d ;
o r in v e s tig a to rs m a y d is c o v e r a re c e n tIy p u b lis h e d tria l o n
th e s a m e to p ic a n d c o n c lu d e th a t th e ir o w n re s u lts a re
re d u n d a n te E d ito rs m u s t a ls o ta k e s o m e re s p o n s ib ility :
th e re is a lim it to th e n u m b e r o f re p o rts w e c a n p u b lis h .
M a n y in v e s tig a to rs re g re t n o t h a v in g p u b lis h e d th e ir
re s u Its , a n d w h e n c o n ta c te d a lm o s t a ll a re d e lig h te d to
p ro v id e th e m .
A T A L L A H , A . N - D e a lin g w it h p u b lic a t io n b ia s
t.~W *,,~~,*,~'ID .~:~l\\}.;\~~m .~~~~~W ~~~~~~~~~~~\~~~~~~~~~Th~~'2ê~:;::m m ~~~~m :'2ê~~ ~~.~>':\ ~"'~>::m ::l>.~"""~ .. :;::m 3t~~>:;::m ' ~. >~>N :::m ::l"'Ji:;::m '2ê~> ::m ::l.~m
1528
REFERENCES
1. D ickersin K , M in Y I. N IH clinicaI trials and publication
bias. O n-line J Curr Clin Trials [serial online] 1993; 28 A pr:
D oc N o 50.
Easterbrook PJ, Berlin JA , G opalan R, M atthew s D R.
Publication bias in clinicai research. Lancet 1991;337:867-72.
3. Egger M , D avey Sm ith G . M isleading m eta-analysis. BM J
1995;310:752-4.
4. Savulescu J, Chalm ers I, Blunt J. A re research ethics
com m ittees behaving unethically? Som e suggestions for
im proving perform ance and accountability. BM J
1996;313: 1390-3.
because of the serious im plications of unreported research, w e are trying to cleave the trials from the tribulations. W e are confident of a good response."
Richard Sm ith - Editor, BM J Ian Roberts - D irector Child H ealth M onitoring U nit, Institute of Child H ealth, London W CIN lEH A lthough am nesty m eans giving pardon, w e hope
that investigators w ill see this as an opportunity-nam ely, to m ake the results of previously unreported trials publicly accessible, thus having the potential to contribute to the .. scientific foundation of health care. W e urge alI investigators w ith unreported trial data to register their trials by returninga photocopy of the registration form show n below . W e w ould like to register any unreported controlled trial, including trials that have ~nly been published as an abstract.
Registration can be undertaken by anyone able to provide the registration inform ation, even if they cannot provide the actual trial data. W e expect a degree of duplicate registration. The inform ation w ill be m ade available by listing the trial details on a w eb 'site and in other w ays. If specific trial data are required, for exam ple . by those conducting system atic review s, then the review er 2.
w ill be able to seek this inform ation directly from the trialist. Som e of the trials m ay be suitable for full publication, and the journal w ill be happy to consider these.
M edicaI editors are acutely aw are of the trials and tribulations of research reporting. O n this occasion,
x - - - _ . : . -
- - - . - ': - "
-U nreported
trial registration
form
Register any controlled trial w hich has not been published in fu11, including trials that have been published only as an abstract. Registratio~ can be undertaken by anyone able to provide registration inform ation, even if they are unable to provide the actual trial data. Please com plete one form for each trial being registered.
Contact details
Surnam e:
Postal address: _
Forenam e~):_~~~~~~~~~~~~~_
Phone (w ith regional codes): ~ _ Fax (w ith regional codes): ~ -Em ail: ~~~~~~~~~~~~~~~~_
Trial details
A pproxim ate num ber of participants in the tria1"'lo.L. _ Type of participants (eg people w ith head injury, w om en at risk of breast
cancer):---Type of intervention (eg steroids versus placebo, annual m am m ography versus standard practice: _
____________________ versus _
Please post or fax registration form s to: M edicaI Editors' Trial A m nesty, BM J Editorial D epartm ent, Tavistock Square, London W CIH 9JR. Fax: 44 (O) 171 383 6418. A lternatively the inform ation can be sent by em ail to:
m eta@ uc1.ac.uk
