Poynard, T; Thabut, D; Munteanu, M; Ratziu, V; Benhamou, Y; Deckmyn, O. 2010. Hirsch Index and Truth Survival in Clinical Research. PLOS ONE 5 (8): art. no.-e12044

[Eugene Garfield]

Poynard, T; Thabut, D; Munteanu, M; Ratziu, V; Benhamou, Y; Deckmyn, O. 
2010. Hirsch Index and Truth Survival in Clinical Research. PLOS ONE 5 (8): art. 
no.-e12044.

Author Full Name(s): Poynard, Thierry; Thabut, Dominique; Munteanu, Mona; 
Ratziu, Vlad; Benhamou, Yves; Deckmyn, Olivier

Language: English
Document Type: Article
KeyWords Plus: H-INDEX; INDIVIDUAL SCIENTISTS; TRIALS; OUTPUT

Abstract: Background: Factors associated with the survival of truth of clinical 
conclusions in the medical literature are unknown. We hypothesized that 
publications with a first author having a higher Hirsch' index value (h-I), which 
quantifies and predicts an individual's scientific research output, should have a 
longer half-life.
Methods and Results: 474 original articles concerning cirrhosis or hepatitis 
published from 1945 to 1999 were selected. The survivals of the main 
conclusions were updated in 2009. The truth survival was assessed by time-
dependent methods (Kaplan Meier method and Cox). A conclusion was 
considered to be true, obsolete or false when three or more observers out of 
the six stated it to be so. 284 out of 474 conclusions (60%) were still 
considered true, 90 (19%) were considered obsolete and 100 (21%) false. The 
median of the h-I was = 24 (range 1-85). Authors with true conclusions had 
significantly higher h-I (median = 28) than those with obsolete (h-I = 19; P = 
0.002) or false conclusions (h-I = 19; P = 0.01). The factors associated 
(P<0.0001) with h-I were: scientific life (h-I = 33 for. 30 years vs. 16 for, 30 
years), -methodological quality score (h-I = 36 for high vs. 20 for low scores), 
and -positive predictive value combining power, ratio of true to not-true 
relationships and bias (h-I = 33 for high vs. 20 for low values). In multivariate 
analysis, the risk ratio of h-I was 1.003 (95% CI, 0.994-1.011), and was not 
significant (P = 0.56). In a subgroup restricted to 111 articles with a negative 
conclusion, we observed a significant independent prognostic value of h-I (risk 
ratio = 1.033; 95% CI, 1.008-1.059; P = 0.009). Using an extrapolation of h-I 
at the time of article publication there was a significant and independent 
prognostic value of baseline h-I (risk ratio = 0.027; P = 0.0001).
Conclusions: The present study failed to clearly demonstrate that the h-index 
of authors was a prognostic factor for truth survival. However the h-index was 
associated with true conclusions, methodological quality of trials and positive 
predictive values.

Addresses: [Poynard, Thierry; Thabut, Dominique; Ratziu, Vlad; Benhamou, 
Yves] Univ Paris 06, AP HP, Grp Hosp Pitie Salpetriere, Liver Ctr,Serv 
Hepatogastroenterol, Paris, France; [Munteanu, Mona; Deckmyn, Olivier] 
Biopredictive, Paris, France

Reprint Address: Poynard, T, Univ Paris 06, AP HP, Grp Hosp Pitie Salpetriere, 
Liver Ctr,Serv Hepatogastroenterol, Paris, France.

E-mail Address: tpoynard at teaser.fr
ISSN: 1932-6203
DOI: 10.1371/journal.pone.0012044
fulltext: http://www.plosone.org/article/info:doi/10.1371/journal.pone.0012044