Outcome reporting in industry-sponsored trials of gabapentin for off-label use

S. Swaroop Vedula, Lisa Bero, Roberta Scherer, Kay Dickersin

Research output: Contribution to journalArticle

Abstract

BACKGROUND: There is good evidence of selective outcome reporting in published reports of randomized trials. METHODS: We examined reporting practices for trials of gabapentin funded by Pfizer and Warner-Lambert's subsidiary, Parke-Davis (hereafter referred to as Pfizer and Parke-Davis) for off-label indications (prophylaxis against migraine and treatment of bipolar disorders, neuropathic pain, and nociceptive pain), comparing internal company documents with published reports. RESULTS: We identified 20 clinical trials for which internal documents were available from Pfizer and Parke-Davis; of these trials, 12 were reported in publications. For 8 of the 12 reported trials, the primary outcome defined in the published report differed from that described in the protocol. Sources of disagreement included the introduction of a new primary outcome (in the case of 6 trials), failure to distinguish between primary and secondary outcomes (2 trials), relegation of primary outcomes to secondary outcomes (2 trials), and failure to report one or more protocol-defined primary outcomes (5 trials). Trials that presented findings that were not significant (P≥0.05) for the protocol-defined primary outcome in the internal documents either were not reported in full or were reported with a changed primary outcome. The primary outcome was changed in the case of 5 of 8 published trials for which statistically significant differences favoring gabapentin were reported. Of the 21 primary outcomes described in the protocols of the published trials, 6 were not reported at all and 4 were reported as secondary outcomes. Of 28 primary outcomes described in the published reports, 12 were newly introduced. CONCLUSIONS: We identified selective outcome reporting for trials of off-label use of gabapentin. This practice threatens the validity of evidence for the effectiveness of off-label interventions.

Original languageEnglish (US)
Pages (from-to)1963-1971
Number of pages9
JournalNew England Journal of Medicine
Volume361
Issue number20
DOIs
StatePublished - Nov 12 2009

Fingerprint

Off-Label Use
Industry
Nociceptive Pain
Neuralgia
Clinical Protocols
Migraine Disorders
Bipolar Disorder
Publications
Clinical Trials
gabapentin
Therapeutics

ASJC Scopus subject areas

  • Medicine(all)

Cite this

Outcome reporting in industry-sponsored trials of gabapentin for off-label use. / Vedula, S. Swaroop; Bero, Lisa; Scherer, Roberta; Dickersin, Kay.

In: New England Journal of Medicine, Vol. 361, No. 20, 12.11.2009, p. 1963-1971.

Research output: Contribution to journalArticle

@article{f591e2b124654217aa893540c7a9c285,
title = "Outcome reporting in industry-sponsored trials of gabapentin for off-label use",
abstract = "BACKGROUND: There is good evidence of selective outcome reporting in published reports of randomized trials. METHODS: We examined reporting practices for trials of gabapentin funded by Pfizer and Warner-Lambert's subsidiary, Parke-Davis (hereafter referred to as Pfizer and Parke-Davis) for off-label indications (prophylaxis against migraine and treatment of bipolar disorders, neuropathic pain, and nociceptive pain), comparing internal company documents with published reports. RESULTS: We identified 20 clinical trials for which internal documents were available from Pfizer and Parke-Davis; of these trials, 12 were reported in publications. For 8 of the 12 reported trials, the primary outcome defined in the published report differed from that described in the protocol. Sources of disagreement included the introduction of a new primary outcome (in the case of 6 trials), failure to distinguish between primary and secondary outcomes (2 trials), relegation of primary outcomes to secondary outcomes (2 trials), and failure to report one or more protocol-defined primary outcomes (5 trials). Trials that presented findings that were not significant (P≥0.05) for the protocol-defined primary outcome in the internal documents either were not reported in full or were reported with a changed primary outcome. The primary outcome was changed in the case of 5 of 8 published trials for which statistically significant differences favoring gabapentin were reported. Of the 21 primary outcomes described in the protocols of the published trials, 6 were not reported at all and 4 were reported as secondary outcomes. Of 28 primary outcomes described in the published reports, 12 were newly introduced. CONCLUSIONS: We identified selective outcome reporting for trials of off-label use of gabapentin. This practice threatens the validity of evidence for the effectiveness of off-label interventions.",
author = "Vedula, {S. Swaroop} and Lisa Bero and Roberta Scherer and Kay Dickersin",
year = "2009",
month = "11",
day = "12",
doi = "10.1056/NEJMsa0906126",
language = "English (US)",
volume = "361",
pages = "1963--1971",
journal = "New England Journal of Medicine",
issn = "0028-4793",
publisher = "Massachussetts Medical Society",
number = "20",

}

TY - JOUR

T1 - Outcome reporting in industry-sponsored trials of gabapentin for off-label use

AU - Vedula, S. Swaroop

AU - Bero, Lisa

AU - Scherer, Roberta

AU - Dickersin, Kay

PY - 2009/11/12

Y1 - 2009/11/12

N2 - BACKGROUND: There is good evidence of selective outcome reporting in published reports of randomized trials. METHODS: We examined reporting practices for trials of gabapentin funded by Pfizer and Warner-Lambert's subsidiary, Parke-Davis (hereafter referred to as Pfizer and Parke-Davis) for off-label indications (prophylaxis against migraine and treatment of bipolar disorders, neuropathic pain, and nociceptive pain), comparing internal company documents with published reports. RESULTS: We identified 20 clinical trials for which internal documents were available from Pfizer and Parke-Davis; of these trials, 12 were reported in publications. For 8 of the 12 reported trials, the primary outcome defined in the published report differed from that described in the protocol. Sources of disagreement included the introduction of a new primary outcome (in the case of 6 trials), failure to distinguish between primary and secondary outcomes (2 trials), relegation of primary outcomes to secondary outcomes (2 trials), and failure to report one or more protocol-defined primary outcomes (5 trials). Trials that presented findings that were not significant (P≥0.05) for the protocol-defined primary outcome in the internal documents either were not reported in full or were reported with a changed primary outcome. The primary outcome was changed in the case of 5 of 8 published trials for which statistically significant differences favoring gabapentin were reported. Of the 21 primary outcomes described in the protocols of the published trials, 6 were not reported at all and 4 were reported as secondary outcomes. Of 28 primary outcomes described in the published reports, 12 were newly introduced. CONCLUSIONS: We identified selective outcome reporting for trials of off-label use of gabapentin. This practice threatens the validity of evidence for the effectiveness of off-label interventions.

AB - BACKGROUND: There is good evidence of selective outcome reporting in published reports of randomized trials. METHODS: We examined reporting practices for trials of gabapentin funded by Pfizer and Warner-Lambert's subsidiary, Parke-Davis (hereafter referred to as Pfizer and Parke-Davis) for off-label indications (prophylaxis against migraine and treatment of bipolar disorders, neuropathic pain, and nociceptive pain), comparing internal company documents with published reports. RESULTS: We identified 20 clinical trials for which internal documents were available from Pfizer and Parke-Davis; of these trials, 12 were reported in publications. For 8 of the 12 reported trials, the primary outcome defined in the published report differed from that described in the protocol. Sources of disagreement included the introduction of a new primary outcome (in the case of 6 trials), failure to distinguish between primary and secondary outcomes (2 trials), relegation of primary outcomes to secondary outcomes (2 trials), and failure to report one or more protocol-defined primary outcomes (5 trials). Trials that presented findings that were not significant (P≥0.05) for the protocol-defined primary outcome in the internal documents either were not reported in full or were reported with a changed primary outcome. The primary outcome was changed in the case of 5 of 8 published trials for which statistically significant differences favoring gabapentin were reported. Of the 21 primary outcomes described in the protocols of the published trials, 6 were not reported at all and 4 were reported as secondary outcomes. Of 28 primary outcomes described in the published reports, 12 were newly introduced. CONCLUSIONS: We identified selective outcome reporting for trials of off-label use of gabapentin. This practice threatens the validity of evidence for the effectiveness of off-label interventions.

UR - http://www.scopus.com/inward/record.url?scp=70449633381&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=70449633381&partnerID=8YFLogxK

U2 - 10.1056/NEJMsa0906126

DO - 10.1056/NEJMsa0906126

M3 - Article

C2 - 19907043

AN - SCOPUS:70449633381

VL - 361

SP - 1963

EP - 1971

JO - New England Journal of Medicine

JF - New England Journal of Medicine

SN - 0028-4793

IS - 20

ER -