Asbjørn Hróbjartsson

Summary

Affiliation: Det Nordiske Cochrane Center
Country: Denmark

Publications

  1. ncbi Observer bias in randomized clinical trials with measurement scale outcomes: a systematic review of trials with both blinded and nonblinded assessors
    Asbjørn Hróbjartsson
    Nordic Cochrane Centre, Rigshospitalet Department 7811, Copenhagen, Denmark
    CMAJ 185:E201-11. 2013
  2. ncbi Observer bias in randomised clinical trials with binary outcomes: systematic review of trials with both blinded and non-blinded outcome assessors
    Asbjørn Hróbjartsson
    Nordic Cochrane Centre, Rigshospitalet Department 3343, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark
    BMJ 344:e1119. 2012
  3. ncbi Effect of osteosynthesis, primary hemiarthroplasty, and non-surgical management for displaced four-part fractures of the proximal humerus in elderly: a multi-centre, randomised clinical trial
    Stig Brorson
    Dept of Orthopaedic Surgery, Herlev University Hospital, Herlev, Denmark
    Trials 10:51. 2009
  4. ncbi Placebo effect studies are susceptible to response bias and to other types of biases
    Asbjørn Hróbjartsson
    The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark
    J Clin Epidemiol 64:1223-9. 2011
  5. ncbi Clinical placebo interventions are unethical, unnecessary, and unprofessional
    Asbjørn Hróbjartsson
    Nordic Cochrane Centre, Rigshospitalet, Copenhagen
    J Clin Ethics 19:66-9. 2008
  6. ncbi [Johannes Fibiger and the controlled clinical trial]
    Asbjørn Hróbjartsson
    Det Nordiske Cochrane Center, Rigshospitalet, DK 2100 København Ø
    Ugeskr Laeger 169:2876. 2007
  7. ncbi Reporting on blinding in trial protocols and corresponding publications was often inadequate but rarely contradictory
    Asbjørn Hróbjartsson
    The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark
    J Clin Epidemiol 62:967-73. 2009
  8. ncbi [A new scientific source of bias: SILLY bias. Analysis of citations of BMJ's Christmas articles]
    Ulrik A Felding
    Det Nordiske Cochrane Center, Rigshospitalet, København Ø
    Ugeskr Laeger 171:3784-9. 2009
  9. ncbi Blinding in randomized clinical trials: imposed impartiality
    A Hrobjartsson
    The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark
    Clin Pharmacol Ther 90:732-6. 2011
  10. ncbi Unsubstantiated claims of large effects of placebo on pain: serious errors in meta-analysis of placebo analgesia mechanism studies
    Asbjørn Hróbjartsson
    The Nordic Cochrane Centre, Rigshospitalet, Denmark
    J Clin Epidemiol 59:336-8; discussion 339-41. 2006

Collaborators

Detail Information

Publications24

  1. ncbi Observer bias in randomized clinical trials with measurement scale outcomes: a systematic review of trials with both blinded and nonblinded assessors
    Asbjørn Hróbjartsson
    Nordic Cochrane Centre, Rigshospitalet Department 7811, Copenhagen, Denmark
    CMAJ 185:E201-11. 2013
    ..We wanted to evaluate the effect of nonblinded outcome assessment on estimated effects in randomized clinical trials with outcomes that involved subjective measurement scales...
  2. ncbi Observer bias in randomised clinical trials with binary outcomes: systematic review of trials with both blinded and non-blinded outcome assessors
    Asbjørn Hróbjartsson
    Nordic Cochrane Centre, Rigshospitalet Department 3343, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark
    BMJ 344:e1119. 2012
    ..To evaluate the impact of non-blinded outcome assessment on estimated treatment effects in randomised clinical trials with binary outcomes...
  3. ncbi Effect of osteosynthesis, primary hemiarthroplasty, and non-surgical management for displaced four-part fractures of the proximal humerus in elderly: a multi-centre, randomised clinical trial
    Stig Brorson
    Dept of Orthopaedic Surgery, Herlev University Hospital, Herlev, Denmark
    Trials 10:51. 2009
    ..A blinded physiotherapist will carry out the assessments. Other secondary outcomes are Oxford Shoulder Score, and general health status (Short Form-36)...
  4. ncbi Placebo effect studies are susceptible to response bias and to other types of biases
    Asbjørn Hróbjartsson
    The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark
    J Clin Epidemiol 64:1223-9. 2011
    ..The history of placebo shows that assessment of its clinical significance has a real potential to be biased. We analyze and discuss typical types of bias in studies on placebo...
  5. ncbi Clinical placebo interventions are unethical, unnecessary, and unprofessional
    Asbjørn Hróbjartsson
    Nordic Cochrane Centre, Rigshospitalet, Copenhagen
    J Clin Ethics 19:66-9. 2008
  6. ncbi [Johannes Fibiger and the controlled clinical trial]
    Asbjørn Hróbjartsson
    Det Nordiske Cochrane Center, Rigshospitalet, DK 2100 København Ø
    Ugeskr Laeger 169:2876. 2007
  7. ncbi Reporting on blinding in trial protocols and corresponding publications was often inadequate but rarely contradictory
    Asbjørn Hróbjartsson
    The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark
    J Clin Epidemiol 62:967-73. 2009
    ..To compare the reporting on blinding in protocols and articles describing randomized controlled trials...
  8. ncbi [A new scientific source of bias: SILLY bias. Analysis of citations of BMJ's Christmas articles]
    Ulrik A Felding
    Det Nordiske Cochrane Center, Rigshospitalet, København Ø
    Ugeskr Laeger 171:3784-9. 2009
    ..Thus, we document a new type of bias in medical research: Serious Idiopathic Loss of Ludic ironY (SILLY) bias, both in citation practices and in metaanalyses...
  9. ncbi Blinding in randomized clinical trials: imposed impartiality
    A Hrobjartsson
    The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark
    Clin Pharmacol Ther 90:732-6. 2011
    ..We encourage extensive pretrial testing of blinding procedures and explicit reporting of who was in the blinded condition and the methods used to ensure blinding...
  10. ncbi Unsubstantiated claims of large effects of placebo on pain: serious errors in meta-analysis of placebo analgesia mechanism studies
    Asbjørn Hróbjartsson
    The Nordic Cochrane Centre, Rigshospitalet, Denmark
    J Clin Epidemiol 59:336-8; discussion 339-41. 2006
  11. ncbi Ghost authorship in industry-initiated randomised trials
    Peter C Gøtzsche
    Nordic Cochrane Centre, Copenhagen, Denmark
    PLoS Med 4:e19. 2007
    ..The prevalence and nature of ghost authorship in industry-initiated randomised trials is not known...
  12. ncbi [Constraints on publication rights in industry-initiated clinical trials--secondary publication]
    Peter C Gøtzsche
    H S Rigshospitalet, Det Nordiske Cochrane Center, DK 2100 København Ø
    Ugeskr Laeger 168:2467-9. 2006
    ..These facts were not noted in any of the trial reports. We found similar constraints on publication rights in 44 protocols from 2004. This tight sponsor control over industry-initiated trials should be changed...
  13. ncbi Conflicts of interest at medical journals: the influence of industry-supported randomised trials on journal impact factors and revenue - cohort study
    Andreas Lundh
    The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark
    PLoS Med 7:e1000354. 2010
    ..We investigated industry-supported trials' influence on journal impact factors and revenue...
  14. ncbi Powerful spin in the conclusion of Wampold et al.'s re-analysis of placebo versus no-treatment trials despite similar results as in original review
    Asbjørn Hróbjartsson
    Hróbjartsson, The Nordic CochraneCentre, Rigshospitalet, Department 7112, Blegdamsvej 9, DK 2100 Copenhagen Ø
    J Clin Psychol 63:373-7. 2007
    ..95 (95% confidence interval = 0.88-1.02) versus odds ratio 0.99 (95% confidence interval = 0.81-1.23). Thus, B. E. Wampold et al.'s conclusion was not substantiated by their data, and is best characterized as powerful spin. ...
  15. ncbi What are the main methodological problems in the estimation of placebo effects?
    Asbjørn Hróbjartsson
    Department of Medical Philosophy and Clinical Theory, University of Copenhagen, Panum Institute, Blegdamsvej 3, DK 220 Ø Copenhagen N, Denmark
    J Clin Epidemiol 55:430-5. 2002
    ..The effect of patient-provider interaction can similarly be assessed by comparing manipulation of the patient-provider interaction with no manipulation. In both cases bias due to lack of double-blinding is a potential problem...
  16. ncbi [What is the effect of placebo interventions? A systematic review of randomized clinical trials with placebo treated and untreated patients]
    Asbjørn Hróbjartsson
    Afdeling for Medicinsk Videskabsteori, Københavns Universitet, Panum Instituttet, DK 2200 København N
    Ugeskr Laeger 164:329-33. 2002
    ..Placebo treatments have been reported to help patients with many diseases, but the quality of the evidence supporting this belief has not been rigorously evaluated...
  17. ncbi [Selective reporting of positive outcomes in randomised trials--secondary publication.. A comparison of protocols with published reports]
    Asbjørn Hróbjartsson
    H S Rigshopitalet, Det Nordiske Cochrane Center, University Health Network Toronto, Department of Medicine
    Ugeskr Laeger 167:3189-91. 2005
    ..Selective reporting of positive outcomes is associated with bias...
  18. ncbi Data extraction errors in meta-analyses that use standardized mean differences
    Peter C Gøtzsche
    Nordic Cochrane Centre, Rigshospitalet, Copenhagen Ø, Denmark
    JAMA 298:430-7. 2007
    ..It is not known how reliable such meta-analyses are...
  19. ncbi Comparison of descriptions of allocation concealment in trial protocols and the published reports: cohort study
    Julie Pildal
    Nordic Cochrane Centre, H S Rigshospitalet, DK 2100 Copenhagen, Denmark
    BMJ 330:1049. 2005
    ....
  20. ncbi Who is blinded in randomized clinical trials? A study of 200 trials and a survey of authors
    Mette Thorlund Haahr
    The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark
    Clin Trials 3:360-5. 2006
    ..Insufficient blinding of persons involved in randomized clinical trials is associated with bias. The appraisal of the risk of bias is difficult without adequate information in trial reports...
  21. ncbi Disagreements in meta-analyses using outcomes measured on continuous or rating scales: observer agreement study
    Britta Tendal
    Nordic Cochrane Centre, Rigshospitalet, Dept 3343, Blegdamsvej 9, DK 2100 Copenhagen, Denmark
    BMJ 339:b3128. 2009
    ..To study the inter-observer variation related to extraction of continuous and numerical rating scale data from trial reports for use in meta-analyses...
  22. ncbi Spontaneous improvement in randomised clinical trials: meta-analysis of three-armed trials comparing no treatment, placebo and active intervention
    Lasse Theis Krogsbøll
    The Nordic Cochrane Centre, Rigshospitalet, Dept, 3343, Blegdamsvej 9, DK 2100 Copenhagen, Denmark
    BMC Med Res Methodol 9:1. 2009
    ..It is not known to which extent spontaneous improvement, effect of placebo and effect of active interventions contribute to the observed change from baseline, and we aimed at quantifying these contributions...
  23. ncbi Acupuncture treatment for pain: systematic review of randomised clinical trials with acupuncture, placebo acupuncture, and no acupuncture groups
    Matias Vested Madsen
    Nordic Cochrane Centre, Rigshospitalet, Department 3343, Blegdamsvej 9, DK 2100 Copenhagen, Denmark
    BMJ 338:a3115. 2009
    ..To study the analgesic effect of acupuncture and placebo acupuncture and to explore whether the type of the placebo acupuncture is associated with the estimated effect of acupuncture...
  24. ncbi Divine intervention? A Cochrane review on intercessory prayer gone beyond science and reason
    Karsten Juhl Jørgensen
    Dept 3343, The Nordic Cochrane Centre, Rigshospitalet, DK 2100 Copenhagen, Denmark
    J Negat Results Biomed 8:7. 2009
    ..The review fails to live up to the high standards required for Cochrane reviews...