Published 12 January 2009, doi:10.1136/bmj.a3006
Cite this as: BMJ 2009;338:a3006

Research

Reporting and interpretation of SF-36 outcomes in randomised trials: systematic review

Despina G Contopoulos-Ioannidis, assistant professor1,2, Anastasia Karvouni, research fellow3, Ioanna Kouri, research fellow3, John P A Ioannidis, professor3,4

1 Department of Paediatrics, University of Ioannina School of Medicine, Ioannina, Greece, 2 Department of Paediatrics, George Washington University, School of Medicine and Health Sciences, Washington, DC, USA, 3 Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Greece, 4 Institute for Clinical Research and Health Policy Studies, Tufts University School of Medicine, Boston, MA, USA

Correspondence to: J P A Ioannidis, Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Ioannina 45110, Greece jioannid{at}cc.uoi.gr

Objective To determine how often health surveys and quality of life evaluations reach different conclusions from those of primary efficacy outcomes and whether discordant results make a difference in the interpretation of trial findings.

Design Systematic review.

Data sources PubMed, contact with authors for missing information, and author survey for unpublished SF-36 data.

Study selection Randomised trials with SF-36 outcomes (the most extensively validated and used health survey instrument for appraising quality of life) that were published in 2005 in 22 journals with a high impact factor.

Data extraction Analyses on the two composite and eight subdomain SF-36 scores that corresponded to the time and mode of analysis of the primary efficacy outcome.

Results Of 1057 screened trials, 52 were identified as randomised trials with SF-36 results (66 separate comparisons). Only eight trials reported all 10 SF-36 scores in the published articles. For 21 of the 66 comparisons, SF-36 results were discordant for statistical significance compared with the results for primary efficacy outcomes. Of 17 statistically significant SF-36 scores where primary outcomes were not also statistically significant in the same direction, the magnitude of effect was small in six, moderate in six, large in three, and not reported in two. Authors modified the interpretation of study findings based on SF-36 results in only two of the 21 discordant cases. Among 100 additional randomly selected trials not reporting any SF-36 information, at least five had collected SF-36 data but only one had analysed it.

Conclusions SF-36 measurements sometimes produce different results from those of the primary efficacy outcomes but rarely modify the overall interpretation of randomised trials. Quality of life and health related survey information should be utilised more systematically in randomised trials.


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to StumbleUpon StumbleUpon   Add to Technorati Technorati    What's this?

Relevant Articles

Effects of dietary intervention and quadriceps strengthening exercises on pain and function in overweight people with knee pain: randomised controlled trial
Claire M Jenkinson, Michael Doherty, Anthony J Avery, Anna Read, Moira A Taylor, Tracey H Sach, Paul Silcocks, and Kenneth R Muir
BMJ 2009 339: b3170. [Abstract] [Full Text] [PDF]

Patient reported outcome measures in trials
Andrew Garratt
BMJ 2009 338: a2597. [Extract] [Full Text]

Identifying outcome reporting bias in randomised trials on PubMed: review of publications and survey of authors
An-Wen Chan and Douglas G Altman
BMJ 2005 330: 753. [Abstract] [Full Text] [PDF]

Quality of life measurement: bibliographic study of patient assessed health outcome measures
Andrew Garratt, Louise Schmidt, Anne Mackintosh, and Ray Fitzpatrick
BMJ 2002 324: 1417. [Abstract] [Full Text] [PDF]

Reporting on quality of life in randomised controlled trials: bibliographic study
Caroline Sanders, Matthias Egger, Jenny Donovan, Deborah Tallon, and Stephen Frankel
BMJ 1998 317: 1191-1194. [Abstract] [Full Text] [PDF]

This article has been cited by other articles:

  • Jenkinson, C. M, Doherty, M., Avery, A. J, Read, A., Taylor, M. A, Sach, T. H, Silcocks, P., Muir, K. R (2009). Effects of dietary intervention and quadriceps strengthening exercises on pain and function in overweight people with knee pain: randomised controlled trial. BMJ 339: b3170-b3170 [Abstract] [Full text]  

Rapid Responses:

Read all Rapid Responses

Quality of Life Nonsense
Roger W Evans
bmj.com, 14 Jan 2009 [Full text]



Access jobs at BMJ Careers
Whats new online at Student 

BMJ