Reporting Quality of Randomized Controlled Trials in solid organ transplantation

By: Liset Pengel | Posted on: 22nd September 2011

Last week, Liang Liu presented a paper entitled ‘Reporting Quality of Randomized Controlled Trials (RCTs) in solid organ transplantation’ at the ESOT congress which was held in Glasgow, UK.

Randomized Controlled Trials (RCTs) can provide Level 1 evidence to guide treatment. Previously, we reviewed RCTs in solid organ transplantation that were published between 2004 and 2006. The results indicated that the reporting quality of RCTs was quite poor, showing that only one-third of RCT reports were of acceptable reporting quality according to the Jadad scale. In order to find out whether there has been any improvement since our last review1 we conducted another review to evaluate the methodological quality of reports of RCTs in the solid organ transplantation published in 2007 and 2008. Additionally, we explored some factors that are associated with the reporting quality of RCTs and examined adherence to the CONSORT statement. The CONSORT statement describes criteria for reporting RCTs and is a universally accepted guideline to report clinical trials.

The quality assessment included a composite quality score assessing allocation concealment, intention to treat (ITT) analysis and the Jadad scale. The Jadad scale assesses whether the report included an adequate description of randomization, double blinding and withdrawals/drop outs. The Jadad score ranges from 0 to 5 with trials scoring 3 or greater considered as reasonable good quality trials. The quality was independently assessed by two reviewers. Disagreements were resolved by discussion or a third reviewer. In total, 206 RCTs were included in the analysis. Forty-one percent of RCTs had a Jadad score of 3 or greater and approximately one-third (35%) of the trials adequately described concealed allocation. Only 16% of reports analysed the data on the basis of ITT. Of the 206 trials, 62 trials were described as single centre trials and 105 trials as multicentre trials. For 39 trials it could not be determined whether these were single or multi centre trials. The percentage of RCTs with a Jadad score of 3 or greater was higher among multicentre trials than single centre trials (45% vs. 28%). In addition, more multicentre trials compared with single centre trials used concealed allocation (48% vs. 32%). Trials receiving commercial or commercial and non-commercial (mixed) funding were of better quality than trials receiving non-commercial funding. For example, 55% of trials funded by commercial companies and 75% of trials that received mixed funding had a Jadad score of 3 or greater versus 42% of non-commercial trials.

To review the relationship between the reporting quality and CONSORT endorsement by journals, we selected 153 RCTs in 19 journals that published at least 2 RCTs in organ transplantation. RCTs published in journals that endorse the CONSORT statement in their author instructions were on average of better quality. There was a higher number of RCTs with a Jadad score of 3 or greater, using concealed allocation and ITT analysis in journals endorsing the CONSORT statement compared with journals that did not endorse the CONSORT statement (60% vs. 28% for the Jadad score, 41% vs. 26% for allocation concealment, 28% vs. 14% for ITT, respectively).

When analysing adherence of RCT reports to the CONSORT statement we found that on average 12 out 25 CONSORT items were addressed in RCT reports. Items that were generally poorly reported were for example estimated effect sizes and its precision for primary and secondary outcomes. But also trial registration that has been a mandatory requirement by many journals was only included in 14% of reports. A flow diagram demonstrating patients flow throughout the study that has been strongly recommended by the CONSORT statement, was only included in 28% of reports.

In conclusion, the methodological quality of reports of most RCTs in organ transplantation is unsatisfactory and has not improved since 2006. Despite the development of guidelines to improve the reporting of RCTs and their endorsement by medical journal, both authors and journals show insufficient compliance with these standardised guidelines. It appears that there is a strong need to educate the transplant community about the importance of adequate methodology and reporting of RCTs. We strongly advocate the consultation of the CONSORT statement during the design and reporting of a trial. To this end, the Centre for Evidence in Transplantation and the European Society for Organ Transplantation have initiated a collaboration to help with the design and reporting of RCTs in Europe ( The collaboration hopes to improve the quality of RCTs in organ transplantation in Europe by advising investigators in the early stages of trial design and planning. In this way a strong evidence base for the best possible patient care can be built.

1 Pengel L, Barcena L and Morris PJ. Quality of reporting of randomised controlled trials in organ transplantation. Transplant International 2009; 22(4):377-84

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