Purpose: To evaluate the methodological quality of randomized controlled trials (RCTs) published in Intensive Care Medicine from 2001 to 2010, and to compare it with a previous review of RCTs published from 1975 to 2000.
Methods: We assessed the quality of reporting of randomization, blinding and participant flow, both individually and combined within the Jadad scale, and compared them with findings from our previous review. For RCTs published from 2001 to 2010, we also evaluated the frequency of distorted finding presentation (spin) and inflated predicted treatment effect (delta inflation).
Results: In the 221 RCTs from 2001 to 2010, the sample size was significantly larger than in the older series, and there was a higher proportion of studies with negative findings. Reporting of the rationale for sample size estimation and allocation concealment increased significantly, but reporting of other important individual methodological components did not change substantially compared with the previous period and remained low. Among RCTs from 2001 to 2010, a spin strategy was used in 69 of 111 RCTs with statistically negative results, while delta inflation was present in 7 of 11 RCTs evaluating survival as a primary outcome. Papers with higher Jadad scores were cited more often than the others.
Conclusions: Quality of reporting of RCTs published in Intensive Care Medicine has only partly improved over time, and spin and delta bias are of frequent occurrence. There is a need for stronger adherence to CONSORT recommendations, with special emphasis on accurate description of randomization and blindness, and correct reporting of statistically non-significant results.