Some Food for Thought

Abstract

The EVOLVE trial has several important limitations. The low statistical power hampered to find statistically significant differences in outcomes between the two groups (cinacalcet vs placebo). The elevated risk of adverse events in the Cinacalcet group influenced the high proportion of drop-out and treatment crossover. Thus, the results, which are obtained with intention-to-treat analysis, need to be interpreted with caution. As the EVOLVE trial investigated the effect of cinacalcet on cardiovascular disease in patients undergoing dialysis, it was surprising that the median patients’ age was about 55 years, which is very low compared with the age range generally observed for this population. Despite randomization, the study showed an imbalanced age distribution in the two groups. Perhaps, the authors could have used a stratified randomization according to age. In 2001 the CONSORT statement, comprising a 25-item checklist and a flow diagram, was published and focused on reporting how the trial was designed, analyzed, and interpreted; the flow diagram displays the progress of all participants through the trial. The CONSORT statement should help the readers to evaluate a randomized clinical trial.