In multivariable regression, the ratio of disability adjusted life years found in low income regions to high income regions was a significant negative predictor of the quantity of trials (P=0.009; R=0.26 versus R=0.14 in univariable model; supplementary table C).
6 As a measure of quantity of randomised trial evidence, we used two outcomes: the number of randomised trials and the total number of participants randomised.
2 3 We found little association across disease areas between burden of disease and quantity of randomised trials, with extreme levels of variation in the ratio of trials to disability adjusted life years among diseases.
Using the Global Burden of Disease Study 2010, 6 we investigated the association between randomised trial evidence and burden of disease at a global and regional level and assessed whether variation in the quantity of randomised trials was associated with burden of disease in high and low income regions.
In the hypothetical scenario within the SD model, we compared the relative quantity of clinical trials that would be generated over time with the same amount of resources.
Thus, an effort should be made to increase the scope, quality and quantity of clinical trials within nephrology.
The significant increase in the quantity of scientific clinical trials should result in guidelines updated with more certainty and supporting evidence.
In our study, we focused only on the learning curve in five trials, so the variable obtained was the quantity of remembered words in each trial.
Additionally, reviews synthesizing comparative evidence are sparse, in large part because of the quality and quantity of head-to-head trials (Wilkinson et al 2002; Wilcock et al 2003; Jones et al 2004; Bullock et al 2005).
A trial consisted of a fixed amount of food (rabbit-chow, Nutrientes S.A., Argentina), offered 5 minutes after the crab had been introduced into the container, and left for 30 min. Unless otherwise noted, the quantity of food received in each trial was a pellet of 80 mg.
