Listen now (22 mins) | Estimating the size of the file drawer problem
A suggestion about this point: "In some cases, the biases are small. One study (Dickersin 1993) of trials approved for funding by the NIH found 98% of positive trial outcomes were published, but only 85% of negative results were (i.e., positive results were 15% more likely to be published). "
I think that the real salient point is that non-positive findings are 7.5x more likely not to be published. 85 => 98 is de minimis in this context.