I published a paper some years ago now that examined regulatory impact statements in Australia and NZ, and their relative effectiveness. The reference is:
Adrian Sawyer, "Regulatory Impact Statements and Accountability: Recent Australasian Evidence" (2008) 11(1) Journal of Australian Taxation, 42-107. It is available online.
I am not entirely sure whether this is what you are looking for when you mention impact factors, which may be you are looking to journal rankings and impact factors. If so, then you may wish to look at tools such as Scopus.
Hi Murat, this is pretty interesting idea for research - my suggestion: if you want to establish quantitative model or other methodology for number of countries, the only thing that coming in my mind is Regulatory Impact Assessment (RIA) - prepared in the first time by WB and OECD: https://www.oecd.org/gov/regulatory-policy/44789472.pdf ; http://www.oecd.org/gov/regulatory-policy/ria.htm. This icould give some base for creating something for more then one country. At this moment we are implementing project regarding RIA in Macedonia (and often discuss for this issue) --so I think that your idea will be relevant for number of countries.