Table 16. Number of studies where the statistical method was not reported or was unclear.

Species	Methods reported	Unclear or not reported	Unclear or not reported (%)
Mouse (n = 60) †	56	4	7
Primate (n = 76) †	74	2	3
Rat (n = 111) †	107	4	4
All (n = 247) †	237	10	4*

^†Number of studies where the statistical methods were not reported or not clear.

^*In 4% (10/247) of the studies which used statistics, it was unclear or uncertain what statistical method had been used, i.e. a p-value or statistical significance was indicated, but no other methodological details were reported.