请问Fisher's two-stage procedure和The omnibus test 是什么意思啊，用spss怎么做出来啊。

原文献中写道“ Given that there were three levels of the grouping variable, Fisher's two-stage procedure was used to control the familywise error rate at 0.05; multiple comparison tests were assessed at ɑ= .05 only if an initial omnibus test was statistically significant ”，其中Fisher's two-stage procedure和omnibus test 是什么啊，用spss怎么做啊，

然后，后面结果部分原文献也写道“The omnibus test of an overall group effect was not statistically significant for time to solution, F(2, 28.19)=2.31, p =.134. Omnibus tests using trimming and bootstrapping could not be calculated for number of errors and number of correct answers, possibly due to floor and ceiling effects respectively on these variates; however, omnibus tests based on ordinary least squares estimators were not statistically significant number of errors: F(2, 42.04) =1.83, p= .173; number of correct answers: F(2, 44.49) =0.38, p= .687”。同样其中的The omnibus test是什么意思啊，spss中怎么做啊。