SPSS: Meta-analysis on "prevalence" of angular measurements

Dear all,

we are currently conducting a meta-analysis. We have three diffrent treatment procedures to correct a malalignment of the great toe. We would love to calculate the "prevalence" of the initial angulare mesurements (how cruccet were they) for each of the three groups separatley. Is this possible in SPSS and if so how to do it.

Thanks for your help!