Im not sure why you would do this. To run a reliable analysis, ANOVA would require all the values to calculate within and between group varaiation. Without this, I would be very sceptikal of your resulting F value.
because its a fitted value after a non linear regression of the raw data. the raw has no relationship to this value that i can enter into spss, it is not just a 'mean' of the data. it is calculated and optimised elsewhere as a point on the curve that fits the data.
ANOVA calculates the variation from the mean and sem from the data anyway and i see no real reason why i cant skip the step and enter it directly.