How can I get the lower and upper confidence limits of a best-fit parameter into Excel as separate values, rather than a single text string?

In the nonlinear regression results, Prism reports the confidence interval of each parameter. When you export or paste the confidence interval, Excel gets it as a single string "123.45 to 234.56". There is no way to instruct Prism to report the two individual values separately, rather than as one text string. But you can write an formula in Excel that will separate the two. The function first needs to find a smaller string with just the value you want, and then convert that text string to a value. To extract the lower limit, use this Excel formula:

=Value(LEFT(A2,FIND(" to",A2,1)))

To extract the upper limit, use this Excel formula:

=Value(RIGHT(A2,LEN(A2) - (FIND(" to",A2) +3)))

These formulas assume the text string is in cell A2, but they are easy to adjust for other locations.

Beginning with release 4.03 and 4.0c, Prism will let you choose to report the lower and upper confidence limits separately, avoiding the need for the fancy Excel formulae described above. Contact us about beta testing.