Express the confidence interval $191.6 \pm 63.1$ in interval form.

Step 1 ：Subtract 63.1 from 191.6 to get the lower limit of the interval: \(191.6 - 63.1 = 128.5\)

Step 2 ：Add 63.1 to 191.6 to get the upper limit of the interval: \(191.6 + 63.1 = 254.7\)

Step 3 ：So, the confidence interval in interval form is \(\boxed{(128.5, 254.7)}\)