Consider the following output for a polynomial regression of degree 3 with 3 treatment groups and 4 timepoints: Value Std.Error t-value p-value (Intercept) 1.483686 0.0503941 29.44167 0.0000 factor(trt)2 0.701066 0.0712680 9.83704 0.0000 factor(trt)3 1.228633 0.0712680 17.23962 0.0000 poly(time, degree = 3)1 3.308072 0.3103926 10.65770 0.0000 poly(time, degree = 3)2 -14.398808 0.1523560 -94.50768 0.0000 poly(time, degree = 3)3 -7.007665 0.0907406 -77.22743 0.0000 factor(trt)2:poly(time, degree = 3)1 3.228969 0.4389614 7.35593 0.0000 factor(trt)3:poly(time, degree = 3)1 6.394605 0.4389614 14.56758 0.0000 factor(trt)2:poly(time, degree = 3)2 -1.273551 0.2154639 -5.91074 0.0000 factor(trt)3:poly(time, degree = 3)2 -2.061363 0.2154639 -9.56709 0.0000 factor(trt)2:poly(time, degree = 3)3 -0.186509 0.1283266 -2.23266 0.1461 factor(trt)3:poly(time, degree = 3)3 -0.983514 0.1283266 -7.66414 0.0000