A comparison of CIM and FMA estimates for the slope of a linear dose response (ERR/Gy) for outcomes generated from a Poisson model (CR: 95% CI coverage rate, LER: left error rate, RER: right error rate, LCI: length of 95% CIs, ARB: absolute relative bias, RUL: relative upper limit).

CR, RER, and LER were defined as the percentage of times the true value of the slope of the dose response was inside the CI, below the lower limit, and above the upper limit, respectively. ARB was calculated as the absolute difference between the estimated value of the slope of a linear dose response and the pre-determined true value (β = 3) divided by the true value of the slope.