OBJECTIVES: Predicting long-term renal outcomes in autosomal dominant polycystic kidney disease (ADPKD) is important for the identification of patients at greatest risk of progression to end stage renal disease (ESRD). The Mayo Clinic Imaging Classification of ADPKD (IC-ADPKD) stratifies progression risk (Class 1A-E, 2A-B) by cyst distribution, age and height-adjusted total kidney volume (htTKV), while the ADPKD Outcomes Model (ADPKD-OM) utilises gender, baseline TKV and baseline age. This study compares long-term renal outcome predictions using these two approaches and contrasts their respective estimates for renal decline trajectory and expected timing of ESRD onset. METHODS: The principle endpoint was time to ESRD, using profiles observed for IC-ADPKD class 1C, 1D and 1E patients in the TEMPO 3:4 clinical trial, as subjects in these classes formed the majority of the trial population.  The impact of within-class variation of TKV on time to ESRD was assessed using upper/lower boundary TKV values of the IC-ADPKD class, while holding all other profile characteristics constant.  RESULTS: IC-ADPKD predictions of renal decline fell predominantly within the 95% prediction region of the ADPKD-OM; agreement between the approaches was highest for the 1E profile. For patients in class 1C, predicted time to ESRD was 20 years (TKV 806ml lower bound) and 13 years (TKV 1,641ml upper bound) using ADPKD-OM, and 19.5 years using IC-ADPKD. For class 1D, time to ESRD was 15 and 11 years (TKV 1,223ml and 2,332ml, respectively) using ADPKD-OM, and 15.5 years using IC-ADPKD. For class 1E, time to ESRD was up to 12 years (ADPKD-OM) for TKV>1,845ml versus 11.5 years (IC-ADPKD).  CONCLUSIONS: The broad consistency of predictions obtained using IC-ADPKD and ADPKD-OM for class 1C-E profiles support their complementary use in identifying patients at highest risk of rapid progression towards ESRD.  Differences in the results across the two approaches may reflect study population and modelling methodological heterogeneity.