For thin film resistors, meeting AEC-Q200 requirements includes passing the biased humidity test 85°C/85%RH. But what does passing the test mean for the devices in real-life applications? Furthermore, is it possible to predict the worst case drifts of resistors under load and environmental conditions from the 85/85 data? To answer these and other test-related questions, a long-time comparison study was made at the standard test conditions, extended conditions to 4000 h at 10% and 30% of maximum operating power, and at 70°C/90%RH and 90°C/40%RH. This paper shows the results of this comparison study, whose data points enable us to give answers about acceleration factors of applied temperatures.