The Kidney Disease Outcomes Quality Initiative (KDOQI) recommended target for adequacy for dialysis with 2/week schedules was to give a standard Kt/V of at least 2.1. This is hard to do unless residual urea clearance is >2.0 mL/min and preferably higher. Data from the US suggests that 2/week dialysis should not be given to anuric patients, but data from China and Korea finds that outcome is not worse with a 2/week schedule, even when standard Kt/V is <2.0. So, how to restrict 2/week dialysis is an unsettled question.