Re: Mini percutaneous nephrolithotomy is a noninferior modality to standard percutaneous nephrolithotomy for the management of 20–40 mm renal calculi: a multicenter randomized controlled trial

The randomised trial by Zeng and co-workers [1] compared standard versus mini percutaneous nephrolithotomy (PCNL) in the management of 20–40-mm kidney stones in a collaborative effort accomplished in China. All participating surgeons worked in high-volume centres, as proved by an incredible operative time of 35–36 min (well below the 80 min previously reported by the same lead author) [2]. This noninferiority trial proved a similar stonefree rate in the two arms with comparable operative times and hospital stay (the differences of 2.2 min and <1 d are of no clinical significance), and a lower haemoglobin decrease in the mini-PCNL arm but similar complication rates.