Recently Zhan et al1 reported that nonsteroidal anti-inflammatory drugs (NSAIDs) are not as harmful as previously thought and even are potentially beneficial for preventing progression to dialysis in patients with chronic kidney disease (CKD). These results contrast with most clinical observations, and we have concerns about the authors' statistical methodology. First, NSAID users could have more rapid CKD progression but no higher dialysis incidence if the observation period is not long enough.