Results There were 1390 negative crossmatch and 130 positive crossmatch cases. There was no difference in overall graft survival, although early survival rates were lower in the positive crossmatch group, with the maximum difference at 6 months: 0.76 (95% confidence interval, 0.74-0.78) for a negative crossmatch versus 0.68 (95% confidence interval, 0.61-0.77) for a positive crossmatch. These d...

This note analyzes the asymptotic distribution for instrumental variables regression for panel data when the available instruments are weak. We show that consistency can be established in panel data.

Difference-in-differences with matching is a popular method to measure the impact of an intervention in health as well as social sciences. This method requires baseline data, i.e., data before interventions, which are not always available in reality. Instead, panel data with two time periods are often collected after interventions begin. In this paper, a simple matching method is proposed to me...