Analysis of intra- and inter-observer error
SMI findings in pathological placentas were used to calculate the inter-observer agreement. An inter-observer error was determined by examining the four types of findings between the two examiners (NF and JH) in 22 findings. Additionally, an inspector (NF) evaluated the findings of 22 places as 4 types of findings twice at intervals, and calculated the intra-observer error.