Authors' reply.

We thank Dr. Alavian for his comments on our study. To address each of his points:

Firstly, the level of knowledge regarding hepatitis B virus (HBV) was indeed lower than we had expected [1]. Our surrogate for measuring knowledge included several questions where respondents to our survey were asked to interpret hepatitis B serologies. The results show that 78.8-94% of trainees and 80-94% of program directors answered correctly. This may be due to the low prevalence of HBV in the United States as compared to certain other countries. We agree that the low response rate is a limitation. However, we believe we captured a diverse group of respondents, across geography, experience, and practice setting.

Secondly, immigration from endemic areas has certainly changed the landscape of HBV in the US. While it is a disease important for all healthcare workers to be aware of, it is especially important for those healthcare workers to screen HBV in specific populations. It is very encouraging to see that almost all of the obstetricians and gynecologists who were surveyed do report screening for HBV in pregnant patients. With respect to knowledge and comfort with HBV, when analyzing data from different regions in the US (not reported in our paper), we were not able to find significant differences among practitioners. This may be due to the low response rate, as we would expect those in coastal cities to have encountered more patients with HBV, given the higher percentage of immigrants in those cities.

Lastly, it is customary in the US for healthcare workers to be tested for hepatitis B surface antibody titers prior to starting employment. If the titers are low or undetectable, the healthcare worker would be required to receive either a booster or the entire series of hepatitis B vaccination.

Overall, our study provided a look at the practice and knowledge of HBV among obstetricians and gynecologists in the US. It would be very interesting to expand it to include practitioners around the world.