The study has several limitations. First of all, the surveyed hospitals were restricted to four city and provinces, even some types of hospitals were rare (the number of the surveyed community health center and emergency center was just one, respectively), therefore, the results may not fully represent the PHE capacity of all hospitals in China. Secondly, because of self-report method there may be a respondent reporting bias. The inclusion of official documents from respective Health Bureaus, for example, may have encouraged respondents to complete survey but have also been interpreted as an official assessment of capacity leading some hospital representatives to overestimate PHE capacity. Thirdly, only quantitative data were collected to measure certain capacities of PHE preparedness. Most questions required a "yes" "no" or "unknown" answer which restricts the collated data to these three categories. Finally, this data set is not complete as some hospitals did not respond and others had to be excluded on the basis of incomplete answers or for ineligibility for hospital classification. To a certain extent, this loss of respondents caused a loss of information.