Objective  To construct a multi-source data index system for early warning of respiratory infectious diseases in port cities in China based on regional epidemic characteristics of the diseases.

  Methods  The framework and elementary indicators of the index system were designated and modified through literature studies and group discussion/in depth interview among 10 senior professionals. Then, an onsite Delphi consultation was conducted among 16 domestic experts with at least 10 years′ experiences in the prevention/control, surveillance and early warning of infectious disease to assess the importance, sensitivity, availability and inclusion of the indicators. The indicators were finally selected based on the experts′ evaluation and the weight of the indicators were calculated combined with expert authority coefficients.

  Results  The scores for the experts′ academic level, judgment coefficient and familiarity are all greater than 0.7 in terms of first-class indexes. The coordination coefficient is 0.321 for the experts′ scoring on the 28 indicators of the index system. The established multi-source data comprehensive index system of early warning consists of 3 first-, 7 second- and 19 third-class indexes.

  Conclusion  For early warning of respiratory infectious diseases in port cities in China, the established multi-source data comprehensive index system is of scientificity and rationality and may provide a reference for promoting the ability of monitoring and early warning of public health emergencies.