3.1 Introduction
Commissioned by DOH, NIIS (National Immunization Information System) is designed by Institute for Information Industry Corp., and is developed and built up by Wistron ITS Corp..
NIIS inherits from the immunization subsystem of PHIS (Primary Health Information System), however, not like PHIS, which is a Windows application, NIIS is a web-based system with friendly user interface. As a result, it simplifies the procedures of vaccine works and provides convenience to public.
NIIS has been built up since 2002, and introduced nationwide to the 25 Health Bureaus of counties and provincial municipalities and special municipalities, 374 Health Centers of townships and county municipalities, and 600 Medical Centers.
3.2 System Architecture
The database architecture of NIIS is distributed but also centralized. Each local Health Bureaus has its own database to maintain the vaccination data within its jurisdiction. As the NIIS operation environment depicted in figure 4, work stations in Public Health Centers connect to Internet through ADSL connection, and AP servers in Public Health Bureaus and NIIS server in CDC all connect to Internet through T1 or T3 leased line.
Figure 4 NIIS Operation Environment [2]
As the NIIS operation architecture shown in figure 5, work stations in Health Centers connect directly to servers in Health Bureau whose jurisdiction it is in via ADSL, and the servers in Health Bureaus connect to Central Referral Consolidation System Server, which gets basic public information from Household Registration and Conscription Information System of Ministry of the Interior, to exchange referral data. Although the Central Database in CDC is depicted in the figure, but it is not on-line now in practice, i.e. one Health Bureau can not access the data in another Health Bureau.
Figure 5 NIIS Operation Architecture [3]
3.3 User Interface
NIIS is a Web-based system, and all steps needed in vaccination operation are fulfilled on the web pages. In this way, NIIS provides consistent and friendly use interfaces for staffs on the base level to simplify the procedure of vaccination. Following are some snapshots of the NIIS operations including login page, record page and forms of statistics.
Figure 6 Snapshots of NIIS Web-based User Interface [4]
3.4 Database Schema
Taking into consideration of database management, data independency, storage of duplicate data, accessing speed, integration and recovery, the database architecture of NIIS is designed to be distributed but also centralized. And since that the data in local database of health bureau is an accomplished fact, the local data should be fragmented and triplicate to central database, i.e. local health bureaus do not need to replicate all the data to central database, but only need to replicate chosen data according to the demand and policy of the central authority.
After considering the data construction, local database schema and the report sent to central authority by health bureaus, they made up central database schema applied to NIIS. Figure 7 and figure 8 are respectively the data model of local database in health bureaus and of central database in CDC.
Figure 7 Data Model of Local Database in Health Bureau [4]
Figure 8 Data Model of Central Database in CDC [4]
The main differences between data model of local database and of central database are as follows:
a. Local database schema has tables that store the circumstances of how the contracted medical institutions use the vaccines, e.g. BAF1, BAF2, and BAF3.
b. Local database schema has tables that store the items on yellow card, e.g. BAb1, BAB2.
c. Local database stores the basic household registry data of babies, and the investigation of side effects.
d. Central database stores data about health bureau with tables named begins with an additional letter “B”, like BBAR2, BBAP4, and etc.
3.5 System Operation
The main function of NIIS is referral-consolidation. The referral-consolidation may be needed in two circumstances: someone goes to a medical institution in or outside the area under his jurisdiction of health bureau.
Referral procedures in the area under one's jurisdiction of health bureau:
a. The direct line of health center reaches the database system of health bureau to upgrade the record data.
b. Contract medical institutions export the records into XML format, and then send the files via e-mail or discs to the health center.
c. Traditional referral clips are used for noticing the health centers of counties and cities.
Referral procedures outside the area under one's jurisdiction of health bureau:
a. If inoculation of the vaccine in the contract medical institutions, the vaccination record is transferred to local health center first.
b. Staffs of local health center establish the data and update it to the local database.
c. At 12 every night, health bureau’s system automatically sends the records not belonging to people under its jurisdiction to the central server.
d. The central server will contrast the information with database of Affairs of Household Registration, and transmit the record to the right place.
3.6 Problems
NIIS facilitates the tasks of vaccination in some degree, but there are still several deficiencies or problems we can improve or solve:
a. People still have to keep the yellow card, and if the card is gone, they can not access their vaccination records conveniently.
b. The data belongs to a Health Bureau can not be accessed by another Health Bureau, thus people can only get their vaccination records from health bureau in their domicile.
c. Between Health Centers in the same city, the yellow clip for referral is still used.
d. The systems used by Public Health Centers and by hospitals or clinics are not well integrated.