Week 9

 

Four possible approaches for changing from one information system to another. These approaches can be helpful for the  Health Centres to change from the existing manual system to the new Child Health information System (CHIS).

Direct Cutover : This  approach needs the system to change from the old system to the new system when the new system becomes operational. However,  this is the least expensive approach method because the IT department has to operate and maintain only one system at a time. This is considered as the risky method, because  even after testing and training some problems may arise when the new system becomes operational.

Companies often choose this method to implement commercial software packages because they feel that the commercial packages has less risk of total system failure. Most of the times, direct cutover is only used by the organizations for non critical situations.

 

Parallel Operation :  This method requires that both the old and the new information systems operates completely for the specified period. In this method, data is used as input for both the systems and the output is generated by the new system when compared with the output form the old system.  The main advantage of this operation is that it involves lower risk. If the new system doesn’t work  the old system can be used as a back-up until the changes are made to the new system.

Parallel operation does have some disadvantages and it’s also a costly changeover method. Because in this method, both the old and the new system will be in full operation and the company has to pay for both the systems during the parallel period.  This system is not practical if the operating system cannot support both the systems .

 

Pilot Operation :  This method requires implementing the complete new system at a selected location of the company. In this method the new system is installed only in one specific department of an organization and is called a pilot site. During this testing period the old system continues to work in other departments except the one where the new system is installed. After the new system is proved successful, it is installed in other departments. Therefore, pilot operation is a combination of parallel operation and direct cut-over methods.

By implementing the new system this way, reduces the risk of system failure and is also less expensive than a parallel operation.

 

Phased Operation : This changeover method allows us to implement the new system in different stages or modules. For example, instead of implementing a new manufacturing system at once we can install the materials management subsystem and then the production control subsystem and then the job cost subsystem. We can implement any of the subsystems by using any of the changeover methods.

However, systems analysts sometimes confuse phased and pilot operation methods. These two methods combine both direct cutover and the parallel operation methods to reduce the risks and costs. One of the advantages of this approach is that the risk of the errors or failures is limited to the implemented module.  If a new production control subsystem fails  to operate then it may not affect the new subsystem or the existing control subsystem.

 This system is less expensive than the full parallel operation because it requires that we have to work with only one part of the system at a time.

 

Recommendations  for CHIS : It is recommended that the phased operation changeover method must be used for the CHIS as this will allow the new system to be implemented in different sub-stages  and it is also less expensive than the changeover methods  as it is required that we have to work with only one part of the system at a time.