Đó là một huyền thoại, và nó tan chảy dưới áp lực. Vì vậy, vấn đề này trở thành: thay đổi giá trị đường cơ sở là gì và làm thế nào để chúng tôi kết hợp các thay đổi đó vào cơ sở dữ liệu? Có một số phương pháp tiếp cận hợp lý và thực tế, chúng tôi chia sẻ với bạn, ở đây. | 260 MEASURING THE VALUE OF WORK Issue 3 What If the Project Workscope Changes Does It Invalidate the EVA We have already discussed at length the issues associated with change control and scope management. Wherever we have mentioned EVA we talked about the importance of maintaining a valid baseline. We talk about freezing the baseline. Then we give multiple illustrations of when and how it is okay to modify these data. Before you accuse us of being inconsistent and confusing we need to review a few points that were made earlier. These were There must be a baseline plan for the EVA methods to work. There are legitimate conditions under which the baseline can be changed. No changes to the baseline should be made without a reason for the change a set of details about the change and an audit trail for all changes. There must be a formal structured and heeded system for change control and scope management. Which all lead us to ask If the project workscope changes does it invalidate the EVA The simple answer is no it does not. However in order to maintain a valid baseline for EVA we need to integrate the change control practices with the EVA practices. All that you need to know to do this was discussed in Chapter . Rather than repeat these illustrations here we direct your attention to Chapter Part 3. Issue 4 How Do I Manage the Baseline for Projects Where the Baseline Changes with Each Phase of the Project We continue now to look at one more issue regarding maintaining a valid baseline for EVA when the defined workscope keeps changing. In this instance we address the common situation of a progressively expanding definition of the work at each phase of a development project. We described such projects in Part 4 of Chapter . We direct your attention to that material to see how it is possible to maintain an EVA baseline as each phase further defines the work and schedule. This is indeed a challenging situation. But it is one that can be fully addressed and dealt .