The independent parliamentary body found that the Infrastructure and Projects Authority (IPA) lacks details on the implementation and outcome of projects from the Government Major Projects Portfolio.
NAO head Sir Amyas Morse said: “The Infrastructure and Projects Authority is clearly contributing much-needed project management and evaluation techniques to the mammoth programme of major projects run by government.
“We believe it could drive greater improvement if it adopted a clearer method of measuring the benefits of these projects, and tougher discipline over the terms on which projects are included, or more to the point, excluded from its oversight.”
The body has recommended that the IPA exert more control when projects leave the portfolio, improve data collection on benefits and request all projects to have an up-to-date business case, while government departments should deliver a statement at project closure to evaluate achievements.
“Recent improvements are welcome but there is still a need for the [IPA] to develop its oversight at exit and for departments to monitor and evaluate projects and their outcomes more consistently, so that performance improves and maximum value is derived from projects,” the report concluded.
Earlier this year, IPA CEO Tony Meggs said the agency had “recruited somebody” to specifically gather more data on the effectiveness of PFI projects.