Project management methodologies. What documented and statistically meaningful evidence is there that project management methodologies actually increase project success rates however that "success" may be defined?

Q #19 (nineteen): http://www.maxwideman.com/musings/issues.htm

Project management methodologies. What documented and statistically meaningful evidence is there that project management methodologies actually increase project success rates however that "success" may be defined?

5000 words max, excluding references, turn-it-in pass.  APA style

Table of Contents/ Executive Summary/Rationale/ Introduction/ Methodology/Literature Review /Results/ Conclusion /Bibliography

Tips in addition to references that the Tutor must find:

Project Management has been practiced since ancient Egyptian times, and was further developed by the Chinese, Greeks, Romans, etc. So, there is a long history associated with it, along with many, many studies of its benefits.

Start with the Blog titled "The Complete Collection of Project Management Statistics" in 2015 by Emily Bonnie. This is a significant, current work in this area with great sources or references for further research.

In 2013, a Brazilian named Leandro Alves Patah wrote an article called "The Impact of Project Management Investments in Project Success". This article is more scientific and includes a very extensive number of sources.

Also in 2013, KPMG New Zealand published a White Paper titled "Project Management Survey Report" which is a nice contribution on this subject.

Finally, PMI has published many White Papers over the years on this subject including:

The High Cost of Low Performance (2014)

Capturing the Value of Project Management (2015)

Organizational Project Management - Why Build & Improve (2015)

What it really boils down to is that there are many lessons learned and documented over the last 100+ years, which have resulted in Best Practices, Standards, and Methodologies. We can always choose to ignore that wisdom and reinvent the wheel by the seat of our pants, at our own peril. But most intelligent business and IT managers today recognize the value of appyling tried & true principles & processes to improve overall project performance, consistency, predictability, reliability, and effectiveness.