Evaluating private equity funds and feel it's all just too good to be true? You may be onto something. 

New research from the Journal of Corporate Finance shows that when private equity firms of all stripes (not just those that focus on commercial real estate) are feeling a fundraising pinch, they're more likely to massage performance metrics for companies in their portfolios. The paper—written by scholars Ranko Jelic of the University of Sussex Business School, Dan Zhou of the University of Reading, and Wasim Ahmad from the University of Birmingham—shows that regardless of a firm's reputation, PE firms may "manipulate their numbers" to give the appearance of better performance. 

"When prospective limited partners (LPs) evaluate the performance of a PE firm's latest funds, they have to rely on valuations reported by PE firms," the paper reads. "The link between PE firms' fundraising and performance evaluation is thus an area susceptible to manipulation resulting in potentially high stakes."