While America’s tech firms prize themselves on their innovation, when it comes to diversity, they still lag far behind. The leadership of America’s largest tech companies are overwhelmingly white male. Under criticism, tech giants have introduced new diversity initiatives and hires. Just recently Pinterest announced its first head of diversity while Twitter announced its hire of Jeffery Siminoff as its new diversity head.

But according to research just published in the Harvard Business Review, such efforts often fail. Tessa Dover and Brenda Major, researchers from University of California, Santa Barbara, and Cheryl Kaiser from the University of Washington, reviewed previous research that showed diversity training programs often have “little positive effect” and undertook further experiments that demonstrate that programs may actually backfire, setting diversity back at companies.

In one experiment, Kaiser, Major, and Dover ran a hiring simulation with white male subjects in the position of job applicants. Half of the applicants receive materials mentioning pro-diversity values while the other half received materials without such a message. The subjects who read the pro-diversity materials “expected more unfair treatment and discrimination against whites,” the HBR article noted. Cardiovascular monitoring showed they were stressed, and observers ranked these subjects as performing worse in their interviews than the other group. It’s also worth noting that even white male subjects who said they supported diversity initiatives had these reactions.

“Groups that typically occupy positions of power may feel alienated and vulnerable when their company claims to value diversity,” the authors wrote. “This may be one explanation for the lackluster success of most diversity management attempts: when people feel threatened, they may resist efforts to make the workplace more inclusive.”

Another study the three researchers conducted with another team found that that the presence of a diversity policy can lead whites and men, in general, to assume that a work environment was fair even when there was evidence to the contrary. In another set of experiments reported in this study, minorities were found to be unpersuaded by pro-diversity messages. “Participants from ethnic minorities viewed a pro-diversity company as no more inclusive, no better to work for, and no less likely to discriminate against minorities than a company without a pro-diversity stance,” the HBR article authors wrote.

In the Harvard Business Review article, the authors also note other research has shown attempts to “moderate managerial bias through diversity training and diversity evaluations are least effective at increasing the share of white women, black women, and black men in management.”

This body of research, the academics say, should make companies question the value of their diversity initiatives. Last year Intel intc , Google goog , and Apple aapl , to name a few, pledged to spend vast sums in extensive diversity programs. “In terms of return on investment, companies are putting a lot more into diversity programs and diversity management than what they’re getting out, at least in terms of increasing representation,” Dover told Fortune.

The answer isn’t to abandon diversity programs. Instead, Dover says, for diversity initiatives to be effective, the company must hold people accountable for results. Without metrics and concrete goals, there is little ability to change, she says.

Indeed, if you look at findings of these studies — the reaction of white males to pro-diversity messages and the distrust by minorities — pro-diversity rhetoric alone “may be making a large segment of their workforce vulnerable to discrimination and worried about their own experiences at the firm,” Dover told Fortune. “If you’re going to say you value diversity, you need policies in place that support diversity, otherwise you make people [in the majority] feel vulnerable and likely less supportive of the cause.”