Whatever benefits mergers may bring to the bottom line, they have a "pervasive, negative impact" on nearly every aspect of how employees feel about their companies, according to survey results released today by Kenexa Research Institute, a branch of Kenexa Corp., the Wayne-based employment research and software company.

Mergers cause employees to lose confidence in the company's future and prompt many to consider leaving, according to the survey of 10,000 U.S. workers. Layoffs exacerbate workers' feelings of insecurity.

To counter the risks of loss of talent and loss of engagement, companies should clearly state a tangible vision and give accurate and timely information about the merger and its effects, Jack Wiley, the institute's executive director, said in a statement.