The way you respond to your boss's tirades or a stubborn co-worker may say more about your capacity to succeed in the workplace than cognitive intelligence, new research shows.

An employee's ability to effectively identify, interpret, and react to colleagues' emotions as well as their own determines their emotional intelligence, or EQ, which experts consider a key factor in professional success.

A recent study by Multi-Health Systems, a North Tonawanda, N.Y.-based company that provides psychological assessments for the workplace, examined the impact of stress on an employee's emotional intelligence. Researchers found that when employees are stressed, their emotional intelligence is hindered and workplace problems can result. Out of 1,014 employees surveyed, 53 percent said stress hurts their relationships with co-workers. Another 47 percent said that stress often affects their ability to make decisions in the workplace.

"One of the things that happens when you're under stress is you're not paying attention to your impact on other people," said Steven Stein, a psychologist and CEO at Multi-Health Systems. "Stress impacts your ability to do well at work and can impact the way you react to other people around you such as your supervisors."

According to Stein, emotional intelligence is also essential to career advancement, even more so than IQ. In addition to good interpersonal skills, employees with high emotional intelligence are successful at adapting to change, maintaining a positive mood, and empathizing with others. "It's hard to be a really good leader without high emotional intelligence," Stein said.

The study found that when employees' emotional intelligence is hindered, they are less likely to get ahead in the workplace. One in three respondents said that stress prevented them from being recognized for their contributions at work, and 27 percent believe that stress has prevented them from advancing in their career. However, 55 percent of respondents said they were not aware of the impact emotional intelligence has on their professional success.

The good news for employees, according to Stein, is that unlike IQ, a person can boost their emotional intelligence by applying the right skills in the workplace. Stein suggests practicing empathy. "Think about what's going on with people around you, don't just react to them when they say or do something, but figure out where they are coming from," Stein says. Additionally, finding social support at work -- a close friend that you can check in with and confide in -- is another way that employees can minimize stress and boost emotional intelligence, Stein added.

The study also has important implications for business owners, who can play a role in improving the emotional well-being of their employees. Stein has found that business owners who encourage a more social atmosphere in the workplace have happier and more productive employees. He also cautions employers about putting unreasonable expectations on employees. "Employers really have to think about how they're treating their staff and the amount of work they are giving employees," Stein said.