Despite a growing awareness of race and gender in the U.S. workplace, many human resource managers say diversity efforts at smaller companies are often misunderstood or too narrowly defined, a recent study found.

In a survey of 1,400 HR professionals, roughly half said diversity programs were enabling a greater variety of people to contribute in the workplace, but often lacked a clear definition or common language to steer a company’s diversity efforts, according to the Society for Human Resource Management, an Alexandria, Va.-based organization, and the American Institute for Managing Diversity, an Atlanta, Ga.-based nonprofit think tank.

The study found that businesses with less than 100 employees were the least likely to have an official definition of diversity, while public companies and government agencies were more likely to define diversity than private non-profits and for-profits.

Overall, diversity programs tended to focus too much on race and gender, while excluding other forms of diversity, such as age, weight and socio-economic background, respondents said.

"There is a lack of discipline and understanding of what diversity means beyond race and gender or how success is being defined, or not being defined, by most corporate diversity and inclusion initiatives," said Frank McCloskey, a vice president of diversity at Atlanta, Ga.-based utility company Georgia Power who contributed to the study.