Almost half of large nonprofit groups make insider deals with board members, and one-third of those deals occur without the prior approval of other board members, according to a new study by the Urban Institute. The study, which is described in a report released on Monday, "Nonprofit Governance in the United States: Findings on Performance and Accountability From the First National Representative Study," also found that many groups fail to attract ethnically diverse leaders. Half the boards that participated in the study had only white members, none of whom were Hispanic. The study comes at a time when many institutions are revisiting their board structures in the wake of recent governance scandals in both the corporate and nonprofit sectors. While the boards of some universities and charitable organizations have followed Wall Street's lead and tightened rules in response to the Sarbanes-Oxley Act of 2002, which requires stricter governance of public companies, many nonprofit organizations have been slow to take steps to improve their internal controls.