Your Sept. 2 editorial "Student Deadbeats" misses the major point of the loan default "problem."

You contend that a significant part of the problem involves proprietary vocational schools. High default rates are not a proprietary school issue. Most recent research from the largest state guaranteed loan agency reveals that it is the population served, not the school, that largely determines the default rate. High default rates exist in any postsecondary institution that serves large numbers of high-risk students. Community colleges, historically black colleges, four-year public institutions, such as the University of the District of Columbia, and any other institution that serves low-income students will have a higher default rate. The fact that four-year institutions serve a much lower percentage of low-income or high-risk students perhaps is more of an indictment of those institutions than it is a reason to criticize proprietary schools, community colleges and others that do serve the neediest population.

The influence of an educational institution on defaults is questionable. Our experience shows that a single corporation owning many private career institutions throughout the country will have vastly different default rates even though the policies, procedures and educational programs are identical. The only variable that is different is the income level of the families from which the students come. Many proprietary institutions have default rates under 5 percent; these are primarily located in middle-and upper-income areas.

Your contention that "defaults are an epidemic threatening to become a habit" misses the point. Compared with other consumer credit, federal loan programs are very successful given the lack of credit-worthiness tests and lack of loan repayment experience of the post-secondary student. Federal policy makers should anticipate some losses to the program given the types of students who are required to borrow in order to attend college. Where loans made up only 17 percent of a student's aid package just seven years ago, they are now approximately one-half of a student's aid package. High-risk students are now heavily dependent upon loans to pay for their education.

Twenty-eight changes designed to reduce defaults were made to the guaranteed student loan portion of the recently reauthorized Higher Education Act. We are optimistic that these changes, in concert with voluntary default prevention programs such as ours, will lead to default reductions.

Private vocational education does "perform a valuable service" and will continue to do so. Reckless observations and simple scenarios about this sector of postsecondary education will have the most damaging effect not on the institutions but on high-risk students. Social policy in federal programs must be designed to remedy the complex problems facing this nation. The training of all of our people to fill potential jobs is the issue. We hope that policy makers will agree.

Stephen J. Blair and Jerry W. Miller

Stephen J. Blair is executive director of the National Association of Trade and Technical Schools. Jerry W. Miller is president of the Association of Independent Colleges and Schools.