Who delays retirement past 65 - and why?

People who delay retirement tend to consider work one of the most meaningful parts of life and to believe that others think more highly of people who work, a University of Southern California gerontologist reports.

Carolyn Paul, a senior staff associate at USC's Ethel Percy Andrus Gerontology Center, bases her findings about older people's work habits and attitudes on a recent analysis of the Retirement History Survey, a 10-year study conducted from 1969 to 1979 by the Social Security Administration.

At the beginning of the study, participants ranged in age from 58 to 63. They were interviewed every two years about their attitudes toward work and retirement, their current employment, their income, and other topics.

In her analysis of the data, Paul focused on two questions:

* Who delays retirement past age 65 - and why?

* Why do some people return to work after they've retired?

She found that married men were very likely to delay retirement past age 65. Those who did were likely to be business managers or professional individuals. Women who delayed retirement, on the other hand, tended to work in clerical or service jobs.

To her surprise, Carolyn Paul found a high rate of employment among never-married persons, too. She had initially hypothesized that never-married persons, without the financial obligations of a family, might be a group likely to take early retirement and enjoy leisure activities.

In light of the findings, she now suggests that never-married persons may tend to delay retirement because work serves as a substitute for the family they don't have. ''They may receive a type of social gratification from work that others (with families) may not,'' she says.

Ms. Paul found that the employment rate among separated, divorced, and widowed persons in the survey was lower than anticipated. She speculates that, at least in the case of the women, they may be receiving financial help from a deceased spouse's pension benefits.

When participants were asked why they delayed retirement, 86 percent said they consider work one of the most meaningful parts of life. Nearly as many - 84 percent - said they believe others think more highly of people who work.

Those who delayed retirement often had no definite retirement plans. ''Nearly half of the men indicated they had no plans to quit working,'' Ms. Paul found. ''And 40 percent of the women had no retirement plans.''

In the sample of 7,974 persons, 241 returned to work after retiring. ''Of the 241,'' Paul reports, ''only 26 were women.

''The conclusion seems to be that as women retire, they tend to stay retired - more so than men,'' she says.

''The men in the sample who returned to work tended to have adequate pensions ,'' Ms. Paul reports. ''So men may return to work mainly for instrinsic reasons or personal rewards, not because of pure financial necessity.''