Yolanda Jimenez, Gloria Cristina Masache and Helman Gomez roamed the corridors of an N Street NW apartment building yesterday afternoon, clipboards and pens in hand.

Their mission was to learn more about a rapidly growing population that community activists and researchers worry has been overlooked in city data: the District's Latino residents.

"We hope some good things come of this," said Gomez, one of 18 data collectors attempting to paint a demographic portrait of the city's Latino community through an in-depth health survey.

Coordinators of the survey hope to learn more about a range of health issues for Latino men, women and children, including health care coverage, eating habits, alcohol consumption, prenatal care, sexually transmitted diseases and heart problems.

"The objective here is to look at the health disparities in Washington, D.C., between Latinos and other groups," said Eugenio Arene, executive director of the Council of Latino Agencies, the lead organization behind the survey.

The council is a nonprofit coalition representing 40 social service and health groups that serve the District's Hispanic community. Their partners in the survey project, called the Latino Health Care Collaborative, include the D.C. Department of Health, George Washington University and three clinics.

Hispanic residents in the District numbered about 45,000 in the 2000 Census, or nearly 8 percent of the city's population. Social service providers and community activists believe that the figure is much larger.

It is a population that faces many obstacles. A report released last year by the Council of Latino Agencies showed that Latino children in the city were more likely to drop out of school than non-Latino youngsters. A 2002 report found that 38 percent of D.C. Latinos younger than 65 lacked health insurance, compared with 18 percent of all city residents. Latino per-capita income was 39 percent less than the D.C. average, according to census numbers cited by the council.

Getting comprehensive information on the community has been challenging for researchers, because of the language barrier as well as fear among some Latinos that strangers asking personal questions could be immigration officials, Arene said.

"The District-based health data for Latinos is deplorable," said Heather McClure, policy and research director for the council. Until last year, she said, death certificates in the city listed only black, white or other for the deceased.

Since the survey began in February, data collectors have knocked on doors seven days a week. They have conducted 774 interviews in Wards 1, 2 and 4, where a majority of Latinos reside. Interviews are kept confidential, and each participant is given a $20 international calling card. Blocks of Latino households were located using census data.

The findings, scheduled to be released in the fall, will be used as a research and policymaking tool for government agencies, community groups and the general public, McClure said.

Yesterday, Jimenez, Masache and Gomez conducted some of the project's final interviews. Inside the apartment building near Logan Circle, they were turned down a few times by those who were too busy or appeared too fearful to agree to an interview. But after about an hour of knocking on doors, the workers sat down with three Spanish-speaking residents, from Mexico and El Salvador.

Jimenez and Gomez, both of whom are originally from Colombia, and Masache, from Ecuador, have interviewed about 150 people since February. It has not been easy, they said. Some were open to answering personal questions about their health, they said, but others declined to take part for a variety of reasons, such as their immigration status or unease about letting strangers in their homes in high-crime areas. And still others in more middle-class neighborhoods told them, in Spanish, that they were not Hispanic but American and refused to participate.

But having data collectors who know the language and the culture has helped in getting people to open up more than they might in a telephone survey with an English-only speaker, Arene said. "The fact that your own community is interviewing you makes a difference," he said.

Yolanda Jimenez, left, and Gloria Cristina Masache are two of 18 data collectors knocking on D.C. apartment doors for the Latino health survey. The findings are to be released in the fall.