Nineteen Washington area men and women, including a pharmacist, a college teacher, a secretary in the U.S. Attorney's Office and a prison guard at Lorton, were indicted by a federal grand jury yesterday in a computer check-cashing scheme involving phony medical payments from Group Hospitalization Inc.

A total of $125,000 in fraudulent checks were issued and cashed at local liquor stores and banks by friends and relatives of GHI employes and others who recruited them to submit false psychiatric claims. The claims were submitted under Blue Cross-Blue Shield plans processed by Group Health, according to the indictment issued by the grand jury in Baltimore.

Under the scheme, the perpetrators allegedly split the proceeds with the others, all of whom were Blue Cross-Blue Shield subscribers, and promised to destroy the evidence. However, postal inspectors were called in after an internal GHI audit uncovered the fraudulent payments, U.S. Postal Inspector Tom McClure said.

As many as 18 checks totaling $19,513 were cashed by one of those indicted, McClure said.

All those indicted were charged with mail fraud and conspiracy to defraud. Mail fraud carries a prison term of up to five years and a $1,000 fine. The conspiracy charge is punishable by one year in prison and a $10,000 fine.

The GHI employes indicted were Fred Dale Coombs, 30, of Oxon Hill, who worked in the supplemental claims division until August 1981; Stephanie Adell Mathis, 23, of 2551 Elvans Rd. SE, a mail clerk in the division, and Ronald B. Dixon, 33, of Clinton, a supervisor there.

Also indicted were Leonard Anderson, 30, and Valerie Griggs, 25, both of 3455 25th St. SE, and Tyree Anderson, 50, Leonard's father and a prison guard at Lorton.

Also, Alphonso Bigger, of 5842 Oregon Ave. NW, owner of the Brookland College Pharmacy; Rose Frederick, 36, of Suitland, secretary to the director of compliance, Commerce Department; Stanley Griffin, 37, of 4951 Sargent Rd. NE, a photographer at the University of the District of Columbia; Nesaline Griffin Freeman, 31, of 3403A Mount Pleasant St. NW, a teacher at UDC, and Shirley Whittle Barksdale, 32, of 3342 Mount Pleasant St. NW, a secretary in the District Department of Education.

Also, Thelma Freeman, 28, of 813 Elder St. NW, a clerk at the D.C. Department of Human Resources; Linda Gordon, 23, of 4524 Eads St. NE, an Army Department secretary; William Truesdale, 35, a laborer at the Library of Congress; Donna Gates, 27, of Upper Marlboro, until recently a secretary in the civil division of the U.S. Attorney's Office here; Patricia Cullum, 29, of 622 Franklin St. NE, a D.C. schools supply technician; Michael Kirby, 32, of Lanham, a former Government Printing Office employe; Calvin Corbitt, 29, of 219 Seaton Pl. NE, a GPO worker, and Raymond Harper, 43, a D.C. government trash collector.