[5] She earned money for her college expenses by working as a stenographer at The Post-Standard, a Syracuse newspaper and by giving readings with touring Lyceum companies.

[1] Roos's professional theatrical debut occurred in May 1921 in a performance of The Harlequinade at the Neighborhood Playhouse in New York City.

[8] Her other Broadway credits included Peer Gynt (1960), Orpheus Descending (1957), Joan of Lorraine (1946), War President (1944), The Trojan Women (1941), Abe Lincoln in Illinois (1938), Daughters of Atreus (1936), Black Widow (1936), Panic (1935), Tight Britches (1934), Life Begins (1932), Little Women (1931), Schoolgirl (1930), Veneer (1929), Grand Street Follies [1928], Lovers and Enemies (1927), Makropoulos Secret (1926), Loggerheads (1925),Grand Street Follies [1924], This Fine-Pretty World (1923), The Player Queen (1923), The Green Ring (1922), and The Idle Inn (1921).

[9] She starred as Elizabeth Stover in "The House", written by Art Wallace, a 30-minute episode of the mystery anthology series The Web, broadcast on live television airing on August 29, 1954.

In 1955–1957, she had originally played the role of compassionate Althea Raven, the first mother in-law of heroine Vanessa Dale.