title: Letter: Tests for HBAg.
mesh_terms: D044383:Black People; D004586:Electrophoresis; D005069:Evaluation Studies as Topic; D005189:False Positive Reactions; D006386:Hemagglutination Tests; D006509:Hepatitis B / Q000175:diagnosis; D006511:Hepatitis B Antigens / Q000302:isolation & purification*; D006801:Humans; D007988:Liberia
chemical_list: D006511:Hepatitis B Antigens