Keyes' original research questioned.
D000293:Adolescent; D000328:Adult; D001419:Bacteria / Q000302:isolation & purification; D002648:Child; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010510:Periodontal Diseases / Q000382:microbiology / Q000628:therapy*; D012107:Research Design