Five-step definition.
Beckett
H
H
D018865:Dental Research / Q000379:methods*; D003813:Dentistry / Q000592:standards*; D019317:Evidence-Based Medicine / Q000379:methods*; D005260:Female; D006801:Humans; D010518:Periodontitis / Q000150:complications; D011247:Pregnancy; D047928:Premature Birth / Q000209:etiology; D009626:Terminology as Topic