Model of scientific reasoning.
Melzack
R
R
D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D002908:Chronic Disease; D006801:Humans; D010146:Pain / Q000188:drug therapy* / Q000523:psychology; D019966:Substance-Related Disorders / Q000209:etiology
D000701:Analgesics, Opioid