title: Success of randomization in a controlled contraceptive experiment.
mesh_terms: D000328:Adult; D000367:Age Factors; D001943:Breast Neoplasms / Q000139:chemically induced; D003273:Contraceptive Devices; D003276:Contraceptives, Oral / Q000009:adverse effects*; D004522:Educational Status; D005191:Family Characteristics; D005260:Female; D005833:Genital Neoplasms, Female / Q000139:chemically induced; D006801:Humans; D007182:Income; D008656:Mestranol / Q000009:adverse effects; D008722:Methods; D009641:Norethynodrel / Q000009:adverse effects; D009790:Occupations; D010298:Parity; D011336:Probability; D011446:Prospective Studies; D011647:Puerto Rico; D012107:Research Design; D013223:Statistics as Topic; D013997:Time Factors
chemical_list: D003276:Contraceptives, Oral; D009641:Norethynodrel; D008656:Mestranol