Cardozo LD, Wise BG, Benness CJ Vaginal oestradiol for the treatment of lower urinary tract symptoms in postmenopausal women--a double-blind placebo-controlled study. J Obstet Gynaecol. 2001 Jul;21(4):383-5.
Coyne KS, Thompson CL, Lai JS, Sexton CC An overactive bladder symptom and health-related quality of life short-form: validation of the OAB-q SF. Neurourol Urodyn. 2015 Mar;34(3):255-63. doi: 10.1002/nau.22559. Epub 2014 Jan 13.
Eriksen PS, Rasmussen H Low-dose 17 beta-estradiol vaginal tablets in the treatment of atrophic vaginitis: a double-blind placebo controlled study. Eur J Obstet Gynecol Reprod Biol. 1992 Apr 21;44(2):137-44.
Nelken RS, Ozel BZ, Leegant AR, Felix JC, Mishell DR Jr Randomized trial of estradiol vaginal ring versus oral oxybutynin for the treatment of overactive bladder. Menopause. 2011 Sep;18(9):962-6. doi: 10.1097/gme.0b013e3182104977.
Tseng LH, Wang AC, Chang YL, Soong YK, Lloyd LK, Ko YJ Randomized comparison of tolterodine with vaginal estrogen cream versus tolterodine alone for the treatment of postmenopausal women with overactive bladder syndrome. Neurourol Urodyn. 2009;28(1):47-51. doi: 10.1002/nau.20583.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.