Although promoted as a way of customizing treatment, hormone therapy does not require customization; the use of testing to determine the amount of hormones administered could result in the dose being higher than the minimum recommended level to alleviate symptoms, or the administration of unnecessary hormones to asymptomatic women may result in greater risks to the patient. In addition, analysis of the material used to promote BHT suggests that rather than basing hormone doses on saliva results, practitioners are actually adjusting the dose based on symptoms. Health practitioners customize the care of their patients on an ongoing basis by choosing the medication, dose and administration route individually, using approved medications that have a demonstrated safety record and are not subject to the errors and inconsistencies of custom-prepared combinations. Different bioidentical preparations result in mixtures with different strengths, and practitioners using compounded formulations may be unaware of the total dose of hormones their patients receive. In a 2001 test of compounded bioidentical hormone products, the FDA found that 10 out of 29 products failed their quality tests; nine out of ten failed potency tests (comparable rates for drug manufacturers were less than 2% and 0.13%, respectively) A 2006 test found potency levels ranging from 67.5% to 268.4% of the potency specified on the label; some samples were mixtures of different hormones with some being above, and others below, the specified potency. The failure of potency testing could be problematic and dangerous for progesterone products, where specific levels of progesterone are required to protect the endometrium against precancerous hyperplasia.