The drug-extract ratio (DEV) is strictly speaking the "native" drug-extract ratio (DEV native) declared in drug extracts. It specifies the initial amount of drug used for the preparation of a certain amount of extract. For a dried extract with a DEV of for example 10:1, it means that 1 part of dried extract of 10 parts of drug was collected and then used for the preparation of 10g of dry dried extract for 100g of drug. With the dosage of the herbal medicine, this number can always be calculated on the amount of drugs used for this purpose. This means that various dried extracts of a drug can be compared in their quality and conclusions can be drawn as to the enrichment of the ingredients. Dried extracts have depending on the used plant part a DEV of 5 to about 50:1, fluid extracts (liquid extracts) have a DEV of 1:1 to 1:2, thick extracts (viscous extracts) for example 3-6:1, tinctures and other alcoholic extracts usually 1:7 to 1:9 or 1:4 to 1:4.5, depending on the amount of alcohol used for extraction of the drug.