The phrase "although various methods have" is correct and usable in written English.
It can be used to introduce a contrast or exception in a discussion about different methods or approaches.
Example: "Although various methods have been proposed to solve the problem, none have proven to be entirely effective."
Alternatives: "Even though different methods have" or "While several methods have".
Although various methods have been proposed, there are still problems hindering its practical applications.
Although various methods have been developed for ligating DNA molecules or targeted mutagenesis of plasmids, each has its limitations.
Although various methods have been used, the management of controlled ovarian hyperstimulation is not easy in poor responders.
Although various methods have shown to be more or less successful, they often are very energy-consuming, require extreme conditions or lead to by-product formation with unknown adverse effects [27].
Although various methods have been reported for the synthesis of aminochromenes [12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27], however, some of these methods involve the use of expensive reagents, toxic solvents, tedious workup, long reaction times and harsh reaction conditions.
Although various methods have been reported to inactivate soft and hard tissue, it is still difficult to inactivate tissue rapidly without damaging the extracellular matrix (ECM) [ 6].
Furthermore, although various methods had been used to acquire the primary data we needed, the OS of three studies was still absent; it would inevitably result in evaluability bias.
Although these various methods have some advantages for the synthesis of polyhydroquinolines, they have some drawbacks such as harsh reaction conditions, use of expensive catalysts or reagents, tedious work-up procedures, sensitivity to water and toxicity.
Various methods have been tried.
Various methods have been developed to control mosquitoes.
Various methods have been proposed [ 11].
