Note * Studies are very important. However, the paradigm of biomedicine does not easily fit the paradigm of Chinese Medicine.
Medical practice encompasses all facets of humanity though controlled trials don't often reflect this. By approaching subjects in a multi-method/multidisciplinary fashion as is more the norm in social sciences, brings rich data, instead of merely stasticially valid data as is provided by controlled trials.
Hundreds of years of clinical observation and records in China do not comply with modern scientific methodologies and are therefore considered anecdotal. They are still a vast reference with far more benefit then may be suggested by a lack of scientific proof. It's worth considering this if your condition is not mentioned as having been proven scientifically to have benefitted from acupuncture treatment.
Studies are continuing to be published in numerous medical journals.