Controlled clinical studies of homeopathy

•Since 1994 the published number of randomised controlled trials (RCTs) has grown by 309 records, with a doubling of the proportion that investigated individualised homeopathy.•A total of 36 condition-specific systematic reviews are identified in the current peer-review literature.•Research conclusions are limited by low quality of the original RCT evidence.•Whether homeopathic intervention differs from placebo awaits decisive answer.