As I explained in an edit summary this sentence attempts to summarise the information in mephedrone#UK. 'People have died after taking mephedrone' is intended to summarise "mephedrone had been alleged to be involved in 52 fatalities in the UK, but detected in only 38 of these cases". Likewise 'some deaths the media attributed to the drug were later determined to have been caused by other factors' is summarising "The death of a teenager in the UK in November 2009 was widely reported as being caused by mephedrone, but a report by the coroner concluded she had died from natural causes. In March 2010, the deaths of two teenagers in Scunthorpe were widely reported by the media to be caused by mephedrone. Toxicology reports showed the teenagers had not taken any mephedrone and had died as a result of consuming alcohol and the heroin substitute methadone". Both parts are important and should be mentioned in the lead and if you read the references you should realise that this is exceptional to mephedrone as deaths were over-reported and mis-reported by the media - comparisons with other topics are irrelevant. I agree that it is a bit weasely, but how else to you suggest that that section is summarised? WP:LEADCITE is very vague about whether citations are required and when I wrote the lead I erred on making it easier to read rather than ensuring that every fact was supported by a citation there (Wikipedia:Citation_overkill). I could easily copy the references from the main article to the lead for this sentence, but then someone will likely come along and complain that other sentences don't have citations... IMO this is a waste of time when readers could just find the relevant citations in the main body of the article.