Warning on asthma trials
Clinical trials of asthma treatments are wide open to commercial manipulation, the influential Drug and Therapeutics Bulletin warns.
A lack of agreed standards for effectiveness means drug companies can 'pick and choose' outcomes that suit their purposes, says the evidence-based review journal.
Editor Dr Ike Iheanacho said: 'Clinical trials vary greatly in the types of measures they use to assess the effects of asthma drugs, and this makes it difficult to compare different trials or to assess whether new treatments offer a genuine benefit for patients.
'Symptoms can be assessed in terms of severity and frequency, but there is no universally accepted standard for scoring them, and different studies record different sets of symptoms and use different scales.'
An analysis in the March edition of the DTB cautioned that comparing data from different trials can be difficult.
Dr Iheanacho warned it was also important to be cautious of over-interpretation of second-ary endpoint results. 'These may just add to the confusion.'