What and where is the evidence?

Evidence for causality wide-ranging. Often circumstantial and low-grade. A plethora of publications in low impact factor (IF) or even fake journals has emerged in the 2010s. Please check IF where in doubt. After careful reevaluation, some articles may not find their way up to Pneumotox. Reporting bias and banwagon effect common. Robust evidence may come from epidemiologic studies comparing drug vs. placebo or a comparator, a distinctive or specific imaging, BAL or patholological pattern, measurement of drug levels in plasma, or a rechallenge test leading to relapse (to be done very carefully if at all). Upon request, we provide literature on drug rechallenge (as of May, 2015: 616 papers are indexes on the topic). These may be difficult to pinpoint in Pubmed. Despite abundant literature and case reports, lung reactions during treatments with DMARDs and TKI have low-to-very low evidence for causality. Careful examnination and fulfilment of diagnostic criteria is essential in each patient in whom the diagnosis is entertained (see the specific 'News')