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I ran into systematic reviews (SRs) in 1989. Dodging the draft, I had just spent 4 months on the middle ear reflex of Wistar rats, hoping to, some day, prevent human hearing damage. Instead of unraveling nature, I discovered that I was attracted more to applied science. At the Maastricht University Epidemiology department, I started reading randomised trials on acupuncture. My boss had convinced the Department of Health that reading the existing evidence was a better investment than spending at least twice the amount on the next trial that carefully ignored its predecessors' lessons. We were busy carrying out, what we called ‘criteria-based meta-analyses’ (CBMA), which we then (mis)judged superior to taking weighted averages (statistical pooling). These CBMAs boiled down to vote-counts for subgroups that differed on quality. Our basic (or biased?) expectation was that as quality goes up, the proportion of ‘positive’ studies should go down. But in the …