Poor experiment design, accidental contamination, and inadequate data analysis are all major research problems we’ve pointed out on this blog. Now, a new study published in PLOS Biology estimates that problematic research that isn’t easily reproduced may be costing $28 billion per year. Of course, that doesn’t mean all those studies were complete wastes. Some studies included in that figure did find valid results, but for various reasons (such as confusing methodology) aren’t easily reproduced. Read more.