High certainty means that the available evidence is consistent and derived from well-designed & well-conducted studies, and as such are unlikely to be affected by future data. OK, that's fine but if you read the systematic review itself, the USPSTF could only find 4 trials, of which only one was large & of good quality showing significant benefit in lung cancer & all-cause mortality. The other 3 were small (underpowered) & did not demonstrate any benefit (insufficient duration to evaluate effectiveness). So how is the evidence consistent? And how is it that underpowered studies of insufficient duration were judged well-designed & well-conducted?
Before you jump to conclusions and rush out for your own LDCT scan, read the evidence review yourself. And ask the USPSTF (by commenting on their website) if the evidence is really that good & strong enough to support these draft recommendations?
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