Not the OP, but one of the organisations I work for publishes best practice guidelines for diagnostic tests for various rare genetic disorders in an attempt to

Not the OP, but one of the organisations I work for publishes best practice guidelines for diagnostic tests for various rare genetic disorders in an attempt to avoid this issue. However the process takes between 1 and 2 years and starts from identifying a group of leading clinicians and academics who specialise in that condition who are willing to write the guidelines (on their own time, for free). They then do a literature search to gather any relevant material and at the same time put out a call for submissions to clinicians around the world asking them to contribute. A (usually virtual) conference is then held and the writing begins. Over the next few months a set of draft guidelines are produced and then put out for comment. After a period for feedback a second draft is produced and sent out again. A consensus building exercise is then conducted (aka another mini conference involving the guideline writers and others) and the guidelines finalised according to the consensus. They're then published in a peer reviewed journal. As you can imagine this takes time and money and all of it is sponsored by a not for profit EQA organisation, with no pharma companies involved (since they're who provide the tests and that's a massive conflict of interest). As a result the org only manages to produce two or three guidelines a year, when really they'd like to be able to produce a dozen or more. And they also need to be reviewed at regular intervals which while slightly less long winded is still long winded. Really this is the sort of thing that is a prime candidate for being sponsored by government, and sometimes it is, but since these are rare conditions the cost / benefit analysis is not always favourable.