Believe it or not, the National Association of Home Builders maintains a website on mold.
The site is called NAHB Household Mold Resource Center
No one out there knows more about remediation than a qualified contractor. (No one knows less than an unqualified one.) The site discusses significant information about mold, conditions, prevention, mediation. Understandably, they don’t focus much on mold testing.
It does make sense that an association of contractors might gloss over the importance of testing. Mold testing can provide a legal record of mold conditions, mold which might have come into being because of shoddy workmanship or materials. So if the homeowner has repairs made, but does not keep a complete record–including testing, photographic proof, etc–the homeowner might find themselves unable to bring a case that they might have otherwise, given proper record-keeping.
However, the National Association of Home Builders can and will recommend “a qualified laboratory, technician or industrial hygienist.”
Testing also can help doctors pin down whether a mycotoxin originated from home or workplace, or even simplify making a diagnosis, especially if a particular allergen or obscure toxin is involved.