Fig. 1.

Referral sources and common symptoms in UDN applications . 1A: Not Accepted individuals were significantly more likely to be referred by their primary care physicians than healthcare providers in all other disciplines combined (FET, p < 0.001). 1B: The four most often reported symptoms in the Not Accepted group are reported significantly less frequently in the Accepted group (χ2 = 15.43, p < 0.01). 1C: Referral letters authored by primary care physicians mentioned significantly more subjective symptoms (t = 6.2, p < 0.001) and fewer objective findings (t = − 4.15, p < 0.001) than letters authored by other providers regardless of application outcome