... referral) maydepend on the nature of the condition, whether the refer-ral is for reasons of diagnosis and/or treatment, the pref-erence of the provider, and the relationship between the providers. ... evi-dence of efficacy/effectiveness for a given condition suchas musculoskeletal chest pain, that the path of referral forchest pain will depend on the nature of the condition and the urgency of the ... situation, that the point of referral maydepend on the familiarity or relationship between the providers, and that the nature of the referral (e.g., amountand type of information accompanying the referral)...