Without a change of order the sentence would be very confusing and unbalanced. There would be 39 words before the main verb 'is needed' and only eight after it. Moreover, there would be 38 words between the semantic marker and the main verb which it is supposed to modify:
Because
the authorities that decide on entitlement to services are usually unaware of the extent and significance of the disabilities in Asperger's Syndrome (AS), active participation on the part of the clinician, together with parents and possibly an advocate, is needed to forcefully pursue the patient's eligibility for services.Click here to continue.