Complex sentence: Brief treatment due to managed care may be difficult, as individuals diagnosed with DID may have unusually difficulties in trusting their therapist or fear rejection and lengthy, regular contact (weekly or biweekly) is more common.
Split into simpler sentences: Brief treatment due to managed care may be difficult, as individuals diagnosed with DID may have unusual difficulties in trusting their therapist or fear rejection. Regular contact (weekly or biweekly) is more common.