Anxiety, SeparationRefusal to ParticipateStudent DropoutsAnxietyAnxiety DisordersChild BehaviorSchoolsPhobic DisordersTic DisordersPanic DisorderTreatment RefusalDiagnostic and Statistical Manual of Mental DisordersPsychiatric Status Rating ScalesRefusal to TreatMental DisordersComorbiditySchool NursingSchools, MedicalSchool Health ServicesAge Factors