Diagnostic Tools in Sleep Medicine.

This article presents a structured, clinically grounded approach to the diagnosis of sleep disorders. Key conceptual distinctions are clarified to support accurate symptom characterization and avoid diagnostic misclassification. Validated screening instruments are reviewed. Objective diagnostic modalities are discussed. The role of the physical examination and targeted biomarkers is emphasized as a means of enhancing diagnostic precision in selected patients. Through integration of clinical data, subjective assessments, and objective measures, the experienced clinician can accurately diagnose and manage common sleep disorders including insomnia, hypersomnolence disorders, obstructive sleep apnea, and circadian rhythm sleep-wake disorders while delivering individualized, patient-centered care.