Causes (1) Variation (1) Thresholds (Doorsills) (1) Terms and phrases (1) Surveys (1) Terms and phrases (1) World health (1) Time (1) Symptoms (1) Speeches, addresses, etc (1) Reason (1) Questionnaires (1) Public health (1) Psychometrics (1) Numerals (1) Narration (Rhetoric) (1) Morale (1) Depression, Mental (1) Anxiety (1) Anxiety disorders (1) Use studies (1) Use studies (1) Mathematical models (1) Names (1) Origin (1) Health (1) Students (1) Origen (1) Encuestas (1) Salud (1)