The Kessler Psychological Distress Scale (K10) is a self-report questionnaire designed to measure psychological distress, focusing on symptoms of anxiety and depression. Comprising 10 questions rated on a 5-point scale, it assesses symptom frequency over the past 30 days. Higher scores indicate greater distress levels. Known for its reliability and validity, the K10 is widely used in clinical and research settings to evaluate mental health and monitor treatment progress. Its simplicity and ease of use make it an effective tool for quickly assessing psychological distress.