Study aim: Inclusion Criteria: High scores on the Health Anxiety Questionnaire; age between 18 and 55 years; and absence of physical health conditions or comorbid psychiatric disorders جExclusion Criteria: The presence of physical illnesses or comorbid psychiatric disorders; age below 18 or above 55 years; and low scores on the Health Anxiety Questionnaire. Design: A single-subject design was implemented with three participants diagnosed with health anxiety, encompassing baseline, intervention, and follow-up stages for each individual. Participants were selected through purposive sampling based on predefined inclusion and exclusion criteria. Given the nature of the single-subject design, control groups and randomization were not employed. Settings and conduct: This study was conducted at the Sehat Psychological Clinic in Pakdasht using an ABA single-subject reversal design. The research procedure comprised baseline, intervention, and follow-up phases. During the intervention phase, an integrated protocol of Schema Therapy and Metacognitive Therapy was implemented across twelve 75-minute sessions. Health anxiety, quality of life, anxiety sensitivity, and intolerance of uncertainty were assessed using their respective standardized questionnaires. Given the single-subject nature of the study and the absence of a control group, no blinding procedures were utilized.» Participants/Inclusion and exclusion criteria: Investigating the Effectiveness of an Integrated Schema and Metacognitive Therapy Protocol on Reducing Anxiety Sensitivity, Intolerance of Ambiguity, and Improving Quality of Life in Individuals with Health Anxiety” Intervention groups: An integrated Schema and Metacognitive Therapy protocol based on the Health Anxiety Model (Single-Subject Design) Main outcome variables: Health Anxiety; Anxiety Sensitivity; Intolerance of Uncertainty; Quality of Life