Background: The forward head posture acts as a factor that can cause various neurovascular and musculoskeletal dysfunctions. But searching for a study on quality of life for patient with forward head posture was challenging. Therefore, this study aims to find the factors that most affect the quality of life in patients with forward head posture. Objectives: The purpose of this study was to investigate the correlations between the cranio-vertebral angle (CVA), neck disability index (NDI), pain, and sternocleidomastoid (SCM) thickness of patients with forward head posture and the quality of life of the patients and to figure out important factors that affect the quality of life of the patients with forward head posture. Design: Cress-sectional study. Methods: To measure the CVA, the angle at which the visible protrusion of C7 and the ear bead were connected was measured, and the neck disorder index was evaluated using the Korean version of NDI. The degree of pain of the subject was measured using a visual-analog scale (VAS). The SCM thickness was measured using an ultrasound imaging device, and the quality of life was evaluated using the Korean version of the World Health Organization quality of life questionnaire (WHOQL-BREF). Results: A significant predictive model showing 88% explanatory power for the dependent variable was confirmed, with an appropriate regression equation being found. The factor that most affected patients' quality of life in the forward head posture was confirmed by the SCM thickness. Conclusion: When applying an intervention to improve a patient's quality of life for patient with forward head posture, an intervention method that improves the SCM thickness should be recommended.

INTRODUCTION
SUBJECTS AND METHODS
    Subjects
    Outcome Measures
    Data and Statistical Analysis
RESULTS
    Characteristics of the subjects
DISCUSSION
CONCLUSION
REFERENCES

• Minji Kang(Department of Physical Therapy, Kyungsung University, Busan, Republic of Korea)
• Kyungho Kim(Department of Physical Therapy, Kyungsung University, Busan, Republic of Korea) Corresponding author
• Jintae Han(Department of Physical Therapy, Kyungsung University, Busan, Republic of Korea)