Copyright © 2016 American College of Occupational and Environmental Medicine. Unauthorized reproduction of this article is prohibited Development and Validity Testing of the Worksite Health Index: An Assessment Tool to Help and Improve Korean Employees’ Health-Related Outcome Young Ho Yun, MD, PhD, Jin Ah Sim, MS, Ye Jin Lim, MA, Cheol Il Lim, PhD, Sung-Choon Kang, PhD, Joon-Ho Kang, PhD, Jun Dong Park, MD, PhD, and Dong Young Noh, MD, PhD Objectives: The objective of this study was to develop the Worksite Health Index (WHI) and validate its psychometric properties. Methods: The devel- opment of the WHI questionnaire included item generation, item construc- tion, and field testing. To assess the instrument’s reliability and validity, we recruited 30 different Korean worksites. Results: We developed the WHI questionnaire of 136 items categorized into five domains, namely Gover- nance and Infrastructure, Need Assessment and Planning, Health Prevention and Promotion Program, Occupational Safety, and Monitoring and Feed- back. All WHI domains demonstrated a high reliability with good internal consistency. The total WHI scores differentiated worksite groups effectively according to firm size. Each domain was associated significantly with employees’ health status, absence, and financial outcome. Conclusions: The The WHI can assess comprehensive worksite health programs. This tool is publicly available for addressing the growing need for worksite health programs. T he world is facing a health epidemic driven largely by the increasing occurrence chronic diseases, which could lead to large productivity losses and unsustainable medical costs. 1–6 Improved identification and management of modifiable risk factors such as tobacco use, poor diet, physical inactivity, excess body weight, hyperglycemia, and high blood pressure can minimize the development of chronic disease. In an effort to improve health outcomes and lower medical costs, greater emphasis has been placed recently on disease prevention and health promotion. 3,7 The health care system is undergoing a paradigm shift toward early identification and management of risk factors to avoid a future burdened with insurmountable health care costs. 3 Within the worksites, this dramatic shift occurred because of the primary motivations of the return on investment (ROI) and reduction of health care expenses of the employers, and with the consensus that the workplace is an ideal environment for initiating health screenings. 3 This strategy has shown promising results for early detection, prevention, and management of established risk factors of noncommunicable diseases. 3,8,9 The effectiveness of health screening on each of the behavioral and biometric measures was stronger when screening was followed by offers of compre- hensive worksite health and wellness programs such as the Assess- ment of Health Risks with Feedback, 3,10 Blue Cross – Blue Shield of Kansas City, 11 which was initiated to impact working culture and to improve workers’ health, and Healthy Heart program of the New York State Department of Health. 13,14 Moreover, by implementing science-based strategies documented to effectively improve health outcomes, the impact of a comprehensive worksite health promotion program on employee health may be considerable. Moreover, the effects of such health promotion programs are reportedly sustain- able and clinically meaningful. 1 Faced with rising costs, employers are interested in workplace health and wellness programs to improve employee health and reduce economic losses from poor health and worker absenteeism. 12 The Korean government adopted the Seoul Declaration on Safety and Health at Work and the World Health Organization (WHO) suggested global level of action plans to enhance the level of health and safety in the workplace and reduce health costs at the worksite. 13,14 Many employers are turning to workplace health programs to help employees adopt healthier lifestyles, improve productivity, and lower their risk of developing costly chronic diseases. 15 For example, a 1% reduction in the risk factors has been shown to save $83 to $103, much of which could be passed on to employers in the form of reduced premiums. In addition, meta-analysis of currently available studies on the costs and savings associated with such programs indicated that a well-designed comprehensive worksite health and wellness program provided ROI by improving health and reducing costs, which justified the employers’ upfront investment. 1,3,7 The Centers for Disease Control and Prevention (CDC) began the National Healthy Worksite Program designed to assist employers in implementing science- and practice-based health strategies that promote good health, reduce chronic illness and disability, and improve worker productivity; all of these factors contribute to improving an employers’ competitiveness in the marketplace. 15 The key to a successful worksite wellness program is the creation of a culture and environment that supports health and wellness with the ability to evaluate the structure and activities directed at changing its policies, facilities, and services collectively to assure that the program is implemented effectively and achieving its intended health and financial outcomes. 9,16,17 Recently, the CDC developed (and updated in 2014) the CDC Worksite Health Score Card (HSC), a self-assessment survey instru- ment, in collaboration with the Emory University Institute for Health and Productivity Studies. 18 The HSC includes questions about key evidence-based interventions as part of a comprehensive worksite health program and helps employers assess their health promotion programs, identify gaps, and prioritize high-impact interventions to prevent chronic conditions. 1 In this report, we describe the development and validation of a new Worksite Health Index (WHI) in combination with an employee survey as a part of Social Contribution for Health in line with the CDC HSC. 6 From the Department of Biomedical Science (Dr Yun, Ms Sim, and Ms Lim); Cancer Research Institute, Seoul National University College of Medicine (Drs Yun, Noh); Institute of Health Policy and Management, Seoul National University College of Medicine and Hospital (Dr Yun); Department of Educational Technology, Seoul National University College of Education (Dr Lim); Department of Business Administration, Seoul National University Business School (Dr Kang); Department of Physical Education, Seoul National University College of Education (Dr Kang); Department of Pediatrics (Dr Park); Department of Surgery, Seoul National University College of Medicine and Hospital (Dr Noh), Republic of Korea. This study was supported by grants from the R&D Program for Biomedical Research Center, Seoul National University Hospital, Seoul, Korea (grant number 0620144000); the Ministry of Culture, Sports and Tourism, Seoul, Korea (grant number 80020140005); and the R&D Program for National Research Foundation of Korea (20100028631). The authors have declared no conflicts of interest. Address correspondence to: Young Ho Yun, MD, PhD, Department of Biomedical Science, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea (lawyun@snu.ac.kr) Copyright ß 2016 American College of Occupational and Environmental Medicine DOI: 10.1097/JOM.0000000000000731 JOEM  Volume 58, Number 6, June 2016 623 ORIGINAL ARTICLE