1. Ministry of Health and Welfare (KR). Medical service act. Act No. 14438. 2016. 12. 20.
2. National Health Insurance Service (KR). National Health Insurance integrated nursing care program manual. Wonju: National Health Insurance Service;2016.
3. Cho SH, Kim YS, Yeon KN, You SJ, Lee ID. Effects of increasing nurse staffing on missed nursing care. Int Nurs Rev. 2015; 62(2):267–274. DOI:
10.1111/inr.12173.
4. Coffman JM, Seago JA, Spetz J. Minimum nurse-to-patient ratios in acute care hospitals in California. Health Aff (Millwood). 2002; 21(5):53–64. DOI:
10.1377/hlthaff.21.5.53.
6. Royal College of Nursing. Mandatory nurse staffing levels. . London: Royal College of Nursing;2012.
7. National Institute for Health and Care Excellence (GB). Safe staffing for nursing in adult inpatient wards in acute hospitals [Internet]. updated July 2014. cited 2017 January 12. Available from:
https://www.nice.org.uk/guidance/sg1.
8. American Nurses Association. Principles for nurse staffing. 2nd ed. Silver Spring, Maryland: American Nurses Association;2012.
9. Giovannetti P. Understanding patient classification systems. J Nurs Adm. 1979; 9(2):4–9.
10. Song KJ, Kim EH, Yoo CS, Park HO, Park KO. Development of KPCS (Korean Patient Classification System for Nurses) based on nursing needs. J Korean Clin Nurs Res. 2009; 15(1):5–17.
11. Song KJ, Kim EH, Yoo CS, Park HA, Song MS, Park KO. Verification of reliability and validity of KPCS-1 and estimation of nursing time conversion index. J Korean Clin Nurs Res. 2010; 16(2):127–140.
12. Kim SS, Chae GS, Kim KN, Park KO, Seong SM. Survey on nursing care delivery systems of university affiliated hospitals in Korea. J Korean Clin Nurs Res. 2010; 16(1):167–175.
13. Lankshear AJ, Sheldon TA, Maynard A. Nurse staffing and healthcare outcomes: A systematic review of the international research evidence. ANS Adv Nurs Sci. 2005; 28(2):163–174.
14. Bae SH, Fabry D. Assessing the relationships between nurse work hours/overtime and nurse and patient outcomes: Systematic literature review. Nurs Outlook. 2014; 62(2):138–156. DOI:
10.1016/j.outlook.2013.10.009.
15. Olds DM, Clarke SP. The effect of work hours on adverse events and errors in health care. J Safety Res. 2010; 41(2):153–162. DOI:
10.1016/j.jsr.2010.02.002.
16. Hendrich A, Chow MP, Skierczynski BA, Lu Z. A 36-hospital time and motion study: How do medical-surgical nurses spend their time? Perm J. 2008; 12(3):25–34.
17. Westbrook JI, Duffield C, Li L, Creswick NJ. How much time do nurses have for patients? A longitudinal study quantifying hospital nurses' patterns of task time distribution and interactions with health professionals. BMC Health Serv Res. 2011; 11:319. DOI:
10.1186/1472-6963-11-319.