length of service and commitment of nurses in hospitals of social security organization (sso) in tehran

background: a nurse’s commitment is the most important factor that influences her performance and depends on other variables. the purpose of this research was to study the relationship between length of service of the nurses with the amount of occupational commitment and organizational commitment. methods: from winter 2012 to spring 2013, 266 nurses were chosen in selected hospitals of social security organization (sso). these nurses were randomly categorized into six different classes of service records including < 5, 5-9, 10-14, 15-19, 20-24, and 25-29 years. the length of service is related to the organizational, occupational, affective, continuance, and normative commitment. the data were collected and analyzed. results: generally 84% of the responders were women and the rest were men of which 95% had a bachelor’s degree and the rest had higher academic degrees. the length of service in 81% of nurses was <15 years and 19% were higher than 15 years. significant correlation were seen between continuance and occupational commitments and length of service (r=0.23, p=0.04 and r=-0.26, p=0.02, respectively). there were not any significant differences regarding organizational, affective and normative commitments (p=0.12, p=0.33, p=0.47, respectively). conclusion: the results show that the length of service was related to continuance and occupational commitment. so pre-retirement of the nurses after 20 years of work can result in an increase in average commitment of employees.