Mohsen Hajizadeh Saffar - Department of Medical physics, Faculty of Medicine, Mashhad university of medical sciences, Mashhad, Iran
Mohsen Asadinejad - Department of Medical physics, Faculty of Medicine, Mashhad university of medical sciences, Mashhad, Iran
Javad Arianmanesh - Education vice chancellor, Arman Razavi Nonprofit-Private University, Mashhad, Iran

Abstract Background: In this article Student to Staff Index was improved by implying student grades and staff academic ranks in every institute as a new Standard S. to S. Index . Also Utilized S. from S. Index was introduced for controlling and ranking the private universities.  Methods: This index uses the numbers of classes and students attended in each class, and also the grade of the staff and their teaching hours during each semester or academic year, and are presented as a descriptive study. Results: Data for calculation of these indexes were used from two universities of non-private and private using mostly wide range of specialist teachers as part-time or fee staff. The SSU Index of these two institutes for BSc students and assistant professors were respectively 1.14 and 1.33. Conclusions: The results showed that the institutions can use more staff via invited part-time and hence select those with expert knowledge and more specialization.  Utilizing Student (BSc.) to Staff (assist. Prof.) Index showed that it can be used for comparing and ranking of educational situation or qualifying the educational services in universities. 

Standard Student to Staff Index, Student/Staff Utilized Index, Student/ Staff allocation Index