Context: Promoting the quality of learning and teaching processes at the tertiary level, including distance education, has been considered as a strategic approach by policy makers in higher education, throughout the world. For this reason a reliable and comprehensive evaluation mechanism can play an important role in assessing the current situation and identifying the needs and problems from one hand and identifying the most important appraisal indicators on the other hand. This study aimed at critically reviewing the literature and theoretical frameworks of previous relevant researches to highlight the most important components and indicators that must be applied in appraising distance education. Methods:Due to the importance of using the findings of previous studies as a foundation for extracting the most important appraisal indicators, 42 national and international research studies relevant to the evaluation of distance education were selected and analyzed, which were published in refereed journals during year 2006 to 2015. The eligibility criteria for selecting these studies were their relevance to any aspect of distance education. For this reason and in order to identify indicators, the content of these studies were analyzed based on the open coding method. Later on, all findings were categorized, outlined, and summarized according to the main components, which may form a comprehensive evaluation system for distance education at the higher education level. Results:The findings of this meta-synthesis showed that pedagogical knowledge, technology, learning organization, educator, learner, learning content, teaching models and strategies, time, place and space were the most important components of a comprehensive appraisal system that should be considered in evaluating distance education systems and its mechanisms and processes, continuously. Conclusions:The rise of distance education in Iran's higher education sector has urged that new comprehensive evaluation system has to be applied as a platform for improving and guaranteeing the quality of learning and teaching processes, curriculum and learning materials, and even the way by which these institutions are managed. Consequently, it is important to be assured that our policies and practices in higher distance education are on the right pathway. Therefore, based on the theoretical frameworks and studies performed before, the outcome of this meta-synthesis however, has highlighted some critical components which are necessary to be taken into account if this system has to be evaluated comprehensively.

The high education state need to determine the indicators to evaluating their trainers function that one of the basic problems in universities is lack of indicators of effective lecturers. One of the most important methods to determine these indicators is public poll students. This study is done due to determining the indicators of effective lecturers in student's viewpoint of Payame Noor University in Kurdistan province at 20010-2011 academic years. This study is done in the measuring method and it is statistical society for all of Payame Noor University students in Kordestan province that 360 people among Sanandaj, Saghez and Ghorveh College are collected as sample using of cluster-sampling method. Data collecting tools was inquiries that were made by researcher. The various methods such as descriptive statistic were used to analyze the data. In student's opinion the indicators of teaching methods, communication, knowledge-seeking, personal characteristic have allocated the most important indicators' of effective lecturers to itself. Regarding to achieve results, it seems