Introduction: Thesis commonly reflects student's research interests, which are formed in the university education courses. Formation problem in thesis is one of the most important subjects in these research documents. Limitations and situations govern in research scope causes author (researcher) to limited framework of topic as problem base in his or her research. Investigation of thesis content and their subject trend can help each auditor to identify students' interests, and make a good guidance for correct programming in future.

Method: Content analysis method is used in this research, and record unit are "subjects" or "thesis subjects". The bases for subject definition are areas extracted from American National Library of Medical Subject Headings. Three subject heading groups were used "Information Science", "Administration", and "Health Care Economics and Organizations".

Results: Theses are distributed to three main subject groups according content analysis. "Information Science" with 89 theses had the most number of thesis, due to thesis distribution of two majors "medical record" and "medical library & information science" in this subject. "Health Services Administration" with 67 theses topics in second. "Health Care Economics" with 41 theses topics was in third degree 13 theses were not included in any of thesis subject groups, and finally each lied in a subheading group.

Conclusions: The results show that some subjects were more regarding than others. "Medical library & information science", "staff management", "cost & cost analysis" in have the most numbers due to: advisor specialization, lessons headings, and disregarding or no knowledge of modern and up to date subjects.

Introduction: Addiction, which has recently attracted the attention of researchers, is a serious problem worldwide. The growth of relevant literature contributes to a better understanding of this problem and improves the interaction between executive organizations and academic institutions. It is important to identify the active subject areas within this field and to explore the topics which are more frequently discussed in research documents using techniques of subject clustering analysis. The main purpose of this paper is to do a content analysis of papers related to addiction in PubMed through hierarchical clustering.

Methods: This is a descriptive and applied research analyzing the content of literature through hierarchical clustering. To obtain data, a search for the keyword “Addiction” as a Mesh term in PubMed was conducted, on 21/04/2015, for papers published in 1991-2014. Descriptors were extracted from the papers retrieved, and data were analyzed using Ravar Matrix and SPSS ₂₀.

Results: According to the findings, the size of scientific literature in the area of addiction increased during the period under the study. Subject clustering led to the identification of most widely used topics, including substance related disorders, addictions to the Internet, gambling, smoking, etc.

Conclusion: Through thematic analysis of documents (descriptors), a wide range of dispersed topics were grouped into six clusters.  The members of each cluster had common characteristics and they were structurally interrelated. The main concern of researchers, as indicated by descriptors in these six clusters, were on psychological aspects of the issue.