The Application of Meta-analysis Technique in Identifying Effective Dimensions and Criteria in Designing the Facades of Historical Axes with an Emphasis on the Mental Image of Citizens

The mental image is an accumulated image that reflects the time and place identities; it is the aspect of the city perceived by a large number of citizens and has a special value on the society’s self-esteem and culture. The urban facade is also a unique manifestation of the city that emerges in the deep perceptual layers of the environment. The mental image in the urban facade has a cumulative cause that reflects the spatiotemporal characteristics of the background and context, which can be understood by a large number of people. These two factors have an undeniable effect on each other, the main purpose of which is to improve the perceptual and physical qualities of the urban landscape, which is clearly visible in historical situations. The main purpose of this research is to explain the identification of effective dimensions and criteria in designing the facade of historical axes with an emphasis on the mental image of citizens. In order to fulfill the purpose of the study, the meta-analysis method was used. Searches were done manually and based on related keywords (e.g., mental image, urban facade, and historical axes) and the type of hypotheses raised, 121 studies were identified with different titles related to the structure of the research being studied. In the first stage, according to the established protocol and standards, some articles were removed from the research process. Finally, 40 studies were excluded from the research process, and 81 scientific articles (Persian and English) related to the topic, which were in the period of 1390-1400 and 2012-2021, were selected as the statistical population of the research.  Scopus and Elsevier databases were used for studies and access to related research in the Latin field, and for the Persian information database, Iranian scientific documents (irandoc), the country's publications database (Magiran), elmnet, Civilica, and Google Scholar were used. The data collection method was based on the PRISMA protocol, which is the standard for meta-analysis studies. The results show that most of the articles were reviewed only in the name of descriptive-analytical and did not provide a detailed structural framework for this issue and the volume of samples was very low, which caused a high error rate in the theoretical output of the studies. In the theoretical foundation section, more than 39% of articles lacked basic theory.