Extended Abstract
1. Objectives
The purpose of this study was to present a 5-factor model of life motivation for aged people in a physical environment and examine the correlations between its 5 factors. These factors can interact with each other; however, each can be separately measured and their impact on the motivation of elderly’s lives can be examined independently. 
This study also investigated related design and spatial factors to provide solutions for increasing this group’s motivation for life; then, we evaluated the correlations between these factors. Eventually, some strategies were presented for the architectural design of nursing homes to increase the morale of their residents. Moreover, the relationship between man-made and physical environments and their impact on the motivation of aged people were discussed.
2. Methods and Materials
In this study, various steps were taken to achieve the required data. First, based on the literature and asked questions, a table of goals/contents was prepared. The characteristics of each system identified in previous studies were included in table columns. The formulated questions were provided to 11 psychologists and architects from the different universities of the country; they were asked: “Does the content cover the goal?”. Based on their answers, some contents were deleted and some new contents added to the table. In the next step, a 41-item questionnaire rated on a Likert-type scale (very high, high, moderate, low, and very low) was designed based on the prepared contents (Table 1).
A sample size of 131 was calculated based on the Cochran formula and considering an error rate of 0.08 and a 92% confidence interval. We ensured the validity of the questions and evaluated the scale’s internal consistency by measuring Cronbach’s alpha coefficient. Then, 150 questionnaires were distributed separately and based on a non-random quota sampling method among the elderly living in 15 privately owned nursing homes in Shemiranat, Tehran Province, Iran. The questionnaires were completed by the researcher through an interview with samples. The collected data were analyzed in SPSS using descriptive statistics and performing the Pearson’s correlation coefficient.
3. Results
According to the research findings, the increase in the elderly’s motivation for life is related to the physical design of their living environment. In this regard, 5 general factors were identified, including environmental educability and persuasiveness, environmental comfort and desirability, peace and quiet, the perceived sense of ownership, and similarity to home space. Each of them had a relation to some sub-factors related to physical design. The factor “environmental educability and persuasiveness” had a correlation with space for learning art, readability, the recognizability of interior spaces, and the compatibility of internal spaces with physical disabilities. The factor “environmental comfort and desirability” was correlated with lighting, ventilation, a 2- to 3-person living space, the hygiene of indoor public spaces, easy access to all spaces and equipment, and the existence of green space. 
The factor “peace and quiet” had a correlation with noise pollution, the existence of shade trees outside the building, the existence of outdoor furniture (e.g. benches and trash cans), interior design with privacy and good view, the existence of fountain/waterfall/pond, and the existence of outdoor spaces for relaxation. The factor “the perceived sense of ownership” was correlated with the sense of ownership in the own bedroom or having a personal room, the quality of the bedroom, tendency to be under care and control, the existence of recreational and entertainment spaces (e.g. chess and card game rooms), and kitchen size. 
The factor “similarity to home space” was correlated with the quality of living and guest rooms, the size of lateral spaces (i.e. showers, sinks, and toilets), the quality of lateral spaces, the changeability of the interior furniture design, and neighborhood and proximity to other residents. Based on the study findings, physical design is a factor influencing the motivation for life in elderly people living in nursing homes. The dependence or non-dependence of aged people as a disturbing variable had been neglected and was revealed at the end of the study. Thus, it is strongly suggested to pay special attention to it in future research. Other overlooked aspect of this study was the existence of religious spaces in nursing homes which inspires retrieving memories and imaginations, like furniture and its arrangement. Moreover, considering noise and odor in the design of nursing homes should be assessed in the future.
4. Conclusion
According to the research findings, the architectural design directly affects improving the motivation for life in the elderly. Thus, it is impossible to separate the aspect of physical and spatial design in aged people’s nursing homes from the psychological aspects. One of the research limitations was the inability of the elderly to complete the questionnaires and difficulty in communicating with them. This issue was solved by asking questions from them and those emotionally connected to them. Moreover, the lack of cooperation of some of the nursing homes caused many interruptions in the investigation process. It is recommended for the future research to explore the effect of the identified factors on the independent variable, separately; by comparing these criteria in different nursing homes, they can provide the most suitable and optimal accommodation for seniors (individual or collective, institutional or non-institutional).

Ethical Considerations
Compliance with ethical guidelines
All ethical principles were considered in this article. The participants were informed about the purpose of the research and its implementation stages; They were also assured about the confidentiality of their information; Moreover, They were allowed to leave the study whenever they wish, and if desired, the results of the research would be available to them. 
Funding
The present paper was extracted from the PhD thesis of the first author, Department of Architecture, School of Architecture & Urban Design Engineering, Shahid Rajaei Teacher Training University.
Authors contributions
All authors contributed in designing and preparing this study.
Conflict of interest
The authors declared no conflict of interest.
Acknowledgments
The authors thank the Welfare Organization of Tehran province for their cooperation in introducing researchers to the Shemiranat Rehabilitation Section and facilitating the issuance of permits to visit nursing homes. We also thank the senior managers of the private sector, especially the nursing homes of Arad, Noraste, Parsayan, Kimia and Parham.