This research investigates the potential impact on design creativity of using parametric CAD methodologies (BIM design and algorithmic design) in the early design stage/process of hospital buildings. The research design consists of comparative studies between parametric and nonparametric CAD methods, and the study of creativity, which focuses on two domains: process creativity and product creativity. Besides, the study extends the creativity research to the area of reviewing design behaviour and design cognition to investigate the advantage and disadvantage of using CAD to improve, or hinder, the performance of the problem solver throughout the design process. The selection of research methodologies was designed to support evidence-based objective research findings. Dual methodologies were employed: 1. a retrospective questionnaire evaluation of design performance and 2. a computer-based protocol analysis of the on-going design process.

The first part of the research findings went through a questionnaire survey and the data was mined, processed and statistically analysed using the SPSS package. Two seminal works were used and adopted as a bench mark criteria for assessing and determining creativity during the design process: that of Torrance’s test for creative thinking (TTCT) for measuring creativity as a ‘process’ and that of Amabile for appraising creativity as a ‘product’. The result indicates that parametric CAD, especially the algorithmic CAD method, significantly supports the creativity process during the initial hospital ideation process and is significantly different from the other two CAD methods in the production of idea numbers, variety, and uniqueness. While judging the product creativity of the hospital building design, the parametric CAD architects (the algorithmic CAD and the BIM design) both reported that the CAD working environment helped a lot in this regard. On the one hand, the BIM group replace reported with either that CAD supported them in their idea development, spatial functional coordination, and design message delivery. On the other hand, the algorithmic CAD group recounted that the CAD method enhanced the elaboration of their ideas and novel thinking.
In the design cognition review, the computer-based protocol analysis was applied to investigate the ongoing design process with different CAD groups. It was found that when using the algorithmic CAD process, the participants could construct to a large extent reconstruct their long-term memory (LTM) in the design cognition process, which has ultimately assisted the architects’ design learning and helped them focus more on the creation of the design strategy rather than repeatedly using the same examples. Thus, the algorithmic CAD process through suggesting different mathematical interpretation was found to reinforce cognitive design reasoning and offering varied idea segmentation (considered as a measure for divergent thinking, an essential indicator for creativity). It is believed that the CAD method can create a flexible with systematic and associative ideation activity. With this advantage of the algorithmic CAD program, this PhD study also discovered a parameter-based real-time design representation (3D models) and visible design content/script (node diagrams) so architects can instantly revise their design and update their cognitive processes to perform a better design synthesis and evaluate their proposed ideas.
This PhD research will contribute to current architectural design knowledge and future hospital design research and will help to develop a better environment in healthcare design practice as well as in the areas of architectural CAD teaching and Its promotion within the curriculum.