Evidence-based design ‘evolving fast’

The search for continuous improvement in healthcare services has stimulated different levels of discussion about how to improve the design of healthcare facilities. Improvements have been achieved at different levels by adopting numerous solutions. However there is uncertainty related to what is best in different contexts. This necessitates an evidence base to be established to better inform decisions in the healthcare domain. Another issue raising governmental and academic debate relates to whether or not substantial investments in the public service realm are delivering value-formoney. Since the pressure to justify such investment is high, the use of scientific evidence to aid decision-making has been encouraged. The systematic use of evidence to support decisions first emerged in the field of medicine, and has since been adopted in other fields, such as management and design. In relation to healthcare projects, several studies mentioned the use of evidence in supporting design decisions.1,2,3,4 These studies reported the findings based on different theoretical frameworks, and there are myriad subjects and methods that have been used to investigate the effects of the built environment on health outcomes. This knowledge domain is multidisciplinary in nature, and contributions have been made in different fields, ranging from medical to engineering research. Although there are certain implications of adopting evidencebased design (EBD) in practice, these have not been investigated extensively. In this respect this paper discusses several aspects related to the practice of EBD in healthcare projects. For that purpose an extensive literature review was conducted on the relationship between healthcare environments and health outcomes. In addition, workshops with designers, healthcare planners, and project managers, were carried out to support the arguments presented. Preliminary results show there are difficulties related to the collection and compilation of evidence, as well as its implementation throughout the project lifecycle. The idea of using evidence to inform decision-makers in design is, of course, not new in the context of healthcare buildings. Early in the 1960s the UK National Health Service (NHS) began developing Health Building Notes (HBNs) and Health Technical Memoranda (HTMs) with a basis on evidence. Since then those documents have been updated with current scientific findings and good practices. In addition there are more recently developed tools to support EBD, such as the NHS Environmental Assessment Tool (NEAT), Achieving Excellence Design Evaluation Toolkit (AEDET Evolution), and A Staff/Patient Environment Calibration Tool (ASPECT).

The evidence-based approach

Using scientific evidence to support decision-making is a simple and powerful concept. In medicine, for instance, this approach has been used to decide on the best treatment alternative for the patient. This involves identifying, for example, which treatment has the shortest healing time; which ones cause the least sideeffects and impact least on patients’ quality of life, and which ones are most affordable.5 The search for evidence in the evidencebased approach in general requires the use of systematic literature reviews. These follow pre-determined, rigorous steps that strengthen the searching process. Although systematic reviews are generally time-consuming, the results usually lead to identification of rigorous research studies and/or knowledge gaps. Additionally, following a systematic approach improves trackability, allowing the process to be replicated, therefore improving the reliability of the search.5,6 The opportunity to learn lessons from similar cases and apply such knowledge in real contexts has attracted the attention of many professionals. As a result, the evidence-based approach has been adopted in other areas, including education,7 economics,8 management,6 and design.9 As in evidence-based medicine, the aim of EBD is to achieve better-informed design decisions. EBD is defined as “the deliberate attempt to base building decisions on the best available research evidence with the goal of improving outcomes, and of continuing to monitor the success or failure for subsequent decision-making”.9 The principles of EBD follow the principles established in medicine. However, unlike evidence-based medicine, the full application of systematic reviews in design is limited. Research methods are simply limited in terms of gathering knowledge from such a complex and dynamic phenomenon. In addition, the lack of explicit cause and effect relationships, and the fragmentation and sparseness of the knowledge base, also affect the adoption of the evidencebased approach.10,11