Ana-Karinna Hidalgo, Ph.D.

Abstract

This paper is aimed at answering the following research questions: What are the most common research methods used in environmental design studies and practice? Are those methods aimed at providing evidence? What is it missing? Why is this important for environmental design?

In order to find out the methods used in environmental design and whether or not they provide evidence, an extensive literature review is being conducted. This study is divided into three phases of research: 1. A review of methods; quantitative vs. qualitative, 2. Analysis of research studies and outcomes, and 3. Experimental design.

This paper is focused on the analysis of this first phase that includes the review of research methods of the top seminal authors in urban planning, environmental design and the specific topic on mental health in the built environment. A comprehensive review of methods used in the research studies published in the EDRA conference proceedings from 1969 (EDRA 01) to 2018 (EDRA 49) has been conducted.

The findings from this first phase show that the field of environmental design has developed theories based on essays, grounded theory and professional practice, that later became seminal works. Environmental design borrows methods and theories form other disciplines, particularly from social sciences that have enriched our interdisciplinary field. The most common research methods used are of a qualitative approach. Quantitative methods, particularly experimental methods, are scant in the field as reduced is the number of empirical based research (Brown, 2018; Cuthbert, 2011; Marshall, 2012).

1. Introduction

The field of environmental design has been fed by research and studies of other related fields such as environmental psychology, biology, geography, economics, sociology, civil engineering and history. Certainly the field has also developed its own research and even contributes to others such as education and psychology. Designers, urban planners, architects and artists use this interdisciplinary knowledge in the creation of objects, environments, methods and systems at different scales.

Some studies even inform public policies, influence in shaping cities and in building hospitals and schools. Environmental design research, studies and development imply a great civic and social responsibility as they are shaping the public and private spaces that should be healthy and comfortable, environmentally friendly and with a baggage of culture, social inclusion and affordability.

However, the same interdisciplinary background and its broad application are at the same time its strength and its biggest weakness. As Blake (1980) points outs, the benefits of being better equipped brought by an interdisciplinary approach, may imply researchers working in projects outside their area of expertise. This broad range of environmental design topics also brings a world of possibilities to address a research study from different perspectives. One may think that the research done in environmental design has a rich variety of methods conducted to answer questions on the relationships between people and the environment at different scales, layers, levels and from different perspectives.

With this diverse background, this paper is aimed at answering the following research questions: What are the most common research methods used in environmental design studies and practice? Are those methods aimed at providing evidence? What is it missing? Why is this important for environmental design?

This paper addresses those questions by analyzing publications on environmental design as the big container of other design fields, publications in the fields of urban planning and urban design, and publications on a specific environmental topic. The work presented in this paper includes portions of the methodological analysis written on Chapter 4 of the doctoral dissertation Streets for Mental Health: An Interdisciplinary to Restorative Urban Design (Hidalgo, 2019).

2. Methodology

In order to find out the methods used in environmental design and whether or not they provide evidence, an extensive literature review is being conducted. This study is divided into three phases of research (Image 1): 1. A review of methods; quantitative vs. qualitative, 2. Analysis of research studies and outcomes, and 3. Experimental design.

The first phase includes the scan and overview of the Environmental Design Research Association Conference proceedings (from EDRA 01 Chapel Hill to EDRA49 Oklahoma) and of the top 100 seminal works in urban design and planning according to the American Planning Association (APA, 2009). During this phase, a more detailed literature review is conducted for a specific topic (relationship environment-mental health-restoration) in order to determine whether or not each study identifies correlation or cause-and-effect relationship among variables.

A second phase is designed to provide a detailed analysis on the research methods, tools and outcomes of the research. A more extensive matrix of methods used in referred papers published in the proceedings of EDRA Conferences is being populated. This phase will help analyzing the implications of such studies on public policies or academic innovations as well the academic networks created.

The third phase is aimed at conducting experimental design in order to test selected theories and findings from the literature review. The evidence-based research on this phase can inform public policies in the design and development of methods, tools, objects and spaces.

This paper addresses the analysis and results of this first phase that includes the review of research methods in environmental design, of the top seminal authors in urban planning, and the specific topic on mental health in the built environment.

Image 1. Methodological phases.

3. Methods review

3.1 Environmental design research analysis

At the first EDRA Conference (EDRA1 Chapel Hill), a diversity of studies was presented from a broad range of topics. Studies focusing on the technical aspects of the environment, perception and responses to the environment, human behavior, participatory approaches and design pedagogy with a variety of methods within were presented. With some variations and the inclusion of topics related to new technologies, EDRA conferences have been covering thoroughly the various aspects of environmental design.

Nonetheless, the methodological aspects of research methods have not developed at a similar speed than the research topics, nor they produce enough evidence or have challenging previous theories, policies and concepts for the strengthen of the field.

The lack of quantitative methods across the papers published may have different reasons. Minimum use and teaching of them at undergraduate or graduate levels, unfamiliarity or inexperience or the “culture” of specific topics or fields, may be some of the arguments against using more quantitative methods in environmental design. This limited amount of quantitative methods, particularly experimental methods, leads to the lack of cause-and-effect relationships between environment and users.

We still do not know why many places cause certain behaviors, or illnesses, or attitudes, nor if the reason of such design is because users decided based on their own personality or if it is the place the one that frames such personality.

Interestingly, the need for a more rigorous research in the field has been constantly claim. A reflection paper in EDRA1 suggests increasing such rigorosity through environmental quality including, for example, the use of scientific studies plus the analysis of day-to-day documents such as poems, television, religious texts, jokes and songs (Rapoport, 1969). Rapoport also suggests that it is premature to change to experimental research in that time period (1960’s). Is it still too premature for the field to start establishing cause-and-effect relationships through experimental design? Environmental design, as well as other academic fields, does not need to change to a different research model, it should, however, present rigorous, evidence-based research studies.

For the purpose of the EDRA Conference Proceedings analysis, the publications were divided by 5-year time periods (Table 1). Two main reasons guide this decision: 1. to avoid a direct analysis or critic on each conference, school or city and, 2. to establish a trend in a larger period of time. Only full papers published on EDRA proceedings at the organization website were considered for the analysis.

Table 1. 5-year time periods – EDRA Conference Proceedings

The criterion to determine the method is based on what the author(s) declared. The research methods were classified as follows: qualitative methods, quantitative methods (with emphasis on finding the amount of experiments), mixed methods, literature review, methodology focused and others. A classification of ‘no method mentioned’ was also considered.

3.1.1 Findings from EDRA Proceedings

Along the different periods of time, qualitative methods have lead environmental design studies. The first decade (EDRA1, 1969 to EDRA10, 1979) presents a more balanced distribution of research methods (Image 2). From the 80’s, the trend changes abruptly; interestingly most of seminal works on which the design of cities and towns is based were born during this decade.

Image 2. Research methods per 5-year time period.

A closer analysis to quantitative methods shows that few studies are aimed at finding cause-and-effect relationships. The percentage of experimental design methods is constantly below the 10% in relation to other quantitative and qualitative methods (Image 3). Moreover, some studies although explicitly mentioning that they conducted an experiment, they failed to implement randomization. Problems of order effects, sample size and power are also found. All these problems prevent to establish causality.

Image 3. Quantitative methods: surveys and others vs. experiments

From all the publications analyzed, the influencing field, and possible the topic, determines the research method. For instance, most of researchers that are looking at behavioral relationships are likely to select quantitative methods, from them, few select experimental design. In some cases, some authors decide on mixed methods, being the qualitative method the second to be conducted, in order to confirm their findings or justify them. Once again, this second step of requiring a qualitative confirmation when the research does not need to (and that is not common in other disciplines) weakens the value of quantitative methods, in particular experimental design. Therefore, the evidence presented by quantitative studies is not equally considered as the findings or conclusions (evidence-based or not) coming from qualitative methods.

The next section will cover one subfield of environmental design that is related to the design of cities and the public space. It covers the top seminal works in urban planning and urban design in a more detailed analysis.

3.2 Determining the main research methods in urban planning

The design of cities and towns, although inherited from the organization of the first communities, is being influenced by ideas and theories that influenced in the decision-making process. Most of these ideas have been taught at planning schools with the aid of seminal books. Using the list of 100 seminal books published by the American Planning Association, we selected the top 5 seminal authors using Google Scholar citations (as of April, 2019) as a reference number and selecting those books whose content is specifically of urban planning and urban design.

The following works are considered in this analysis: The Organization Man (1956, cited by 6,611) and The Social Life of Small Urban Spaces (1980, cited by 3,145) by William Whyte, The Image of the City (1960, cited by 18,048) and A theory of Good City Form (1981, cited by 3,344) by Kevin Lynch, The Death and Life of Great American Cities (1961, cited by 23,130) by Jane Jacobs, Life Between Buildings (1971, cited by 3,896) by Jan Gehl, and The City in History (1961, cited by 6289) by Lewis Mumford.

William Whyte’s main works influenced business and urban planning. With a background in anthropologist and journalism, his book The Organization Man (1956) focused on the corporate culture and management. But it is The Social Life of Small Urban Spaces (1980) the book that influenced the urban planning field.

Whyte’s planning work is based on observational studies on how people behave on urban settings. He studied people’s social activities and documented them in photographs. Cameras were placed and experimented at different places and with different angles obtaining time-lapse photography. Ethics for filming and photographing people are not considered.

The evaluation of his recorded photos and videos consisted on the analysis of plazas, streets, the use of the sitting space and the influence of natural features such as sun, wind, trees and water where observed. Clearly his observational studies concentrate in business districts and activities happening there. Once the team gathered the images, they make a simple map to trace people’s activities. Then they started asking questions and hypothesizing about people’s behavior in the urban setting (Whyte, 1980). His work cannot be assessed in order to understand what makes a place more livable because his research do not establish causality and he never presents the statistics of it (Abdulkarim & Nasar, 2014).

A controversial chapter of his work The “Undesirables” sadly presents people that are not desired by businessmen and retailers (Whyte, 1980:60). Instead of stating a critic to what they called a problem, and finding a solution for inclusion, Whyte suggests that by beautifying the place, the undesirables will go somewhere else. Further studies will say the opposite, ugly places will take them away (Goodyear, 2012). Both positions go against inclusion and equality in the public space.

Kevin Lynch’s work on environmental legibility contributes to the fields of urban design and environmental psychology. The Image of the City constitutes a classic text for the study of urban ‘legibility’ (Lynch, 1960). The way in which humans think about their environment and how people create their mental images (Kopec, 2006; Gifford, 2014) determine the basic elements of legibility as follows: paths, edges, districts, nodes and landmarks. Even if these elements were not the result of a rigorous study and were “suggested by Lynch speculatively, without much formal research” (Gifford, 2014:34), some experimental methods have confirmed their validity in the field of environmental psychology (i.e. the confirmation of Lynch’s categories by Aragones & Arredondo, 1985).

A different approach was adopted in A theory of good city form (Lynch, 1982) that includes an urban historical analysis, concepts and theories related to urban design and city planning, conceptualization of theory, and specific proposals and concepts of good city form. In this theoretical work, Lynch proposes five performance dimensions for a city to provide residents with biological, social, psychological, and cultural requirements: vitality, sense, fit, access and control.

Among the authors selected, Lynch’s work adopts a more scientific approach. Lynch’s evidence results from both primary data (mental mapping for the development of legible elements of the city) and secondary sources to feed the empirical knowledge that was being developed. Lynch offers two types of theory. The first one is a deductive theory in his work A Theory of Good City Form where he considers the history, theory and big concepts related to the city, policies and urban theories in order to propose dimensions and elements of cities, and to suggest applications and specific topics of the urban form. The second theory of inductive nature introduced in The Image of the City where he proposes the five elements of a city that transcend the boundaries of urban design.

Jacobs’ book The Death and Life of Great American Cities (1961) has been one of the most influential books for city planning. She criticizes the city planning of the 50’s and the way in which architecture and planning students were learning the field. She introduces new principles for planning and rebuilding attempting a shift in this field towards people-centred neighbourhoods.

Jacobs’s proposal is based on her own observations of life on streets, her experience living on Greenwich Village, a well-known vibrant downtown neighbourhood in New York City, and her activism against new developments and urban renewal plans of Robert Moses. For Jacobs, the way to learn principles and practices of planning that can promote social and economic vitality is the understanding of cities in the context of the real life.

The evidence that supports and propagates her ideas are also based on personal observation that her supporters employ even today, almost 60 years after her book was written. Critics to her ideas celebrate the modern and orthodox city planning that encourages the development of highways and expressways, standardized commercial centres and other modern features over liveable neighbourhoods or, as Jacobs states, the real city life.

From a methodological perspective, Jacobs’ methods consists of an accumulation of her experiences of cities and analyses, which constitute a qualitative approach producing information from primary sources that result from personal observation. It is worth mentioning that Jacobs does not explicitly indicate how places were studied, and how information was collected, selected and analyzed. Her claims about the district and block characteristics have not been tested; several authors have constantly critic her work as ‘unscientific’ and ‘anecdotal’ and lacking of support (Marshall, 2012). Jacobs’ contribution resulted from a personal-observation approach; her concepts go from the particular (a neighbourhood analysis) to a broader generalization (concepts such as ‘street ballet’ and ‘eyes on streets’ to be used broadly in cities).

Gehl has carried out several field studies since the 1960’s. Life between buildings (Gehl, 2011–first published in 1971) is considered an influential book because the synthesis of his studies about public life and human behaviour in cities resulted in categories and patterns of outdoor activities and types of public places. His categorization of activities and the consideration of the elements that a public space should include are the result of studies conducted by Jan Gehl and Gehl Architects in cities of Italy, Denmark, Sweden, Latvia, USA, Australia, among others (Gehl & Svarre, 2013). His book Cities for people (2010, cited by 2122, not included in APA list) is a theoretical synthesis of his studies on cities and people with an emphasis on liveable, healthy, safe and sustainable cities that considers public realm, human scale and the eye level concept. It proposes principles and criteria as a design toolbox for city planning. A strong emphasis is put on the concept that ‘life’ on streets and public places is the first that needs to be considered and should be visible in cities; the concepts of ‘space’ and ‘buildings’, as city elements, come after.

The research methods used include keeping a diary, tracing, photographing, counting, behavioural mapping and observation. His concepts and theories are supported by evidence from primary sources (i.e. observation). Gehl's studies generate concepts and guidelines about people's life in cities, mainly pedestrians' behaviour in public spaces.

Mumford, a historian and writer, is the author of The City in History (1961), an influential and comprehensive historical book on cities. The contents of the book cover the origins of the city, its transformation, expectations and visions of the ideal city. Although the book has analysis of various cities and cultures, he regrets not including more regions in his historical studies.

The methods he uses include literature review, personal experience, first hand data and observation. The analysis he makes on cities highlights the natural landscapes, how cultures relates to them and evolved, and how current cities have not develop further in the knowledge of the land but in the development of industries and buildings. His analysis condemns the megalopolis due to its negative effects on the quality of life. Moreover, he praises the suburban healthy, organized and decentralized suburban development in the form of an old village component or a neighborhood organization (Mumford, 1961).

Interestingly, these seminal works do not necessarily coincide on the findings. The work of Gehl, Jacobs and Whyte do agree on the importance of the social life and suggests elements to improve it. However, none of these studies establish causality; therefore, there are not enough criteria to decide about what components of the built environment contributes on positive behaviors and social health in the urban environment.

Lynch’s work differs from the above-cited authors. His studies on the urban form in connection to human values and mental images provide elements and requirements towards the understanding of cities. He provides theoretical constructs build upon a scientific approach (A Theory of Good City Form, 1982).

Mumford has a different path in reading and studying the city; his findings go in a different direction. However, Mumford does not agree with the first group of authors in the proposal of urban life. For instance, several articles relate to the constant disagreements between Mumford and Jacobs. None of them are quantitative research; none of them follows a rigorous and scientific path, none of them have tested their proposals and none of those proposals have being fully developed.

3.3 Methods on a specific topic: relationship environment-mental health-restoration

The initial motivation to carry out this research on methods was a study on public environments that improves people’s mental health (doctoral dissertation - Hidalgo, 2019). In the search for findings and methods on the topic on both environmental psychology and urban planning, the lack of evidence-based research on the second one calls my attention. Parallel to the doctoral dissertation, the study of research methods for environmental design has begun.

The study on environments for mental health includes a comprehensive matrix with research studies published in academic journals and seminal books. This analysis includes a literature review of 35 published studies that are widely cited during the last three decades. The matrix includes research studies on validation of tools for experiments, urban methods, surveys and questionnaires, and field and laboratory experiments aimed to answer questions about the relationship among built and natural environment, mental health and psychological restoration. Eight out of those thirty-five studies conducted lab or field experiments (Table 2). Although all of them provide with evidence, only half of the experiments were able to establish a causal relationship.

Table 2. Lab and field experiments - environment-mental health-restoration

This analysis shoes that on this specific topic of mental health and the urban environment, only few research studies belong to urban design and planning. However, none of them provide causality. In general, few works in urban design research are on the scientific track (Mehta, 2013). Scientific evidence on how people behave, experience or perceive the environment has been usually provided by other environmental disciplines. Environmental psychology, for instance, offers evidence on the determinants of people’s well-being in the environment effects.

However, evidence on environmental related-topics has not necessarily been used by urban design. Moreover, urban design is not generating enough evidence on this topic, where most of the theory is based on a subjective approach generated from intuition and experience (Cuthbert, 2011).

As show in section 3, qualitative methods are widely used in environmental design. Most of the research studies on the relationship between the built environmental and health is correlational (Brown, 2018). The challenges that imply conducting experimental studies to establish causality result on a limited number of quantitative research in urban planning. Therefore, the main methodological approaches used in urban planning are of qualitative nature such as observation and the use of implemented projects and policies as precedents for the development of new ones.

4. Discussion

The capacity of a field to evolve depends greatly on its capacity to clarify, test and being opposed to and challenge current theories. As Cuthbert (2011) states, the development of new knowledge does not mean a lack of respect of current theories and concepts, nor it means a complete deconstruction of what exists; it is just a clarification on the way the world is understood.

This ‘loyalty’ to theory or authors in place restrains the development of the field. Most of the academic and professional discussions about the appropriateness of the method have been rested on the field/s behind it and not on how the method is addressing and helping in answering the research question. The main discussion should not be politics, ideologies, affiliations or loyalties related to other fields or methods, not even philosophical assumptions or tradition of the field; the discussion should be how a specific method answers the research question.

By liberating research methods in the field, new research studies will show the interdisciplinary nature of the field not only by the diverse topics but also by the different methods used. The amount of qualitative methods in comparison to quantitative and mixed methods and literature review, shown in Image 2, is clearly higher. Why this interdisciplinary field responsible for the environment were everyone lives and thrives do not establish more causal relationships?

There is not right or wrong method. It is important, however, to choose the correct method to answers the research question formulated. The appropriateness of the use of quantitative and qualitative methods depends on the type of problem or research question under study. In this sense, each method can present strengths or weaknesses depending on how they are going to be used (Table 3).

Table 3. Strengths and weaknesses of research methods

Source: Author (based on Hidalgo, 2019; Creswell, 2009; Gehl & Svarre, 2013; Charnes et al., 2012)

Along these years, the concern of pushing urban design to a more scientific approach is recurrent, in particular when designing the public space. Marshall (2012) warns that if urban design theorists do not consider science, other fields will do and develop the environmental knowledge from then. Bechtel (1993) suggests that EDRA uses social science research to empower the environmental design field and to change the way students are learning. The need of a more rigorous research and scientific approaches has been there always and different authors have claimed it already, when do we decided not to listen to them?

Current students of environmental design and related fields would want to excel at quantitative and qualitative research methods. Future academics and professionals should feel confident on choosing the method not because everyone does it in the field or at any specific school, not because the seminal works are based on them, but because it is the correct method for the research that is being conducted. We have a tremendous responsibility on teaching them all. Are we really prepared to teach research skills to our students? Where are we heading in the next 50 years? Are we going to repeat the same academic discourses?

Acknowledgement

I wish to thank Oscar Zapata, Ph.D., Postdoctoral fellow in the School of Community and Regional Planning at the University of British Columbia for his valuable help and advice along this research project.

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