Not Good Enough? Exploring Relationships Between Novice Designers’ Trait Empathy, Their Beliefs, Attitudes, and Intentions Toward Sustainability, and the Self-Evaluated Sustainability of Their Solutions

Engineers can play a critical role in addressing global environmental problems by adopting sustainable engineering practices [1,2]. Therefore, engineering educators must give sufficient emphasis on sustainability to ensure that engineers are motivated and have the skills needed to work toward these issues [3,4]. For example, Blewitt [5] argues for educators in higher education to emphasize the development of a sustainability-focused mindset among individuals by incorporating social and environmentally conscious learning approaches.

In the context of engineering design and product development, Johansson [6] presents a review of the various factors that contribute to the successful incorporation of eco-design into product design and development. The author identifies 20 factors which are then categorized into six components: (1) management, (2) customer relationships, (3) supplier relationships, (4) development process and methods, (5) competencies, and (6) motivation. Of these six components, those of “competencies” and “motivation” are particularly important in the context of engineering design education. For example, Johansson [6] suggests that designers must adopt an environment-focused mindset and actively integrate eco-design techniques in the design process. Several researchers (e.g., see work by [7–9]) have further argued for the need for interpersonal competencies—i.e., one’s ability to engage with others and the community—among individuals to encourage the adoption of a sustainable mindset. The potential role of individual differences and interpersonal competencies has also been more broadly, linked to pro-environmental behaviors in individuals [10].

Of the various individual differences studied in engineering design and education, designers’ trait empathy—i.e., the reactions of one individual to the observed experiences of another [11]—has received recent attention [12]. Empathy has been attributed to effective team communication [13] and the understanding of different cultural expectations [14]. In engineering design, researchers argue that empathy plays an important role in the early conceptual stages of the design process (e.g., needs identification and concept generation). For example, Genco et al. [15] and Johnson et al. [16] observe that empathic design experiences (e.g., simulating visually impaired scenarios) positively impacted designers’ generation of creative ideas. Additionally, recent studies have also revealed the relationship between different components of empathy and designers’ identification of user needs [17] and problem framing in design tasks [18].

While prior research has explored the role of empathy in engineering design education, a majority of this research has focused on student designers’ ability to relate to the needs of the primary users involved in a particular design problem. Little research has explored the role of empathy in encouraging actions directed to benefit others indirectly, especially in the context of sustainability. This direction of work is important since engineers must empathize with those who experience both, the direct and indirect consequences of their design decisions. The need to explore this relationship is particularly underscored in the context of sustainability, as decisions related to sustainability might not always affect the primary user of the solution [9]. Moreover, these decisions might affect the designers even less, thereby necessitating the need to have diverse perspectives [9]. Designers’ ability to relate to the direct and indirect consequences of their decisions could influence their tendency to act upon these decisions and adopt sustainable design practices. Such an investigation is also emphasized in light of prior work suggesting that broader social and environmental contexts play an important role in the way students experience human-centered design [19]. Therefore, when engaging in sustainable design, designers must consider both, the needs of the user along with external aspects of the design context such as environmental sustainability. Moreover, designers must mindfully balance these different and potentially competing requirements [20] and make effective tradeoffs when making design decisions [21].

In light of this prior work, designers’ internal and interpersonal traits, specifically, their trait empathy and their beliefs, attitudes, and intentions toward sustainability, could influence the extent to which they actively incorporate environmental sustainability in their design process. However, little research has explored this relationship and our aim in this paper is to explore this research gap through an experimental study in the form of a workshop on sustainable design. Specifically, we studied changes in student designers’ trait empathy and their beliefs, attitudes, and intentions toward sustainability from before to after participating in the workshop. We also investigated the relationship between these individual differences and participants’ self-evaluated sustainability of their solutions generated in the design-based workshop. Through the outcomes of this study, we aim to provide a first step toward the study of the influence of designers’ internal and interpersonal traits on their active adoption of sustainability in engineering design.

Next, in Sec. 2, we discuss prior research that informed this study followed by the research questions and our corresponding hypotheses presented in Sec. 3. Our experimental methods are discussed in detail in Sec. 4; the analysis of the data collected, and corresponding results are presented in Sec. 5, and the implications of these results on design education are discussed in Sec. 6. Finally, we discuss the limitations of our work and present directions for future research in Sec. 7.

Our aim in this research is to investigate the relationship between designers’ internal and interpersonal traits—in particular, their trait empathy and their beliefs, attitudes, and intentions toward sustainability—and the self-evaluated sustainability of their solutions in a design task. Before doing so, prior research on sustainability and empathy in engineering design education is reviewed, as discussed next.

Given the emerging need for incorporating sustainability into engineering and design, several researchers have proposed educational tools and methods for integrating sustainability in engineering education (e.g., see work by Refs. [22–27]). For example, Ramirez-Mendoza et al. [28] discuss the incorporation of the United Nations Sustainable Development Goals (UN SDGs) through both, curricular programs at the graduate and undergraduate levels, and extra-curricular activities. Based on their experiences, they emphasize that academic programs must give equal importance to sustainability as other learning objectives to have a long-lasting impact [28].

Fitzpatrick [29] further echoes the need to emphasize sustainability in engineering education. The author extends this argument to say that in addition to the technical and engineering aspects of sustainable development, engineering educators must also emphasize the social and economic aspects of sustainability. The author suggests that this emphasis on the social and economic aspects of sustainability would result in engineers making decisions that supplement technical advances in the area of sustainable development. Toward meeting this need for the integration of the social lens of sustainability, Valderrama Pineda and Niero [30] present a graduate-level program on sustainable design engineering introduced at Aalborg University. In the program, students are given opportunities to interact with real-world situations and stakeholders to develop practical and theoretical skills, an approach also suggested by others [20]. A similar effort is presented by Kuzmina et al. [31] and Kuzmina and Bhamra [32], who argue for the use of participatory service design as an effective method for sustainable design education. These efforts suggest that the use of human-centered design educational methods could be more effective in sustainable design education. This idea is also reinforced by researchers [7–9] who argue for the need for individuals to develop interpersonal competencies such as a capacity for empathy, compassion, and self-motivation, to successfully adopt a sustainable mindset.

Researchers have extended this idea of leveraging empathy-driven sustainability in the context of engineering design education. For example, Lagun Mesquita and Missimer [33] present a workshop-style intervention to introduce engineering designers to sustainability from a social lens. In their intervention, students are asked to consider the social and environmental impacts of a product. In the first phase of the intervention, students were given no inputs, whereas, in the second phase, they were given specific inputs about the different stages of the life cycle of the product (e.g., the manufacturing process used for the product). One of their key findings was that a majority of the students perceived both phases of the intervention to be difficult. This finding suggests that despite providing external cues, designers possibly find it difficult to incorporate aspects of sustainability in the product design process. A similar observation is made by Björnberg et al. [34] in their series of interviews with educators. They observe that educators also find it difficult to both, understand, and convey concepts of sustainability from a social lens—i.e., how sustainability could influence other humans. They suggest the lack of evidence-based techniques as a possible cause for the perceived difficulty. Similarly, Ritter et al. [24] present a project-based module emphasizing the social, environmental, and economical sides of sustainability.

Kattwinkel et al. [35] present a study investigating the incorporation of eco-design and sustainable design in product development. The authors highlight the lack of emphasis on eco-design in product development and suggest the need for higher education to emphasize these concepts. They, in Ref. [36], further compare the various competencies required in product development, sustainable development, and eco-design, to identify similarities between the three categories. Of the various competencies identified by the authors, they observe that the ability to engage and connect with diverse groups of people demonstrated the greatest overlap and emphasis. This finding further reinforces the importance of the social dimension of sustainable design.

Taken together, we see that several researchers have proposed educational tools and techniques for incorporating sustainability into engineering design education. While some studies have explored the outcomes of these educational interventions on student designers’ knowledge of sustainable engineering practices, little research has explored the influence of these interventions on their internal and interpersonal traits. Such an investigation is important because prior research suggests that individuals’ internal traits play an important role in determining their tendency to actively engage in pro-social and pro-environmental behavior. For example, researchers [37,38] have employed the theory of planned behavior [39] to predict one’s tendency toward pro-environmental behavior. According to this theory, one’s beliefs about the need for certain action combined with their attitude to take said action in the present and their intentions for future action are strong predictors of behavior. This theory has been employed to explain pro-environmental behavior in contexts such as recycling [40], composting [41], and water conservation [42]. Similarly, Sawitri et al. [43] argue that one’s tendency to engage in pro-environmental behavior can also be predicted using the social cognitive theory; they suggest that intrinsic factors such as self-efficacy perform certain actions and one’s interests guide one’s tendency toward pro-environmental behavior.

In light of these studies, we see that sustainable design education must not only positively influence student designers’ knowledge of environmental sustainability and the technical concepts involved, but also positively influence internal factors such as beliefs, attitudes, and intentions toward environmental sustainability. Such efforts could leverage designers’ internal traits to encourage an active engagement in sustainable design practices. However, little research has explored the relationship between student designers’ internal traits and their approach to sustainable design, and our aim in this research is to explore this research gap from a design educational lens. Next, we review prior research on empathy in engineering design education as discussed next.

Research on empathy in engineering design education has seen a surge over the past decade [12]. This interest in integrating empathy in engineering design could be attributed to the importance of empathy in helping designers better understand the needs of users [44,45] and the design problem itself [46]. Moreover, in a qualitative study, Fila and Hess [13] find empathy to be related to effective teamwork, problem contextualization, and individual design inspiration.

Researchers in engineering design argue for the potential role of both the cognitive and affective components of designers’ empathy to better understand the end-user’s needs [47]. Specifically, an individual’s empathy can be categorized into four distinct components: (1) perspective-taking, (2) fantasy, (3) empathic concern, and (4) personal distress. Perspective-taking measures one’s ability “to adopt the psychological point of view of others” (fantasy measures one’s “tendency to transpose themselves imaginatively into the feelings and actions of fictitious characters in books, movies, and plays” (p. 2, [48]), and empathic concern measures one’s “other-oriented feelings of sympathy and concern for unfortunate others” (p. 2, [48]), and personal distress measures one’s “self-oriented feelings of personal anxiety and unease in tense interpersonal settings” (p. 2, [48]). Prior research has also shown that the different components of empathy relate to one’s ability to effectively understand users’ needs. For example, Alsager Alzayed et al. observe that designers’ empathic concern relates to their identification of user needs and the assessment and organization of these needs in the design process. Similarly, Prabhu, Alsager Alzayed et al. observe that designers’ perspective-taking positively correlated with their identification of user-focused requirements in a sustainability-focused human-centered design task.

In addition to supporting problem requirement identification, researchers have also found empathic design experiences to be an effective method to support creative ideation in the conceptual design stages [16]. Specifically, Raviselvam et al. [49] demonstrate the use of virtual reality to simulate scenarios involving visually impaired users. They argue that these simulations enhance students’ empathic self-efficacy and creative ideation. A similar observation is made by Alzayed Alsager et al. [50] and Alzayed Alsager et al. (2020) [51]; they find that three of the four subscales of students’ trait empathy (i.e., empathic concern, personal distress, and perspective-taking) relate to creative ideation. Furthermore, they observe that students’ empathic concern positively correlated with the number of ideas generated by students, whereas personal distress and perspective-taking negatively correlated with the number of ideas. In a team-based design study conducted by the same group, high team empathy was found to positively relate to the teams’ generation and selection of unique ideas [51]. In addition to the impact of empathy on design outcomes, Surma-Aho et al. [52] observe that trait empathy is positively related to students’ confidence in design-related experiments. These findings highlight the importance of empathy during the idea generation and selection stages of the design process and the role of empathy in influencing designers’ confidence in their design decisions, which can be an indicator of future success.

Furthermore, prior work suggests that individuals’ empathy manifests along two paths: (1) imagining how others feel in a particular situation and (2) imagining how the individual themselves would feel in a situation [53–55]. Of the two paths, the latter has particularly been shown to trigger an individual’s personal distress, i.e., one’s tendency to act upon their feelings of empathy [53–55]. Therefore, designers’ tendency to act on issues related to sustainability could be influenced by their perception of and distance from these issues. For example, if designers perceive that they could one day face the ill effects of their unsustainable decisions, they might have a more active response to correct these decisions. On the other hand, if students perceive that these ill effects only affect others, they might be less likely to correct their decisions [56,57]. However, little research has investigated the influence of designers’ empathy on their adoption of sustainable design practices, and our aim in this research is to explore this research gap. Toward this aim, we seek answers to the research questions (RQs) discussed next.

Our aim in this research is to investigate the influence of designers’ internal and interpersonal traits—in particular, their trait empathy and their beliefs, attitudes, and intentions toward sustainability—on the self-evaluated sustainability of their solutions. Toward this aim, we seek answers to the following RQs:

• RQ1: How do student designers’ trait empathy and their beliefs, attitudes, and intentions toward sustainability change from before to after participating in the sustainable design workshop? Moreover, is this change influenced by the point at which the sustainable design lecture is introduced (i.e., before and after the design activity)?

• RQ2: How does the point at which the sustainable design lecture is introduced (i.e., before and after the design activity) influence student designers’ self-evaluated sustainability of their solutions?

• RQ3: How do student designers’ trait empathy and their beliefs, attitudes, and intentions toward sustainability collected post-intervention relate to the self-evaluated sustainability of their solutions?

First, we hypothesize that the sustainable design workshop will have a positive influence on participants’ beliefs, attitudes, and intentions toward sustainability but not necessarily on their trait empathy. This hypothesis is based on prior work highlighting the difficulty of conveying the social aspects of sustainability in engineering education [34]. Second, we hypothesize that participants who received the sustainable design lecture first would report higher self-evaluated sustainability of their solutions. This hypothesis is based on previous research suggesting the utility of short-form workshops on sustainable design toward encouraging the integration of sustainability in engineering design [58]. Finally, we hypothesize that participants’ trait empathy would positively correlate with the self-evaluated sustainability of their solutions. This hypothesis is based on prior work, suggesting that novice designers demonstrate more positive concept evaluations when provided with empathy-related instruction [59]. This hypothesis is also based on prior work suggesting the importance of interpersonal competencies (e.g., compassion and empathy) toward sustainable behavior [36].

To answer these research questions, we conducted an experiment with undergraduate students. The experiment was reviewed and approved by the Institutional Review Board before it was conducted. The details of the experiment, including the participants, procedure, and metrics, are discussed in this section.

The participants were recruited from two sections of a first-year introductory course on engineering design at a large public university in the northeastern United States. Both sections were taught by one of the authors leading to a convenience sampling strategy [60]. Although the experiment was conducted as a module in a semester-long course, participants were informed that the use of their data was completely voluntary and that their decision to participate in the experiment will not be revealed to the instructor until after the semester was completed and the grades were entered. Of the 40 consenting participants, 38 completed both, the pre- and post-intervention surveys, of which 34 participants were in their first year of study, two in their second year of study, and one in their third and fourth year, each. Additionally, 25 participants self-identified as male, and 13 self-identified as female when asked for gender. Finally, since participants were in the first year of study, they had not yet declared a major; however, all participants were intended, engineering students. It should be noted that in this research, we investigated the impact of empathic tendencies on participants’ design behavior; however, we did not investigate the effects of other individual differences (e.g., gender) [48]. Therefore, future research is warranted to examine the impact of such individual differences on the findings of this work. It should be noted that one section (treatment, N = 22) was given a lecture on the sustainable design before the design activity, whereas the second section (control, N = 18) was given the lecture after the design activity (Sec. 4.2.2). Since the experiment was conducted as a module in the course, we chose to split the participants based on the sections in the course to minimize any disruptions, leading to an unbalanced distribution of participants between the treatment and control conditions.

At the beginning of the experiment, participants were introduced to the overall objectives of the study and consent was obtained through email. It should be noted that the experiment was conducted entirely online over Zoom given the challenges imposed by the COVID-19 pandemic. Since the experiment was conducted over Zoom, we used the participants’ submissions of the various components of the experiments to establish their engagement, including listening to the lecture. Participants with data missing from any one stage of the experiment were completely removed from the analysis. However, this assumption is a potential limitation of this study and is an artifact of the online nature of the experiment. Additionally, since the experiment was introduced as a module in a semester-long course, the primary instructor—also the third author (EMS)—executed most of the experiment. The experiment was conducted over two days with each day comprising a ∼1.5-hour session and one day between the two sessions. We present an overview of the experiment in Fig. 1. Additionally, the design activity comprised four sub-stages (requirements identification, concept generation, concept evaluation, and concept selection); however, since the data from these stages are not used in this paper, only the relevant stages are discussed in detail.

For the first part of the experiment, participants were asked to complete a pre-intervention survey comprising (1) demographic questions (e.g., year of study), (2) the 28-item Interpersonal Reactivity Index (IRI) scale to capture their trait empathy, and (3) a 25-item survey to capture their beliefs, attitudes, and intentions toward sustainability. Participants completed the survey in class time and were provided with the link to the survey before the class period started.

Specifically, participants’ trait empathy was measured using the IRI [48], a 28-item scale comprising four subscales: (1) perspective-taking, (2) fantasy, (3) empathic concern, and (4) personal distress. Participants were asked to respond to the 28 items on a 5-point Likert scale with 1 = “Strongly Disagree” and 5 = “Strongly Agree,” The IRI was chosen for this study as it captures both, the cognitive and affective components of empathy [61], and these two components help students to understand users’ needs [47]. Moreover, the IRI has been used in prior studies in engineering design research [52,62]. The reliability of the participants’ IRI responses was established through an observed Cronbach's α [63] > 0.7 within each subscale.

Additionally, participants’ beliefs, attitudes, and intentions toward sustainability were collected using the 25-item survey developed [64]. This scale comprises six items (e.g., “I feel morally obliged to do something about environmental problems”) that capture the participants’ beliefs in the need for sustainable action. Additionally, 13 items (e.g., “I make an effort to use energy and resources efficiently”) capture their present attitudes toward engaging in environmentally sustainable actions. Finally, six items in the scale (e.g., “I intend to change/continue to change my lifestyle for better sustainability”) capture participants’ intentions to engage in sustainable action in the future. Participants were asked to respond to the 25 items on a 5-point Likert scale ranging from strongly disagree to strongly agree. This scale was used as it captures both, individuals’ beliefs in the issues related to sustainability and their tendency to act sustainability in the present (i.e., attitudes) and the future (i.e., intentions). The reliability of participants’ responses was established through an observed Cronbach's α > 0.7 within each component.

While these surveys were chosen based on prior work, it is important to note that the use of a 53-item survey could be prone to survey fatigue [65], resulting in potential threats to the validity of survey responses. Consequently, future iterations of this study could include attention check items [66] to ensure participants’ attention when responding to the survey. Moreover, both these instruments assess the corresponding constructs from a general behavioral lens as opposed to one’s behavior in the context of engineering design. This decision was made given the exploratory, theory-building nature of this study [67] and due to the lack of domain-specific measures for the assessment of the constructs [68]. Prior research suggests that context could influence the relationship between individual differences and one’s behavior [69], and therefore, future work must explore the development and validation of domain-specific assessments of the constructs used in our study.

Several researchers have proposed interventions for introducing designers to sustainability including short- and long-duration interventions. Some examples of short-duration interventions include the priming technique tested by Liao and MacDonald [70] and She and MacDonald [71] and the guided questions tested by Ruiz-Pastor et al. [72] in which designers are provided with short prompts to trigger an emphasis on sustainability. In contrast, researchers have also proposed longer interventions such as workshops [73] and graduate-level programs [30]. Informed by these prior studies on sustainable design interventions of varying durations and given the theory-building nature of our study, we used a short-duration lecture on sustainable design. Specifically, participants from one group (Group A, N = 22) were given a lecture on sustainable design techniques to introduce them to the topic. In the 10-min lecture, participants were introduced to the concepts of lifecycle assessment, “cradle to grave” solutions, and the ten sustainable design principles proposed in Ref. [74]: (1) disposal, (2) salvage, (3) recycle, (4) remanufacture for reuse, (5) reuse as is, (6) longevity, (7) sharing for maximal use, (8) achieving heirloom status, (9) finding wholesome alternatives, and (10) active repair of misuse. These ten principles were chosen given their alignment with the six design for environment strategies identified by Telenko et al. [75], based on their review of the literature. At the end of the introductory sustainability lecture, participants were introduced to the 17 UN SDGs. After an overview of the SDGs, the instructor highlighted SDG #6: Clean water and sanitation, and this was used to transition from the sustainability lecture to the design task. On the other hand, participants from the second group (Group B, N = 18) received the same lecture after completing the design activity; these participants directly started with the design activity, discussed next.

Participants were asked to complete a design activity comprising four stages as discussed next. Participants were asked to complete all stages of the design activity individually.

1. Problem Introduction (5 min): First, the participants were introduced to the problem statement and were given the following information:

   In Sub-Saharan Africa, nearly 46 people die per 100,000 people due to diseases caused by the lack of safe water, sanitation, and hygiene (WASH) services. This is nearly four times the global average of 12 deaths per 100,000 people due to poor access to WASH services. You are tasked with designing a solution to help improve access to clean water and sanitation for Eli and others in his village.

   Participants were also given the following persona to provide them with more information about the problem:

   Eli is a 40-year-old man who lives in the Sub-Saharan African region. He lives with his wife and two teenage children. He is a farmer by profession—a low-income profession—and has received some middle-school level education. Eli lives in a small remote village with some access to electricity but no access to other technological resources (e.g., internet and cellular service). The electricity is primarily used to operate water pumps that source water from either (1) a nearby polluted river or (2) contaminated and ill-maintained wells in and around the village. Since these are the only two sources of water for Eli and his family, they are highly prone to water-borne diseases.

   Any questions related to the problem statement were answered before moving to the requirements identification stage

1. Identify problem requirements (25 min): Next, participants were asked to generate problem requirements based on the problem statement. Specifically, participants were asked to generate up to five problem requirements and use the Analytical Hierarchy Process (AHP) Chart to organize and rate the level of importance of each requirement.

2. Concept Generation (15 min): Next, participants were asked to individually ideate solutions to the given problem statement. They were asked to generate as many solutions as they had time for by sketching their solution and describing their solutions using text. Participants were also asked to record the strengths and weaknesses of each solution.

3. Concept Evaluation and Selection (15 min): Upon completing the initial ideation stage, participants were asked to use a concept scoring matrix to select one final idea to move forward with.

On the second day of the workshop, participants were asked to evaluate their proposed final solution. Specifically, participants were given the ten sustainable design heuristics proposed by Blevis [74] and were asked to rate how well their solution utilized these heuristics. Participants were provided a 5-point scale with 1 = “Very Poor” and 5 = “Very Good” to make these evaluations. The participants’ evaluations of the sustainability of their solutions were used to answer RQs 2 and 3. We used the participants’ self-evaluations as a proxy for their use of sustainability in the design process because concept evaluation and selection play a critical role in determining the success of the engineering design process [76]. Therefore, understanding participants’ concept evaluation decisions can reveal important insights into the potential outcomes of their design process [77]. However, we acknowledge that the use of self-evaluations is a potential limitation of this study since self-reported measures are prone to measurement error [78]. Therefore, future research will test the accuracy of students’ self-evaluations when compared to external expert evaluations.

Upon completing the final solution evaluations, all participants were asked to complete a post-intervention survey. The survey consisted of the same 28-item IRI and the 25-item survey on sustainability attitudes, beliefs, and intentions (Sec. 4.2.1). After participants completed the survey, the workshop was concluded with an in-class discussion on the topic of sustainability.

It should be noted that one of the authors (EMS) was the instructor for the two sections of the course in which the study was performed. Since the experiment was conducted as a module in the overall semester-long course, the instructor executed all the steps in the experiment. The instructor’s presence in the classroom could have introduced unexpected effects during the execution of the experiment (e.g., performance expectation from the students) and in the analysis of the results. We tried to mitigate these effects by having the other two authors (RP and MAA) present during most of the experiment, which was conducted over Zoom. Additionally, we emphasized at the beginning of the experiment that although the module was part of the overall course, the use of the students’ data was completely optional and that their decision to participate in the study would not be revealed to the instructor until after the semester was over and the grades were released.

The data collected in the experiment were analyzed using statistical techniques. The details of the analyses used to answer each RQ, and the corresponding results are discussed in the remainder of this section. It should be noted that of the 40 participants who consented to the study, only 38 (Group A = 20, Group B = 18) completed the pre- and post-intervention surveys, and the data from this subset were used for the analyses.

We hypothesized that students would report an increase in their beliefs, attitudes, and intentions toward sustainability after participating in the workshop, but not necessarily in their trait empathy. To test this hypothesis, a series of two-way mixed ANOVAs were performed with the participants’ survey responses as the dependent variables, time (i.e., pre- and post-intervention) as the within-subjects factor, and treatment group (i.e., the introduction of the sustainable design lecture) as the between-subjects factor. It should be noted that five out of 28 subsets in the data violated the assumption of normality as assessed using the Shapiro–Wilk test; however, we chose to perform the test despite the violation given the robustness of the ANOVA [79,80]. Additionally, there were no extreme outliers in the sample (± 3 interquartile range). From the results summarized in Table 1, Figs. 2 and 3, we see that while participants reported a significant decrease in their feeling of personal distress, they reported significant increases in their beliefs and intentions toward taking sustainable actions. These results partially support our hypothesis, and the implications of these results are discussed in Sec. 6.1.

To answer the second research question, a series of Mann–Whitney U Tests were performed with the participants’ self-evaluated sustainability of their solutions as the dependent variable and the treatment group (i.e., the introduction of the sustainable design lecture) as the independent variable. As a reminder, participants in Group A received the sustainable design lecture before the design activity, whereas participants in Group B received the lecture after the design activity. From the results, summarized in Table 2, we see that participants from Group A, i.e., those who received the lecture before the design activity, reported higher scores with disposal (p < 0.06), salvage (p < 0.06), and recycle (p < 0.02). On the other hand, participants from Group B reported higher scores with “sharing for maximal use” (p < 0.09). The implications of these findings are discussed in Sec. 6.2.

To answer the third RQ, we computed a series of linear regression models with the participants’ self-evaluated sustainability evaluations on the ten sustainable design heuristics as the dependent variable. We used the four components of the participants’ post-intervention IRI responses (i.e., perspective-taking, fantasy, empathic concern, and personal distress) and the three components of the attitudes toward sustainability scale (i.e., beliefs, attitudes, and intentions) as the predictors while controlling for the treatment group (i.e., the introduction of the sustainable design lecture). Additionally, we performed a sensitivity-based power analysis using G*power [81] to identify effect sizes of interest, given error probability α = 0.1, power = 0.70, and sample size = 38. These criteria for α and power were chosen given the exploratory nature of the study. Based on the power analysis, effect sizes in the range of R² = 0.22 were considered to be of interest for trait empathy, and R² = 0.20 for the attitudes toward sustainability.

From the results (see Tables 3 and 4), we see that participants’ trait empathy predicted their self-evaluations on the metrics of disposal, recycling, and finding wholesome alternatives. Among the four components of trait empathy, strong correlations (|β_std.| > 0.25) were observed between (1) empathic concern and disposal (positive), (2) personal distress and disposal (negative), (3) perspective-taking and finding wholesome alternatives (positive), (4) personal distress and finding wholesome alternatives (positive), and (5) fantasy and finding wholesome alternatives (negative). On the other hand, attitudes toward sustainability did not predict the self-evaluations of their solutions. These results partially support our hypotheses, and the implications of these results are discussed in Sec. 6.3.

Our aim in this research is to investigate the influence of designers’ internal and interpersonal traits—specifically, their trait empathy and their beliefs, attitudes, and intentions toward sustainability—on the self-evaluated sustainability of their solutions. Three key findings were observed from the results of the experiment:

1. Participants reported an increase in their beliefs and intentions toward sustainability and a decrease in personal distress from before to after participating in the sustainable design workshop.

2. Participants who received the sustainable design lecture first reported higher self-evaluations of their solutions in terms of disposal, salvaging, and recycling.

3. Participants’ trait empathy predicted the self-evaluated sustainability of their solutions in terms of disposal, recycling, and finding wholesome alternatives.

The implications of these findings are discussed next.

The first key finding from the results is that participants’ beliefs and intentions toward sustainability significantly increased from before to after participating in the workshop, partially supporting our hypothesis. The increase in participants’ beliefs about sustainability could be attributed to the new knowledge that students gained through the sustainability lecture. Moreover, the increase in intentions toward sustainable action could be attributed to the use of the design task in the workshop. The design task could have allowed participants to practice sustainable design by improving access to clean water, thereby exploring UN SDG #6. This experience could have, in turn, resulted in increased confidence in participants’ tendency to act sustainably in the future. This finding corroborates prior findings highlighting the higher effectiveness of design tasks in sustainability education [28], and the importance of incorporating social and environmental contexts in human-centered design activities [19]. Furthermore, in the design task, participants were introduced to the design problem using a persona. The use of a persona could also have made the design task more effective in increasing students’ intentions toward sustainability, as suggested by Carey et al. [82]. However, future research should further investigate how variations in the different aspects of the design task (e.g., the problem context and persona) influence these changes.

On the other hand, we see a significant decrease in participants’ personal distress tendencies and a lack of change in their perspective-taking, fantasy, and empathic concern tendencies. This finding resonates with similar results where students’ personal distress decreased over an eight-week engineering design project [17]. Moreover, researchers have also found that students’ personal distress tendencies negatively relate to the number of ideas generated by them in engineering design [50]. The decrease in participants’ personal distress tendencies could be attributed to an improvement in their emotion regulation skills [83] since prior work suggests that personal distress tendencies relate to one’s emotional vulnerability [84] and empathic over-arousal [85]. However, students’ emotional responses to the problem statement were not tested in this study and could be an exciting direction for future work.

The second key finding from our results is that the introduction of the sustainable design lecture influenced participants’ self-evaluated sustainability of their solutions. Specifically, participants who received the sustainable design lecture before the design activity reported higher self-evaluations of their solutions in terms of disposal, salvaging, and recycling. This finding suggests the effectiveness of the sustainable design lecture in encouraging the use of sustainability heuristics and generating solutions that better utilize these heuristics. While previous research by Lagun Mesquita and Missimer [33] reported that student designers found it difficult to incorporate aspects of sustainability in the product design process, the results from this paper were promising showing that students were able to better incorporate sustainable design heuristics.

The higher self-evaluations of solutions by participants who received the lecture first could be attributed to the additional opportunity that these participants had to apply the sustainability heuristics in their solutions, therefore, learning by doing [86]. That is, introducing the lecture first could have resulted in participants applying these heuristics in their solutions, in turn, leading to higher self-evaluations. In contrast, participants who received the lecture after the design activity did not have the opportunity to apply these concepts in their solutions. These findings further encourage the development of interventions such as short-form workshops and lectures to reinforce the integration of sustainability concepts in engineering design. However, given the self-reported nature of the assessments of the solutions, future research is warranted to assess the accuracy of participants’ self-evaluations of their solutions, potentially through the use of external expert evaluations and objective evaluation tools (e.g., those employed by [71,87]).

The final key finding is that participants’ trait empathy significantly predicted the self-evaluated sustainability of their solutions evaluated in terms of disposal, recycling, and finding wholesome alternatives. Specifically, a strong positive relationship was observed between (1) empathic concern and disposal, (2) perspective-taking and finding wholesome alternatives, and (3) personal distress and finding wholesome alternatives (positive). These findings suggest that certain empathic traits (i.e., empathic concern, perspective-taking, and personal distress) could support designers to generate more sustainable solutions and effectively integrate sustainable design into the engineering design process. Furthermore, these findings reinforce prior work arguing for the need for interpersonal competencies, in particular, empathy, toward effective sustainable design [36]. These results are also promising as they indicate that participants relied on both, the cognitive (i.e., perspective-taking) and affective (i.e., empathic concern, personal distress) components of their trait empathy [88]. This finding is particularly important as Hess and Fila discuss that both cognitive and affective components are important and are needed to help designers better understand end-user's needs.

Another important finding is that participants’ fantasy tendencies are negatively related to the self-evaluated sustainability of their solutions in terms of finding wholesome alternatives. This finding could be attributed to the contextual nature of this heuristic—i.e., finding wholesome alternatives relies on one’s knowledge of possible alternatives and materials available in the region of interest. Designers with high fantasy tendencies—i.e., those who can more effectively relate to fictitious individuals and situations [48]—could have identified more opportunities to find wholesome alternatives and, in turn, could have been more critical of their solutions’ inability to utilize this heuristic. However, in making this inference, we assume that participants generated solutions that did not effectively employ this heuristic, further emphasizing the need for future work on the accuracy of participants’ self-evaluations. Furthermore, this inference calls for future research into the contextual nature of the various sustainable design heuristics and the role of problem definition and context on designers’ learning and performance. Taken together, these findings support prior arguments emphasizing the need for empathy development in sustainable design education.

Our aim in this research was to investigate the relationship between designers’ individual differences—in particular, trait empathy and beliefs, attitudes, and intentions toward sustainability—and the self-evaluated sustainability of their solutions. From the results, we see that participants reported an increase in their beliefs and intentions toward sustainability from before to after participating in the workshop. We also see that participants who received the sustainable design lecture before the design activity reported higher self-evaluations of solutions in terms of disposal, salvaging, and recycling. Finally, participants’ trait empathy significantly predicted the self-evaluated sustainability of their solutions evaluated in terms of disposal, recycling, and finding wholesome alternatives. These findings highlight the need for future research in sustainable design and education to focus on designers’ empathy development.

Although the findings of our study provide important insights into the relationship between sustainable design and students’ empathy, our study has several limitations. First, we used participants’ self-evaluations of the sustainability of their solutions. The use of self-evaluations could have resulted in potential biases in the scores given novice designers’ tendencies to over- and under-estimate their performance ability [78]. Specifically, self-evaluations could be prone to ownership biases [89–91], which lead designers to overestimate the merits of their ideas in addition to self-serving biases which lead designers to create a more favorable image of themselves by providing a high rating to their ideas [92–94]. Future work must, therefore, extend this research to assess participants’ solutions using external experts and objective evaluations (e.g., using measures employed by Ross et al. [87] and She and MacDonald [71]). This direction of work could also extend beyond environmental sustainability and look at the social sustainability of solutions through measures such as those developed by Rainock et al. [95]. Furthermore, such an investigation could test the relationship between environmental sustainability and other ideation effectiveness measures such as creativity [96] and innovativeness [97,98]. This line of investigation could also inform the development of decision-making tools that could support novice designers in making trade-off decisions, particularly in the context of sustainable design [21].

Second, the workshop was conducted in the second half of the semester when students were completing their semester-long design projects. This could have resulted in students not seeing great value in the intervention (e.g., see work by Prabhu et al. [99]). Future research must extend our findings to study the effects of the timing of the intervention in the semester and in relation to their semester-long projects. Third, the lecture was given as part of the workshop primarily focused on sustainable design, and no special emphasis was given on the relationship between sustainable development and empathy. Future research must investigate how the educational intervention could be formulated to support empathy development, especially directed toward social and environmental sustainability. This direction of research must also investigate motivational components of empathy as explored by Weisz and Zaki (2018) [100]. Finally, a within-subjects study design was used in this research, without the use of a control group. Future research must compare the effects of the lecture-based intervention to one without the lecture to isolate the effects of the two components of the workshop, i.e., the design task and the lecture.

An earlier version of this paper was presented at the 2021 Design Education Conference at the ASME International Design Engineering Technical Conferences [101]. We would also like to acknowledge the thoughtful and detailed feedback from the reviewers—their feedback has helped us significantly improve the quality of this paper

There are no conflicts of interest.

The data sets generated and supporting the findings of this article are obtainable from the corresponding author upon reasonable request.