Consumption Behavior
The influence of visual impact messages on pro-environmental consumption behavior and intentions, and the mediating role of awareness of consequences, feelings of responsibility and
response efficacy beliefs
Master’s Thesis Persuasive Communication | University of Amsterdam Supervisor: Dr. M.H.C. Meijers
Student: Amber van Tussenbroek (10358218) Date: 28 June 2019
Abstract
Although many people care for the environment, they have difficulties to make more pro-environmental choices. They might be reluctant to do so because they lack awareness of the consequences of their environmental behavior, which subsequently leads to a lack of feeling responsible for environmental problems and the belief that their behaviors do not make a difference (i.e. low response efficacy beliefs). Therefore, this study aimed to investigate whether these barriers to pro-environmental behavior can be overcome by using visual impact messages. The research experimentally tested (N = 94) if a visual impact message (vs. verbal impact message), that let people directly experience the consequences of their choices, could increase pro-environmental consumption behavior and intentions. In addition, the study tested if this proposed effect was mediated by the sequential process of environmental beliefs (awareness of consequences, feelings of responsibility, and response efficacy beliefs). The results show that a visual impact message (vs. verbal impact message) leads to stronger pro-environmental consumption behaviors. However, message type did not influence pro-environmental consumption behavior intentions. Besides, message type did not influence awareness of consequences, and therefore the effect of visual impact messages was not mediated by awareness of consequences, feelings of responsibility and response efficacy beliefs. Despite this, awareness of consequences did lead to feelings of responsibility, which in turn led to response efficacy. This confirmed the causal chain of environmental beliefs, that in turn led to pro-environmental consumption behavior intentions. The findings of this study provide insights into the influence of visual impact messages on environmental behavioral change, with the main conclusion that visual impact messages can lead to stronger pro-environmental behavior, but the underlying process needs further research.
Key words: visual impact, awareness of consequences, feelings of responsibility,
Introduction
Nowadays, environmental issues are a heavily debated topic. More and more people seem to be convinced that something must be done about the environment (Steg, Bolderdijk, Keizer, & Perlaviciute, 2014). Despite this, people in Western societies still live beyond their ecological means. Last year, in 2018, the Earth Overshoot day was on August 1. According to Global Footprint Network (2019), this day marks the date when humanity’s consumption and production behavior has reached the level of what the Earth’s ecosystems can regenerate that year. In other words, that day humanity has used all its ecological resources that the Earth can reproduce in one year. Last year was the earliest date since the world first went into ecological overshoot in 1970. This confirms that more measures must be taken to solve the environmental problems.
For years environmental organizations and governments have been trying to encourage people to be more environmentally aware (Bulkeley, 2005). For example, last year the European Union agreed to ban plastic straws, cutlery, plates and other plastic products from 2021 (European Commission, 2019). Although this is a step in the right direction, much more is needed. Not only environmental organizations and governments but also people themselves are responsible for the environment.
However, people often have difficulties to behave in an environmentally friendly way, which can be explained by the absence and abstraction of immediately perceivable consequences of their behavior (Barr, Gilg, & Shaw, 2011; Lorenzoni, Nicholson-Cole, & Whitmarsh, 2007). For this reason, individuals lack awareness of the consequences of their environmental behavior which subsequently leads to a lack of feeling responsible and a lack of environmental response efficacy beliefs (Cleveland, Kalamas, & Laroche, 2000; Doherty & Webler, 2016). Thus, raising people’s awareness of consequences will eventually lead to pro-environmental behavior and intentions (Stern, Dietz, Abel, Guagnano, & Kalof, 1999; Doherty & Webler, 2016). Therefore, it is important to find effective communication tools to make people aware of the consequences of their
consumption behavior. A possible way to achieve this is through the use of visual impact messages.
Visual messages of the impact on the environment have the quality to make abstract information more concrete (O’Neill, Boykoff, Niemeyer, & Day, 2013; Sheppard, 2005). It demonstrates that individuals can make a difference by immediately visualizing the impact of their environmental behavior. Previous research has shown that such visualizations can result in stronger pro-environmental behaviors and intentions (Ahn, Bailenson, & Park 2014; Ahn, Fox, Dale, & Avant, 2015; Bailey et al., 2015). In addition, it has been demonstrated that visual impact messages are more persuasive because they stimulate higher elaboration (Sheppard, 2005). Therefore, the aim of this research is to investigate whether the barriers to pro-environmental behavior can be overcome using visual impact messages. All things considered, this study is focused on answering the following research question:
‘’In what way do visual impact messages influence pro-environmental consumption behavior intentions and pro-environmental consumption behavior, and is this effect mediated by awareness of consequences, feelings of responsibility and response efficacy beliefs?
This study contributes to the research field of environmental behavioral change and environmental communication. Studies show that awareness of consequences, feelings of responsibility, and response efficacy beliefs are strong predictors for environmental behavior (Doherty & Webler, 2016; Stern et al., 1999). But how this may be stimulated is largely understudied. The findings of this study may as such contribute to the research on environmental communication and provide insights in how awareness of consequences, feelings of responsibility, and response efficacy beliefs may be stimulated. Finally, this research may help policymakers to increase society's pro-environmental consumption behavior when developing campaigns, which
stimulate sustainable choices and behavior. This could eventually lead to the mitigation of environmental issues and preservation of the world’s ecosystems.
Theoretical framework
Environmental beliefs
Although many people care for the environment, they have difficulties to make more pro-environmental choices (Lorenzoni et al., 2007; Meijers, Remmelswaal, & Wonneberger, 2018). This value-action gap can be explained by the complexity of the human-environment relationship (Jamieson, 2006). For many people, environmental issues, such as climate change, are perceived as distant and abstract, which makes it difficult to relate an individual’s consumption behavior to environmental consequences (Barr et al., 2011; Lorenzoni et al., 2007). Therefore, it is crucial to raise consumer’s awareness of consequences when it comes to achieving pro-environmental behavior (Doherty & Webler, 2016; Han, 2015). Awareness of consequences in this study is a person’s awareness of the adverse environmental consequences that consumption behavior poses (Doherty & Webler, 2016). According to the value-belief-norm (VBN) theory, an individual's environmental behavior can be explained by a sequential process of ecological worldview, awareness of consequences, and feelings of responsibility for the problem (Stern et al., 1999; Doherty & Webler, 2016). By making people aware, it can make them feel responsible for these ecological consequences (Stern et al., 1999; Doherty & Webler, 2016; Klöckner, 2013). Society often beliefs that the government, industries and businesses are responsible for the environmental problems (Lorenzoni et al., 2007). However, also individuals contribute to these problems. For example, with their consumption behavior. What, how, and how much they consume has a direct impact on the environment (Trudel, 2018). In addition, consumers generally underestimate the actual amount of what they consume (Attari, Dekay, Davidson, & de Bruin, 2010). Being aware of the environmental
consequences can motivate people to gather information about the causes of environmental problems, which in turn can lead to feelings of responsibility for environmental problems (Cleveland et al., 2005; Truelove, 2009). Based on previous studies, which confirm the VBN’s causal chain of influence, it is expected that awareness of consequences influences feelings of responsibility (Stern et al., 1999; Doherty & Webler, 2016; Klöckner, 2013).
In the VBN model, ascription of responsibility indicates the feelings of responsibility for the negative consequences of not acting environmentally friendly (De Groot & Steg, 2009; Doherty & Webler, 2016). It has been demonstrated that individuals with a greater feeling of personal responsibility are more likely to engage in pro-environmental behaviors (Doherty & Webler, 2016; Kaiser, Rannet, Hartig, & Bowler, 1999; Kollmuss & Agyeman, 2002). Furthermore, feeling responsible for environmental problems indicates knowledge of the causes of these problems (Doherty & Webler, 2016). This, in turn, influence efficacy beliefs (Bandura, 1986). For example, the belief that individuals are mainly causing environmental problems can lead to the belief that individuals have the ability to reduce it. In other words, it can lead to stronger response efficacy beliefs (Bandura, 1986). Previous research provides evidence for this relationship (Doherty & Webler, 2016; Kollmuss & Agyeman, 2002; Truelove, 2009).
In addition, response efficacy beliefs can be crucial factors in the initiation, maintenance, and outcome of behavior (Bandura, 1986). According to the social cognitive theory, people who believe their behavior will contribute to desired outcomes (i.e. high personal response efficacy) are expected to put more effort into initiating, accomplishing and maintaining that behavior than people with low personal response efficacy (Bandura, 1986). The expanded VBN model and other studies have shown that pro-environmental behavior (and behavioral intentions) are likely to increase when people’s response efficacy beliefs are high (Doherty & Webler, 2016; Izagirre-Olaizola, Fernández-Sainz, & Vicente-Molina, 2015; Meijers et al., 2018). Furthermore,
previous research suggests that pro-environmental actions are not only driven by beliefs about the impact of actions at the individual level, but also at the group level (Doherty & Webler, 2016). Many environmental problems are observed as collective problems, which need collective solutions (Doherty & Webler, 2016). Therefore, this study also focuses on personal response efficacy and collective response efficacy (an individual’s belief that a group’s behavior produces desired outcomes Riggs & Knight, 1994).
The integration of various theories and factors within the VBN model enable it to be a strong predictor of pro-environmental behavior (Doherty & Webler, 2016; Stern et al., 1999; Stern, 2000). Thus, the environmental beliefs: awareness of consequences, feelings of responsibility and response efficacy beliefs need to be stimulated. However, the question how to increase the sequential process of awareness of consequences, feelings of responsibility and response efficacy beliefs is largely understudied. A possible approach to increase these environmental beliefs is the use of visual impact messages.
Visual impact messages
Messages employing visualizations of the impact of individual’s actions, make it possible to directly experience the consequences of their behavior by giving feedback in real time (Ahn et al., 2015). An example of visual impact messages in the health domain are the images on cigarette packs, which show possible future consequences of smoking behavior. Research showed that this visual feedback caused people to think more about the future consequences of their behavior (Thrasher, Hammond, Fong, & Arillo-Santillán, 2007). Because of this feedback function, it is expected that visual impact messages simplify the link between individual environmental behavior and its future consequences (Lorenzoni et al., 2007). It is especially needed to simplify this link since the effects of pro-environmental behavior are not directly measurable and demand a lot of effort from individuals. Besides, it contributes to the collective effort. Therefore, present-day actions will usually not have an immediate visible effect on the environments. This makes it difficult for
individuals to be aware of the consequences of their actions, comprising a major obstacle for pro-environmental behavior (Doherty & Weber, 2016; Lorenzoni et al., 2007; O’Neill & Nicholson-Cole, 2009). Therefore, it is suggested to develop communications tools that use visual feedbacks, so that people immediately experience the effects of their behaviors. A visual impact message is such a communication tool. Since it provides real-time feedback, it enables it to reduce the spatial distance between an individual’s environmental behavior and their impact on the environment (Lorenzoni et al., 2007). It is notable that research is still scarce around the usage of visual impact messages and their potential to influence people’s environmental beliefs and promote pro-environmental behavioral change. However, there are some studies that used virtual reality to develop such visual impact messages, which triggered pro-environmental behaviors (Ahn et al., 2014; Ahn et al., 2015; Bailey et al., 2015).
For example, in the study of Bailey et al. (2015), a visual impact message was used to reduce energy consumption related to hot water. With virtual reality they let participants experience a shower in which they received feedback on the amount of energy they used to heat and transport the water. Energy use in the visual feedback condition was represented by showing the amount of individual pieces of coal that were used, in which one piece of coal was equal to 15 seconds of shower and 100 watts of electricity. While the other condition gave only textual feedback telling how many pieces of coal was used. Participants in the visual condition used cooler water compared to the condition that only used text. The visual condition of images of coal may have made the consumption of coal more evident. Thus, this study showed that a visual impact message made it possible to provide real-time feedback of the user’s actions. In this way, it is easier to link individual behavior to future consequences (Bailey et al., 2015). In another study, a visual impact message was developed to reduce paper consumption. Results showed that the virtual experience of cutting down a tree (after reading that it takes half a tree each year to provide one individual with toilet paper) made the participants consume 20% less paper compared to the participants who simply read about cutting down a tree (Ahn et al., 2014). Thus, the visual
feedback on toilet paper usage is reflected by seeing the trees being cut and its impact on the environment. This high level of feedback of an individual’s action is likely to have a persuasive effect on environmental behaviors.
It is expected that this feedback function increases the degree of consumer’s knowledge about environmental consequences. Hence, it can be assumed that by using visual impact messages a greater awareness of consequences will be achieved because the consequences of people’s action(s) are directly visualized. So, a visual impact message has the ability to make an abstract environmental problem more concrete (Bailey et al., 2015). In a way that the abstract relationship between buying products in the supermarket and the effects on the environment (it might have later) becomes clearer. Thus, it makes the effects of an individual’s action clearer, which also shows that people are responsible for the environmental issues. Therefore, it is assumed that a visual impact message can increase feelings of responsibility. In addition, a visual impact message provides feedback that people are able to reduce the threat to an environmental problem by visualizing the effect of an individual’s action. By illustrating that their pro-environmental behaviors do make a difference, consumer’s response efficacy beliefs will increase.
To sum up, messages communicating environmental impact increase pro-environmental behavior and intentions (Ahn et al., 2014; Ahn et al., 2015, Bailey et al., 2015). The question is if this effect is due to the textual feedback that is offered or to the added visualization of the feedback. Taking previous research into account, it can be said that a visual impact message compared to a verbal impact message will have a greater persuasive effect, as visual information can bring cognitive and affective information at a glimpse (Messaris, 1997). Below, this will be further discussed.
Visual impact message versus verbal impact message
It is well known that images overpower words with their message persuasiveness (Messaris, 1997). Visual representations are therefore also used as effective communication tools since the
human brain tends to process visuals much faster than texts (Messaris, 1997; Lazard & Atkinson, 2014). The ability of images to elicit immediate cognitive and effective reactions ensures immediate visceral understanding in a way that text cannot (Green & Myers, 2010). As they say, a picture tells a thousand words. Visual representations make abstract concepts more concrete and may motivate people to further inspect the message information, allowing for higher elaboration (Sheppard, 2005). Therefore, visuals have become essential for environmental communication (O’Neill & Smith, 2014).
It is supported that images of environmental impact promote behavioral change, especially when it is coupled with verbal information (O’Neill et al., 2013). A possible explanation for this could be that when the visual and verbal system of the brain is activated, the additive effect generates better results than when only the verbal system is activated (Paivio, 1991). Meaning that messages with visuals and text enable the brain to process and assimilate information more effectively (Sheppard, 2005). Especially, images can aid in textual learning because it enables individuals to experience consequences which cannot be seen directly in the real world. Therefore, environmental impact visuals have the ability to make the invisible visible, the abstract concrete, and the long-term effects of an individual’s environmental behavior appear nearer (Sheppard, 2005). So, it gives the opportunity to provide a high level of feedback about the choices people make.
As stated before, it is expected that this high level of feedback has the potential to raise people’s awareness of the environmental consequences of their consumption behavior, which in turn increases feelings of responsibility and response efficacy beliefs. All things considered, it is more likely that combining verbal information and visual content regarding environmental impact in a message (i.e. visual impact message) could result in stronger pro-environmental consumption behavior and intentions than when only verbal information (i.e. verbal impact message) is used. Therefore, the following hypothesis is proposed:
H1: A visual impact message (vs. verbal impact message) increases (a) awareness of consequences, (b) feelings of responsibility, and (c) response efficacy beliefs which subsequently increases (d) pro-environmental consumption behavior and (e) pro-environmental consumption behavior intentions
Figure 1. Conceptual model
Methods
Participants and design
The research question will be answered by conducting an online experimental study with single factor between-subjects design including two levels (message type: visual impact message vs verbal impact message). Participants were approached via social media messaging. The participants were required to speak Dutch and to be at least 18 years old. In total, a convenience sample of 128 participants voluntarily took part in the online study. Participants who did not complete the experiment (n = 18) were excluded from the analyses. Because participants had to choose between different food products in the experiment, participants who were vegetarian (n = 8), allergic for certain food products (n = 2), and who did not eat certain food products (n = 6) were excluded as well. In the end 94 participants were included in the analyses (NVisualImpactMessage = 42, NVerbalImpactMessage = 52). The sample of participants consisted of 41.5% female and 58.5% male,
with a mean age of 33.67 (SD = 14.85). Because 42.6% has completed or is currently doing a master’s degree, 13.85% bachelor’s degree and 30.9% higher vocational education, the sample was relatively highly educated.
Procedure
The experiment was conducted online using Qualtrics. When starting the experiment, participants would first read a brief instruction, which explained the procedure of the experiment. After this, participants provided their consent for participating in the experiment. Thereafter, participants were randomly assigned to one of the two conditions. In both conditions, it was explained that the participants had to imagine that they were in a supermarket and that they were going to do some grocery shopping and had to decide which product (out of three options) they would like to buy in a certain product category (e.g. milk, fish). In total there were six product categories and the products within these categories differed in their environmental friendliness. The choices participants made, measured pro-environmental behavior. Participants could view the products in the product category as long as they want, but with a forced minimum exposure of 5 seconds. Afterwards, participants filled out questions regarding the proposed mediators: awareness of consequences, feelings of responsibility, response efficacy beliefs, and the dependent variable pro-environmental consumption behavior intentions. Then, participants answered questions that probed their demographics and food preferences. Hereafter, participants were asked if they could see the images clearly and they could leave comments about the experiment. Finally, after completing the survey, participants were thanked for their participation.
Stimulus material
In both conditions, participants were exposed to six different product categories which existed of three product choices (Appendix C). In each product category, the products were positioned from
the biggest to the smallest impact on the environment. Each product choice consisted of an image of the product and text which described what the product contains and what the environmental impact of this is. For example, the peanut butter category: the first option had the biggest and the most negative impact on the environment. The text explained that the product contains palm oil and that this contributes extremely to deforestation. The second option had a medium negative impact on the environment. The text explained that this product contains sustainable palm oil, which has a moderate contribution to deforestation. The third option had no (negative) impact on the environment. The text here explained that this contains no palm oil and that this product does not contribute to deforestation. Thus, every choice in a product category described the link between a product and its environmental impact. The same order of the six product categories was used in both conditions. The difference between the two conditions was that in the visual impact message condition images of environmental consequences had been added. Each product category showed a different environmental problem. For example, the peanut butter category explained the link between palm oil and deforestation. Therefore, the product with the biggest impact showed an image of extreme deforestation, the product with the medium impact showed an image of moderate deforestation and the product with no impact on the environment showed an image of untouched jungle. Another example, the fruit category, within this category a link was made between the transport of the fruit and global warming. Because transport produces a certain amount of CO2 emissions. Therefore, this category showed images from extreme melted ice sheets to none melted ice sheets. Thus, within each product category, each product showed a level of impact on the environment. In this way, each product communicated the product’s environmental impact by visualizing how one’s consumption behavior affects the environment. The environmental images gave feedback in real time by showing which product choice is the best for the environment (i.e. choosing the most environmentally friendly product led to no environmental impact).
Measures
Awareness of consequences
The mediator awareness of consequences was measured with four items on a scale from 1 (completely disagree) to 7 (completely agree): The consumption behavior of people has big consequences, Environmental problems have no effect on me and my family (reversed),
Environmental problems are a threat to society, and Environmental problems are a threat to plants and animals (based on Steg, Dreijerink, & Abrahamse, 2005; Stern et al., 1999). Cronbach’s alpha of the four items was = .71. When deleting the item Environmental problems have no effect on me and my family the Cronbach’s alpha could be enhanced to = .79. However, it was preferred to include all items, because the scale was already reliable. Thus, the four items were used as a measure for the variable awareness of consequences. The higher the score, the higher the participant’s awareness of consequences (M = 5.86, SD = 1.00).
Feelings of responsibility
Also feelings of responsibility was measured with four items on a scale from 1 (completely disagree) to 7 (completely agree): I can also be held responsible for environmental problems, I also have to worry about environmental issues, I feel responsible for environmental problems, and In addition to the government and companies, I am also responsible for environmental problems (based on Antonetti & Maklan, 2014; Steg et al., 2005). The Cronbach’s alpha of all four items together was = .89. The scale was very reliable and could not be improved any further, therefore the four items were constructed for the variable feelings of responsibility. The higher the score, the higher the participant’s feelings of responsibility (M = 5.39, SD = 1.18).
Response efficacy beliefs
The last mediator response efficacy beliefs is measured with four items for personal response efficacy and with four items for collective response efficacy. Both were answered through a 7-
point Likert scale, with answers ranging from completely disagree to completely agree (based on Meijers, Wonneberger, & Azrout, 2019). Personal response efficacy was measured with items like: Environmental problems are partly a result of my own behavior and My personal behavior can contribute to solving environmental problems. Collective response efficacy was measured with items like: If we all reduce the use of environmentally unfriendly products, this will greatly contribute to resolving environmental issues and It is helpful if everyone buys more environmentally friendly products because together, we can protect the environment. Because this study examines the total effect of response efficacy beliefs, the items of personal response efficacy beliefs and collective response efficacy beliefs were combined since it has been found they often correlate (Truelove, 2009). The Cronbach’s alpha of the eight items of response efficacy beliefs was = .89 and could not be improved any further, therefore the eight items were used to measure response efficacy beliefs. The higher the score, the higher the participant’s response efficacy beliefs (M = 5.89, SD = 0.97).
Pro-environmental consumption behavior
The dependent variable pro-environmental consumption behavior was based on product choices in six different product categories. Within each product category one product could be chosen. With the first product having the biggest big, negative impact on the environment, the second product having a medium impact on the environment, and the third the product having hardly or no negative impact on the environment. A sum score for the variable Behavior was constructed with these choices, with a range from 0 to 18. The higher the score, the higher the participant’s pro-environmental consumption behavior (M = 13.38, SD = 2.64).
Pro-environmental consumption behavior intentions
The dependent variable pro-environmental consumption behavior intentions was measured with three items on a scale from 1 (completely disagree) to 7 (completely agree): I intend to take into
account the environmental impact of products when I go shopping for the coming months, I am willing to take the environmental impact of products into account when I go shopping and When I do groceries, I pay attention to the environmental impact of products (based on Ajzen, 2006). Cronbach’s alpha of the three items was = .93, therefore the scale of Intentions was constructed with these three items. The higher the score, the higher the participant’s pro-environmental consumption behavior intentions (M = 4.97, SD = 1.33).
Control variables
During this study, participants were requested to fill in the following demographics: gender (man, woman, other), age (open) and highest or current level of education (none, primary education, pre-vocational secondary education, higher general secondary education, pre-university education, secondary vocational education, higher vocational education, bachelor’s degree, master’s degree, other).
Results
Randomization check
First, to analyse whether participant’s gender, age and highest or current level of education were comparable over the experimental conditions, randomization checks were performed. A Chi-square test was conducted to test the randomization of gender. When comparing the two experimental conditions for gender, results showed that gender was equally distributed over the two conditions χ² (1) = 0.36, p = .548. Hereafter, a One-way ANOVA was conducted to check whether age and education level were also equally distributed over both experimental conditions. Results showed that there was no significant difference between conditions, F (1, 93) = 0.65, p = .422. For education level, a continuous scale had to be created first. Therefore, the last answer Different of this variable was made missing for this analysis. The test showed that education level
was equally distributed over both conditions as well, F (1, 90) = 1.44, p = .234. Therefore, the randomization succeeded.
Direct effects
To test whether there were direct positive effects of message type on pro-environmental consumption behavior and pro-environmental consumption behavior intentions, a PROCESS analysis (model 6; Hayes, 2013) with 5000 bootstrap samples was conducted. Results showed there was a significant relationship between visual versus verbal impact message and behavior, b = 1.70, SE = 0.45, t = 3.85, p < .001 (Figure 1), which means that participants that were exposed to a visual impact message did have a higher level of pro-environmental consumption behavior than participants that were exposed to a verbal impact message. Against expectations, exposure to a visual impact message did not lead to stronger intentions, compared to a verbal impact message, b = 0.34, SE = 0.22, t = 1.51, p = .135 (Figure 2).
The mediating role of environmental beliefs
In hypothesis 1, it was proposed that awareness of consequences, feelings on responsibility and response efficacy beliefs mediate the effect of visual impact message (vs. verbal impact message) on pro-environmental consumption behavior and pro-environmental behavior intentions. A bootstrapping analysis with 5000 samples (using Model 6; Hayes, 2013) did not confirm sequential mediation of message type via awareness of consequences, feelings of responsibility and response efficacy beliefs on pro-environmental consumption behavior (indirect effect = 0.0407, SE = 0.0501, 95% confidence interval [-0.0411; 0.1619]), as well as pro-environmental consumption behavior intentions (indirect effect = 0.0430, SE = 0.0507, 95% confidence interval [-0.0191; 0.1255]). The analysis showed that there was no significant relationship between message type and awareness of consequences, b = 0.23, SE = 0.21, t = 1.10, p = .275, thus H1a was rejected. However, results indicated that awareness of consequences increased feelings of
responsibility, b = 0.59, SE = 0.11, t = 5.48, p < .001, which subsequently led to an increase in response efficacy beliefs b = 0.47, SE = 0.06, t = 7.35, p < .001. This means that higher levels of awareness of consequences may lead to stronger feelings of responsibility, which subsequently lead to stronger response efficacy beliefs. H1b and H1c were thus confirmed.
In hypothesis 1d, it was proposed that response efficacy beliefs would increase pro-environmental consumption behavior. While it was expected that there would be a relation, no significant effect was found between response efficacy beliefs and pro-environmental consumption behavior b = 0.65, SE = 0.36, t = 1.81, p = .073. Thus, a higher level of response efficacy beliefs did not lead to stronger pro-environmental consumption behavior, meaning H1d was not supported.
In the last hypothesis 1e, it was proposed that response efficacy beliefs would increase pro-environmental consumption behavior intentions. The analysis showed a significant relationship between response efficacy beliefs and pro-environmental efficacy beliefs, b = 0.68, SE = 0.18, t = 3.86, p < .001, meaning that higher levels of response efficacy beliefs might lead to stronger pro-environmental consumption behavior intentions. H1e was thus confirmed. The paths and the unstandardized coefficients and standard errors corresponding to these paths are provided in figure 1 and 2. Specific results can be found in Appendix C.
Figure 2. Path diagram showing direct effects and causal paths linking visual versus verbal impact message with
pro-environmental consumption behavior. Notes: Values outside parentheses are unstandardized coefficients; values in parentheses are standard errors; *p <.05, **p <.001
Figure 3. Path diagram showing direct effects and causal paths linking visual versus verbal impact message with
pro-environmental consumption behavior intentions. Notes: Values outside parentheses are unstandardized coefficients; values in parentheses are standard errors; *p < .05, **p <.001
Conclusion & Discussion
The aim of this research was to investigate the effects of visual impact messages versus verbal impact messages on people’s pro-environmental consumption behavior and intentions. A sequential underlying process (i.e. awareness of consequences, feelings of responsibility and
response efficacy beliefs) was proposed for these effects. It was expected that a visual impact message would lead to stronger pro-environmental behaviors and intentions when compared to a verbal impact message. The results of the study showed that a visual impact message increased pro-environmental consumption behavior. Thus, the visual impact message made people adopt a more pro-environmental consumption behavior. However, contrary to expectations, no effect was found for pro-environmental consumption behavior intentions.
To explain the effectiveness of visual impact messages, awareness of consequences, feelings of responsibility and response efficacy beliefs were considered as mediators. Against all expectations, visual impact messages did not lead to more awareness of consequences. Despite this, a higher level of awareness of consequences did increase feelings of responsibility, which subsequently increased response efficacy beliefs – confirming the VBN’s causal chain (Doherty & Webler, 2016; Stern et al., 1999). Thus, people who had a high level of awareness of consequences did feel more responsible for environmental problems and also had stronger beliefs that their actions could contribute to environmental problems. In addition, stronger response efficacy beliefs resulted in stronger pro-environmental behavior intentions (Doherty & Webler, 2016). However, stronger response efficacy beliefs did not subsequently increase pro-environmental behavior. Altogether, the pro-environmental beliefs: awareness of consequences, feelings of responsibility and response efficacy beliefs did not mediate the positive effect of visual versus verbal impact message on pro-environmental consumption behavior.
Thus, it seems that a visual impact message has a stronger effect on pro-environmental consumption behavior but not on pro-environmental consumption behavior intentions. Normally intentions are a predictor for behavior (Ajzen, 1991). However, in this study individual’s pro-environmental consumption behavior was measured by making decisions between different food products, while at the same time participants were exposed to a visual or verbal impact message. After this intervention, it was examined whether people had stronger intentions to perform this behavior again in the future. The results showed that a visual impact message did not lead to
stronger pro-environmental consumption behavior intentions. An explanation could be that people may believe they do not have sufficient knowledge to perform this pro-environmental behavior in the future. In other words, their self-efficacy is low (i.e. an individual’s belief that they are capable of performing a behavior Bandura, 1986). As stated before, the link of an individual’s behavior and the environment is quite complex (Jamieson, 2006; Lorenzoni et al., 2007). Especially consumption behavior, because many different actions (e.g. buying a certain product) in the supermarket have many different effects, making it difficult to know what to focus on. Thus, people generally do not have the knowledge and expertise about the environmental impact of products to make pro-environmental choices themselves (Trudel, 2018). In addition, consumers might not have the intention to adopt a pro-environmental consumption behavior because in a real-life setting there are other factors that may play a role. For example, one of the participants also left the note: I suspect that many respondents, just like me, want to make the most environmentally friendly choices, but in the supermarket, the price tag also plays a role. Thus, it could be that people are less likely to make pro-environmental choices because of the price of the products. However, the aim of this study was to examine whether visual versus verbal impact messages could lead to different outcomes at all, without these external factors. And if such external factors do not play an important role in any other environmental behavior, it means that these visual impact messages might be effective to promote other environmental behaviors.
Furthermore, against expectations, visual impact messages did not lead to a stronger awareness of consequences. A possible explanation for this could be that participants already had a relatively high level of awareness of consequences, leaving little room for improvement. In addition, the information in both messages can be received as new knowledge. So, visualizing this new information does not increase the effect any further because a verbal message could already make people aware of consequences, they did not know yet. For example, a participant in the verbal impact message condition left the note: I did not know the impact of these products. Thus, explaining the impact of food products without visualization (like in the verbal condition)
could already have a great effect on people’s awareness of the environmental consequences of their consumption behavior. They did not know this information at all, which can be perceived as unexpected or as surprising. Unexpected information can motivate people to further process the information, allowing for higher elaboration (Noordewier & Breugelmans, 2013). Therefore, the unexpected information may have a major effect anyway, whether it is only verbal or verbal and visual. Thus, the causal chain of awareness of consequences, feelings of responsibility and response efficacy beliefs did not explain the underlying process of visual impact messages on pro-environmental consumption behavior. This effect may be explained by other underlying processes. For example, emotional factors, such as guilt. The emotional reaction guilt is stronger when an individual experience the adverse consequences of their actions directly (Kollmuss & Agyeman, 2002). Previous research suggested that guilt is a predictor of pro-environmental behaviors (Elgaaied, 2012). Therefore, a recommendation for future research is to investigate other possible mediators, such as guilt.
Overall, the findings of this study are in line with previous research, which showed that visual impact messages are effective in eliciting pro-environmental behaviors (Ahn et al., 2014; Bailey et al., 2015). They showed that the experience of performing environmentally unfriendly behaviors, such as cutting down a tree or consuming coal to heat water in a virtual reality setting, influenced the behavior of paper use or heating up water. The visual impact message of the current study does represent more real-life experiences, in contrast to virtual reality experiences, which may be easier to integrate into the daily lives of the general public. In addition, through the feedback feature of these visual impact messages, people directly experienced the impact of their consumption behavior on the environment, while this impact is generally perceived as far away (Lorenzoni et al., 2007). This is in line with earlier research in the environmental behavior domain, which provided evidence that such direct experiences can lead to pro-environmental behaviors (Joireman, Truelove, & Duell, 2010; Li, Johnson, & Zaval, 2011).
Furthermore, this study contributes to existing research on environmental behaviors by showing that the complex behavior pro-environmental consumption behavior could be influenced through visual impact messages (Ahn et al., 2014; Ahn et al., 2015; Bailey et al., 2018). It also concurs with research showing that awareness of consequences, feelings of responsibility, and response efficacy beliefs are important predictors of environmental behavioral intentions (Doherty & Webler, 2016; Stern et al., 1999). However, it is hardly reported how these environmental beliefs may be increased. This current research tried to fill this knowledge gap by providing tools on increasing pro-environmental consumption behavior and intentions based on awareness of consequences, feelings of responsibility and response efficacy beliefs via visual impact messages. Therefore, it is recommended that more communication tools should be developed that influence these predictors of pro-environmental behavior and intentions.
Limitations and future research
Some general limitations of this study could be argued. Firstly, the network of the researcher was used to recruit the participants. Even though gender and age were equally distributed, almost all participants were highly educated. This means that the participants did not represent a realistic sample of the population, which did not benefit the external validity of this research. Furthermore, the experiment was conducted online, so people could not be checked during their participation. This could have influenced the results because participants might have been unmotivated, distracted or perhaps under time pressure. Moreover, participants realized that they took part in an experiment, which may have induced them to perceive the message in another way than they would normally perceive. Especially with the environmental beliefs (awareness of consequences, feelings of responsibility, and response efficacy beliefs), it might be that participants responded to this message in a different way by elaborating more with this message than they would normally do in real life. Therefore, for future research, it might be interesting to conduct an actual field study. Finally, it might also be interesting to test various visual and textual materials, as it is suggested
that different types of visuals and texts concerning environmental impact generate different outcomes on pro-environmental behaviors (Hart & Feldman, 2016; O’Neill et al., 2013).
Practical implications
This study also carries practical implications. The current research results showed that visual impact messages can trigger pro-environmental actions. Therefore, they can be used as environmental communication interventions. However, the effects of consumption behavior on the environment are quite complex and the effects of all products contain a lot of information. This might explain why people do not have the belief that they will perform these pro-environmental actions in the future again. Because they do not believe they will have the knowledge to perform this desired behavior (i.e. low self-efficacy). Therefore, it is suggested to install digital screens with these visual impact messages of products in supermarkets. In this way, consumers can be continuously exposed to the impact of products and this might lead to the belief that they can perform this behavior again in the future.
Perhaps, policymakers can use similar visual impact messages to stimulate the future intentions of other environmental behaviors that are less complex. For example, environmental behaviors that mainly consists of one action, such as recycling or water consumption. The surprise of directly experiencing the consequences might remind people of the message even when the message is no longer shown (Dahlén, Friberg, & Nilsson, 2009; O’Neill & Nicholson-Cole, 2009). This is something that can be further investigated by assessing the generalizability of visual impact messages. However, this research is a next step in examining effective approaches to stimulate people in making more pro-environmental choices by visual feedback functions and the results demonstrated that this could be an effective approach to do so.
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Appendices
Appendix A – Information sheet, informed consent and debriefing
A.1 Information sheetGeachte deelnemer
Bedankt voor je deelname aan dit onderzoek. Je gaat meedoen aan een onderzoek dat wordt uitgevoerd onder de verantwoordelijkheid van de Graduate School of Communication Science, onderdeel van Universiteit van Amsterdam.
Het onderzoek gaat over productkeuzes met betrekking tot het milieu. Tijdens het onderzoek krijg je een aantal afbeeldingen van verschillende producten te zien. Ik vraag je deze goed te bekijken en daarna een aantal vragen te beantwoorden. Aan dit onderzoek kunnen enkel deelnemers van 18 jaar of ouder meewerken. Het invullen van de online vragenlijst zal ongeveer 7 minuten in beslag nemen.
Nogmaals dank voor je deelname!
Hartelijke groet,
Amber van Tussenbroek
(amber.vantussenbroek@student.uva.nl)
A.2 Informed consent
Ik verklaar hierbij op voor mij duidelijk wijze te zijn ingelicht over het doel en de methode van het onderzoek en stem bij het starten van de vragenlijst geheel vrijwillig in met deelname aan dit onderzoek. Ik behoud daarbij het recht deze instemming binnen 7 dagen weer in te trekken zonder dat ik daarvoor een reden hoef op te geven en ik besef mij dat ik op elk moment mag stoppen met het onderzoek.
Indien mijn onderzoeksresultaten gebruikt zullen worden in wetenschappelijke publicaties, of op een andere manier openbaar worden gemaakt, zal dit volledig geanonimiseerd gebeuren. Mijn persoonsgegevens zullen niet door derden worden ingezien zonder mijn uitdrukkelijke toestemming.
Als ik meer informatie wil, nu of in de toekomst, dan kan ik me wenden tot Amber van Tussenbroek (amber.vantussenbroek@student.uva.nl). Als ik klachten of opmerkingen heb omtrent dit onderzoek, kan ik contact opnemen met het aangewezen lid van de Ethische Commissie die de ASCoR vertegenwoordigt, te bereiken op het volgende adres: ASCoR secretariaat Commissie Ethiek, Universiteit van Amsterdam, Postbus 15793, 1001 NG Amsterdam; 020-525 3680; ascor-secr-fmg@uva.nl.
0 Ik begrijp de bovenstaande tekst en ga akkoord met deelname aan het onderzoek.
A.3 Debriefing
Je bent aan het einde gekomen van dit onderzoek. Mocht je benieuwd zijn naar de resultaten van dit onderzoek, dan kan je na 2 juli dit opvragen door een bericht te sturen naar amber.vantussenbroek@student.uva.nl.
Heel erg bedankt voor je deelname!
Vergeet niet op het onderstaande pijltje te drukken, zodat alle gegevens opgeslagen worden.
Appendix B – Stimuli material and pro-environmental consumption behavior
questionnaire
B.1 Visual impact message condition
Op de volgende pagina's krijg je een aantal producten in een productcategorie te zien. Stel je voor dat je in de supermarkt bent en iets wil kopen in deze productcategorie.
Bij elk product staat een afbeelding die de milieu impact van het product laat zien. Zo kun je zien wat voor impact jouw keuzes hebben op het milieu.
Bekijk de afbeeldingen en de beschrijvingen goed en maak vervolgens een keuze tussen de producten.
Let op, we zijn geïntereseerd in je eerlijke mening, er zijn dus geen foute of goede antwoorden. Probeer je voor te stellen dat je de keuze in de supermarkt maakt, zoals je dit normaal gesproken ook doet.
Bekijk de producten alsjeblieft goed, want er is geen mogelijkheid meer deze opnieuw te bekijken. Pas na vijf seconden is het mogelijk door te klikken naar de volgende pagina, zodat je rustig de afbeeldingen kunt bekijken. Je kunt net zo lang naar de producten kijken als je wilt.
Welk product zou je kiezen? 0 Calvé pindakaas
0 Whole earth pindakaas
Welk product zou je kiezen? 0 Tomaten in plastic verpakt
0 Tomaten deels in plastic verpakt
Welk product zou je kiezen? 0 Biefstuk
0 Kipfilet
Welk product zou je kiezen? 0 Lychees
0 Druiven
Welk product zou je kiezen? 0 Halfvolle melk
0 Sojadrink
Welk product zou je kiezen? 0 Tonijn
0 Pagasiusfilet
B.2 Verbal impact message condition
Op de volgende pagina's krijg je een aantal producten in een productcategorie te zien. Stel je voor dat je in de supermarkt bent en iets wil kopen in deze productcategorie.
Bij elk product staat aangegeven wat de milieu impact van het product is.
Bekijk de afbeeldingen en de beschrijvingen goed en maak vervolgens een keuze tussen de producten.
Let op, we zijn geïntereseerd in je eerlijke mening, er zijn dus geen foute of goede antwoorden. Probeer je voor te stellen dat je de keuze in de supermarkt maakt, zoals je dit normaal gesproken ook doet.
Bekijk de producten alsjeblieft goed, want er is geen mogelijkheid meer deze opnieuw te bekijken. Pas na vijf seconden is het mogelijk door te klikken naar de volgende pagina, zodat je rustig de afbeeldingen kunt bekijken. Je kunt net zo lang naar de producten kijken als je wilt.
Welk product zou je kiezen? 0 Calvé pindakaas
0 Whole earth pindakaas
Welk product zou je kiezen? 0 Tomaten in plastic verpakt
0 Tomaten deels in plastic verpakt
Welk product zou je kiezen? 0 Biefstuk
0 Kipfilet
Welk product zou je kiezen? 0 Lychees
0 Druiven
Welk product zou je kiezen? 0 Halfvolle melk
0 Sojadrink
Welk product zou je kiezen? 0 Tonijn
0 Pagasiusfilet
Appendix C – Questionnaire
Awareness of consequences
Geef aan in hoeverre je het eens of oneens bent met de volgende stellingen. 1. Het consumptiegedrag van mensen heeft grote ecologische gevolgen 2. Milieuproblemen hebben geen effect op mij en mijn familie
3. Milieuproblemen zijn een bedreiging voor de maatschappij 4. Milieuproblemen zijn een bedreiging voor planten en dieren
1 = Helemaal niet mee eens, 2 = Niet mee eens, 3 = Een beetje niet mee eens, 4 = Neutraal, 5 = Een beetje mee eens, 6 = Mee eens, 7 = Helemaal mee eens
Feelings of responsibility
Geef aan in hoeverre je het eens of oneens bent met de volgende stellingen. 1. Ook ik kan verantwoordelijk gehouden worden voor milieuproblemen 2. Ook ik moet mij zorgen maken om milieuproblemen
3. Ik voel mij verantwoordelijk voor milieuproblemen
4. Naast de overheid en bedrijven ben ook ik verantwoordelijk voor milieuproblemen
1 = Helemaal niet mee eens, 2 = Niet mee eens, 3 = Een beetje niet mee eens, 4 = Neutraal, 5 = Een beetje mee eens, 6 = Mee eens, 7 = Helemaal mee eens
Personal response efficacy
Geef aan in hoeverre je het eens of oneens bent met de volgende stellingen. 1. Milieuproblemen zijn gedeeltelijk een gevolg van mijn eigen gedrag.
3. Door mijn consumptiegedrag aan te passen, kan ik helpen bij het oplossen van milieuproblemen
4. Omdat mijn gedrag van invloed kan zijn op het milieu, maakt het uit of ik milieuvriendelijke producten koop
1 = Helemaal niet mee eens, 2 = Niet mee eens, 3 = Een beetje niet mee eens, 4 = Neutraal, 5 = Een beetje mee eens, 6 = Mee eens, 7 = Helemaal mee eens
Collective response efficacy
Geef aan in hoeverre je het eens of oneens bent met de volgende stellingen. 1. Ik denk dat we door samen te werken milieuproblemen kunnen oplossen 2. Ik denk dat we gezamenlijk milieuproblemen kunnen oplossen door ons
consumptiegedrag aan te passen
3. Als we allemaal het gebruik van milieuonvriendelijke producten verminderen, zal dit enorm bijdragen aan het oplossen van milieukwesties
4. Het is nuttig als iedereen meer milieuvriendelijke producten koopt, want samen kunnen we het milieu beschermen
1 = Helemaal niet mee eens, 2 = Niet mee eens, 3 = Een beetje niet mee eens, 4 = Neutraal, 5 = Een beetje mee eens, 6 = Mee eens, 7 = Helemaal mee eens
Pro-environmental behavior intentions
Geef aan in hoeverre je het eens of oneens bent met de volgende stellingen.
1. Ik heb de intentie om rekening te houden met de mileu impact van producten wanneer ik boodschappen ga doen de komende maanden
2. Ik ben bereid om rekening te houden met de milieu impact van producten wanneer ik boodschappen ga doen
3. Wanneer ik boodschappen ga doen, ga ik letten op de milieu impact van producten
1 = Helemaal niet mee eens, 2 = Niet mee eens, 3 = Een beetje niet mee eens, 4 = Neutraal, 5 = Een beetje mee eens, 6 = Mee eens, 7 = Helemaal mee eens
Control variables
Hieronder volgen wat algemene vragen over jou als persoon en over je voorkeur voor bepaalde producten. Als alle vragen beantwoord zijn kun je door naar de volgende pagina.
• Wat is je geslacht? (Vrouw / Man / Anders) • Wat is je leeftijd? (Open)
• Wat is je hoogst genoten of huidige opleiding? (Geen Basisonderwijs / VMBO / HAVO / VWO / MBO / HBO / WO bachelor/ WO master / Anders)
• Ben je een vegatariër? (Ja / Nee) • Ben je een veganist? (Ja / Nee)
• Zijn er bepaalde dingen die je niet eet? (Nee / Ja, namelijk …) • Ben je allergisch voor bepaalde ingrediënten? (Nee / Ja, namelijk …) • Waren de plaatjes van de producten goed te zien? (Ja / Nee, want …) • Heb je verder nog opmerkingen? (Open)
Appendix D – Figure and table results
Figure 1. Serial multiple mediation model with awareness of consequences, feelings of responsibility, and response
efficacy beliefs as proposed mediators of message type on pro-environmental behavior and intentions.
Table 1
Estimated path coefficients for main effects
Results for mediation effects
Dependent variable Path b SE t p
All outcomes a1 0.23 0.21 1.10 .276 a2 -0.24 0.22 -1.13 .260 a3 0.02 0.13 0.15 .882 a4 0.59 0.11 5.48 <.001 a5 0.31 .08 4.07 <.001 a6 0.47 0.06 7.35 <.001 Behavior b1 0.24 0.28 0.85 .396 b2 0.60 0.27 2.18 .032 b3 0.65 0.36 1.81 .073 c1 1.70 0.45 3.29 <.001
Intentions b1 -0.25 0.14 -1.80 .076
b2 0.29 0.14 2.15 .034
b3 0.68 0.18 3.86 <.001
c1 0.34 0.22 1.51 .135
