Next Article in Journal
Carbon Offset Service and Design Guideline of Tree Planting for Multifamily Residential Sites in Korea
Previous Article in Journal
Buildingmass and Energy Demand in Conventional Housing Typologies of the Mediterranean City
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Promoting Health-related Quality of Life in Minority Youth through Environmental Education and Nature Contact

by
Christine C. Ekenga
*,
Nadav Sprague
and
Damilola M. Shobiye
Brown School, Washington University in St. Louis, Campus Box 1196, St. Louis, MO 63130, USA
*
Author to whom correspondence should be addressed.
Sustainability 2019, 11(13), 3544; https://doi.org/10.3390/su11133544
Submission received: 27 February 2019 / Revised: 23 June 2019 / Accepted: 24 June 2019 / Published: 27 June 2019
(This article belongs to the Section Sustainable Education and Approaches)

Abstract

:
Few studies have examined the relationship between environmental sustainability education and health outcomes in youth. The purpose of this study was to examine health-related quality of life over a 13-week time period in a sample of urban minority youth who participated in an environmental education program with a nature contact component. Health-related quality of life (HRQoL) was measured using a survey comprising five items (physical activity, emotional functioning, school functioning, family support, and social functioning). The overall HRQoL score was determined as the sum of the scores on the five items, with higher scores indicating better HRQoL. A pre-test/post-test within-subjects study design was used to evaluate changes in HRQoL. A total of 53 students (ages 10 to 14 years) participated in the environmental education intervention; 46 (87%) of those students completed HRQoL questionnaires before and after the program. There were statistically significant improvements in overall HRQoL scores and in the family support HRQoL domain scores. Engaging in the natural environment through environmental education may promote HRQoL in youth. Larger, prospective studies are warranted to further investigate these initial findings.

1. Introduction

In the United States, awareness of environmental issues among youth has decreased since the mid-1970s [1]. Nature-deficit disorder, a term coined to describe youths’ decreasing interaction with nature, is thought to be associated with this decline in environmental awareness [2]. Concern about declines in environmental exposure and awareness have led to increased research on environmental education for youth [2,3]. Environmental education studies have examined a variety of outcomes, including whether these educational initiatives influence youth attitudes towards the environment, eco-affinity, environmental knowledge, and whether environmental education increases youth exposure to the natural [4]. Several studies have reported racial and ethnic disparities in environmental awareness and concerns, with white students exhibiting higher levels of eco-awareness than their black counterparts [4].
In addition to disparities in environmental education, there are well-documented racial disparities in access to and contact with nature [5,6,7]. African American youth have been reported to experience less exposure to the natural environment than white youth [4]. There is also evidence that, compared to high-income populations, residents of low-income households and neighborhoods have unequal access to the natural environment [8,9]. These disparities in nature contact may have implications for inequalities in youth behavior, personal skills, and overall health [10,11,12,13]. Nature contact has proven to be beneficial in youth development and social change [10]. Furthermore, there is a growing body of evidence that increasing youth’s nature contact reduces their risk for mental health disorders, such as depression, anxiety, and ADHD, especially among lower socioeconomic groups [14,15,16].
Interaction with nature has shown to be a sustainable and practical method for promoting health as well as better physical, emotional, and mental well-being for youth [10,12,16]. Increased time spent outdoors in nature has been observed to be positively associated with increased physical activity, which in turn reduces health risks associated with inactive lifestyles [17]. Physical activities while being in contact with nature, such as hiking and canoeing, have been associated with greater physical and mental health benefits than traditional forms of exercise [18,19]. Increased time spent outdoors has also been associated with decreased levels of obesity through increased physical activity [19,20,21]. It has also been proposed that nature contact may aid learning and improve social connections [22]. Because adults often facilitate youth’s leisure activities through school and family activities [23], nature contact may improve social connectedness and support at school and at home with family.
When given access to outdoor environmental opportunities, African American and Hispanic youth are able to improve their eco-awareness and environmental knowledge [4]. Thus, it is reasonable to hypothesize that the benefits associated with environmental education may be strengthened by time spent in nature [24]. There is a paucity of studies on the relationships between environmental education and health outcomes in minority youth, including physical, social, and psychological well-being. Here, we present the results of a pilot study designed to evaluate the impact of a nature contact and environmental education program on the well-being of urban minority youth in St. Louis, MO, USA.

2. Methods

2.1. Environmental Education Intervention

An environmental sustainability educational program was developed to expose low-income minority students in St. Louis, Missouri to environmental issues and activities. During the 2017–2018 academic year, the program was administered to students of three elementary schools in the St. Louis Public School (SLPS) District, the largest urban public-school district in the St. Louis metropolitan region. At each of the three schools, more than 95% of students were eligible for free meals through the National School Lunch Program and the School Breakfast Program. The majority of participants in the program were African American (89%) and Hispanic (8%).
The educational program ran continuously throughout the school year and incorporated three key elements: (1) a weekly STEM-based environmental classroom activity, (2) a monthly nature-based outdoor activity, and (3) academic year-round mentoring by local university students. Each week, the university student mentors visited the classroom and taught a hands-on, environmental lesson developed to match the students’ classroom STEM curricula. Table 1 provides an overview of program topics and activities. Weekly topics included ecosystems, geology, agriculture, gardening, sustainability, global warming, and climate change. Four monthly nature-based outdoor outings were created to augment the weekly programming. These nature-based outings included trips to local farms, hiking in state parks, rock climbing, and canoe trips down the Mississippi River. These outdoor adventures not only reinforced classroom learning and provided context for earlier classroom activities, but they also enabled the students to further develop relationships with their classmates and university student mentors, learn outdoor skills, develop leadership skills, develop environmental and conservation awareness, and ultimately change their perception of science and the environment around them.

2.2. Study Design and Participants

A pre-test, post-test study design was undertaken to evaluate health-related quality of life during the environmental education intervention. This design was used because random assignment of students was not possible, as the intervention was administered to students within intact class groups. A 28-item, self-administered questionnaire was administered to youth participants before the commencement of the program (pre-intervention) and after the completion of the program (post-intervention). The questionnaire collected information about age, gender, past environmental science and outdoor activity experiences prior to entering the program, general attitudes towards science, and environmental sustainability awareness. The questionnaire also included validated items about health-related quality of life (HRQoL) [25,26,27]. The questions evaluated HRQoL in five domains: physical activity, emotional functioning, school functioning, social functioning, and family support. Responses to these questions were assessed using 5-point Likert-type scales ranging from 1 to 5, with lower scores indicating better HRQoL.
A total of 53 SLPS students participated in this pilot study. Data were collected from January 2018 to May 2018 (Spring semester 2018), and the mean time between pre- and post- intervention survey administration was 13 weeks. The Institutional Review Board at Washington University in St. Louis deemed the study exempt from review, as youth questionnaire data were de-identified prior to analysis.

2.3. Statistical Analysis

HRQoL items were reverse-scored and transformed to a 0–100 linear scale (1 = 100, 2 = 75, 3 = 50, 4 = 25, 5 = 0), so that higher scores indicate better HRQoL. An overall score was determined by summing the scores of all five domains. Mean and median scores were determined for each of the five domains and the overall score. For each domain and the overall score, the Wilcoxon signed-rank test was used to determine whether there was a significant change in scores from pre-intervention to post-intervention. All tests were two-sided, and a p-value of less than 0.05 was considered to indicate a statistically significant difference. All statistical analyses were conducted using SAS version 9.4 (SAS Institute Inc., Chicago, Il, USA).

3. Results

3.1. Participant Characteristics

A total 53 students, ranging from 10 to 14 years old, participated in the program during the study period. Approximately 96% of the population were racial/ethnic minorities, and 60% of the study population were female. All participants completed the pre-intervention questionnaire; however, seven participants did not complete the post-intervention questionnaire (Table 2).
Figure 1 presents the environmental science and outdoor activity experiences in the past year prior to the pre-intervention questionnaire. Before the environmental education intervention, approximately 49% of the students had not visited a zoo, 32% had not visited a science museum, 20% had not visited a park, 45% had not visited a garden in the past year, and 66% of the students had not met a scientist.
Student responses to Likert-scale statements about science and environmental sustainability awareness are presented in Table 3. Most students had a high awareness and personal connection to local science and sustainability issues before the intervention. For example, the proportion of students who had positive (strongly agree or agree) responses to these statements ranged from 65% to 80%. The prevalence of positive responses was higher after the intervention; however, these increases were only significant for the “Science is important in my daily life” statement (Table 3).

3.2. Health-Related Quality of Life

Table 4 presents the overall and domain-specific health-related quality of life scores at pre-intervention and post-intervention. Physical activity scores at pre-intervention were not statistically different from physical activity scores at post-intervention. Mean and median scores at pre-intervention and post-intervention were also not statistically different for the emotional functioning, school functioning, and social functioning domains (all p > 0.10). However, the family support scores at post-intervention were significantly higher than family support scores at pre-intervention (p < 0.001). For the Overall HRQoL score, both the mean and median score was significantly higher at post-intervention than at pre-intervention (p < 0.01). These results did not differ by gender, age, race, or school site.

4. Discussion

In this pilot study of urban, minority youth, we evaluated health-related quality of life before and after the implementation of an environmental sustainability education program with a nature contact component. We observed that overall health-related quality of life scores were significantly higher after participation in the program. We also observed higher post-intervention scores in the family support health-related quality of life domain. Although we observed post-intervention increases in mean scores for the physical activity, emotional functioning, school functioning, and social functioning domains, these increases were not significant.
Overall HRQoL scores increased after the environmental education intervention. A growing body of research has shown that environmental education increases nature contact as well as environmental awareness, environmental knowledge, and environmental affinity [1,2,3,4]. One study conducted on youths’ environmental orientation found that after an environmental education intervention, more than three-quarters of the youth claimed the program changed the way they felt about nature and increased their desire to go outside [4]. Furthermore, there is a substantial body of evidence supporting strong associations between nature contact, physical activity, and improved physical and mental health [17,20,27]. One prior study found that youth with easy access to park facilities were less likely to be overweight than youth without accessible park facilities [27]. Another study of 10- to 12-year-old youth found that increased time spent outdoors resulted in an increase in physical activity and a decrease in the prevalence of overweight youth [17]. Additional studies have observed associations between increased nature contact and improved mental health for youth [14,15,16].
In our study, we found that family support scores increased after the environmental education intervention. The mentorship and interactive learning components of the intervention may have exceptionally engaged the students, leading them to share what they learned with their family. The nature-based experiences of youth are often facilitated by or involve an adult’s presence [23]. It is possible that students’ positive experiences during the program may have encouraged family members to replicate some of the nature-based activities with them, thus increasing family support. We were unable to evaluate whether these factors were associated with the improvement in family support scores because we did not collect data on family-based activities. Future evaluations will incorporate data collection on family dynamics and collective behaviors to provide insight regarding the relationships between these factors and family support.
Our study is not without limitations. First, because this was a pilot study, the sample size was small and subject to Type II error (failing to detect a difference when one exists). Although we did not observe significant changes in four of the five HRQoL subscales, our study may have been underpowered to detect significant differences. Second, due to students moving and changing schools, approximately 13 percent of the study population was lost to follow up during the 13-week study period. Our study population comprised urban public-school students from St. Louis, Missouri, and study results may not be representative of students in other communities. Lastly, a limitation of the pre-test, post-test design is that it is possible that youth experiences over time could have confounded the results of this study. Participants may have reported better quality of life outcomes because they grew older and experienced physical, cognitive, and emotional development. We did not include a control group in this pilot study, nor did we collect information on potential events or stressors that may have influenced students’ responses to HRQoL survey items.
As this study is a first step in promoting equity in environmental education, nature contact, and health-related quality of life, future research should include a larger, more geographically diverse sample of youth. Additionally, a control group of students who did not participate in the environmental education program would allow for evaluation of the extent to which environmental education and nature contact influences youth quality of life. Our future work will build on these results by evaluating outcomes across three or more time points throughout the academic school year and including more detailed measures of family-based activities. Further, qualitative studies of the youth participants, the university student mentors, school teachers, and parents will allow us to assess multiple perspectives.

5. Conclusions

Results of our pilot study demonstrate that minority youth who participated in an environmental education and nature contact program reported improved levels of overall health-related quality of life and family support. Access to the natural environment through classroom and field-based environmental education may promote health-related quality of life. Larger, prospective studies are planned to investigate initial findings further.

Author Contributions

Conceptualization, C.C.E.; Methodology, C.C.E. and N.S.; Software, C.C.E. and D.M.S.; Formal Analysis, C.C.E. and D.M.S.; Resources, C.C.E. and N.S.; Data Curation, C.C.E. and N.S.; Writing—Original Draft Preparation, C.C.E., N.S., and D.M.S.; Writing—Review and Editing, C.C.E., N.S., and D.M.S.; Visualization, C.C.E. and D.M.S.; Supervision, C.C.E.

Funding

This work was supported in part by the Arlene Rubin Stiffman Junior Faculty Research Award from the Brown School at Washington University in St. Louis.

Acknowledgments

We would like to thank the SLPS schools, teachers, and students who participated in this study.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Wray-Lake, L.; Flanagan, C.A.; Osgood, D.W. Examining trends in adolescent environmental attitudes, beliefs, and behaviors across three decades. Environ. Behav. 2010, 42, 61–85. [Google Scholar] [CrossRef] [PubMed]
  2. Louv, R. Last Child in the Woods, Last Child in the Woods; Algonquin Books: New York, NY, USA, 2008. [Google Scholar]
  3. Larson, L.R.; Castleberry, S.B.; Green, G.T. Effects of an environmental education program on the environmental orientations of children from different gender, age, and ethnic groups. J. Park Recreat. Adm. 2010, 28, 95–113. [Google Scholar]
  4. Jennings, V.; Gaither, C.J. Approaching environmental health disparities and green spaces: An ecosystem services perspective. Int. J. Environ. Res. Public Health 2015, 12, 1952–1968. [Google Scholar] [CrossRef] [PubMed]
  5. Schwarz, K.; Fragkias, M.; Boone, C.G.; Zhou, W.; McHale, M.; Grove, J.M.; O’Neil-Dunne, J.; McFadden, J.P.; Buckley, G.L.; Childers, D.; et al. Trees grow on money: Urban tree canopy cover and environmental justice. PLoS ONE 2015, 10, e0122051. [Google Scholar] [CrossRef] [PubMed]
  6. Vaughan, K.B.; Kaczynski, A.T.; Stanis, S.A.W.; Besenyi, G.M.; Bergstrom, R.; Heinrich, K.M. Exploring the distribution of park availability, features, and quality across Kansas City, Missouri by income and race/ethnicity: An environmental justice investigation. Ann. Behav. Med. 2013, 45, S28–S38. [Google Scholar] [CrossRef] [PubMed]
  7. Dahmann, N.; Wolch, J.; Joassart-Marcelli, P.; Reynolds, K.; Jerrett, M. The active city? Disparities in provision of urban public recreation resources. Health Place 2010, 16, 431–445. [Google Scholar] [CrossRef] [PubMed]
  8. Frumkin, H.; Bratman, G.N.; Breslow, S.J.; Cochran, B.; Kahn, P.H.; Lawler, J.J.; Levin, P.S.; Tandon, P.S.; Varanasi, U.; Wolf, K.L.; et al. Nature contact and human health: A research agenda. Environ. Health Perspect. 2017, 125. [Google Scholar] [CrossRef]
  9. Bocarro, J.; Greenwood, P.B.; Henderson, K.A. An Integrative Review of Youth Development Research in Selected United States Recreation Journals. J. Park Recreat. Admi. 2008, 26, 4–27. [Google Scholar]
  10. Bogner, F.X. The Influence of Short-Term Outdoor Ecology Education on Long-Term Variables of Environmental Perspective. J. Environ. Educ. 1998, 29, 17–29. [Google Scholar] [CrossRef]
  11. McCurdy, L.E.; Winterbottom, K.E.; Mehta, S.S.; Roberts, J.R. Using nature and outdoor activity to improve children’s health. Curr. Probl. Pediatr. Adolesc. Health Care 2010, 40, 102–117. [Google Scholar] [CrossRef]
  12. Mitchell, R.; Popham, F. Effect of exposure to natural environment on health inequalities: An observational population study. Lancet 2008, 372, 1655–1660. [Google Scholar] [CrossRef]
  13. Kaplan, S. The restorative benefits of nature: Toward an integrative framework. J. Environ. Psychol. 1995, 15, 169–182. [Google Scholar] [CrossRef]
  14. Maas, J.; Verheij, R.A.; De Vries, S.; Spreeuwenberg, P.; Schellevis, F.G.; Groenewegen, P.P. Morbidity is related to a green living environment. J. Epidemiol. Community Health 2009, 63, 967–973. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  15. Wells, N.M.; Evans, G.W. Nearby nature: A buffer of life stress among rural children. Environ. Behav. 2003, 35, 311–330. [Google Scholar] [CrossRef]
  16. Cleland, V.; Crawford, D.; Baur, L.A.; Hume, C.; Timperio, A.; Salmon, J. A prospective examination of children’s time spent outdoors, purposely measured physical activity and overweight. Int. J. Obes. 2008, 32, 1685–1693. [Google Scholar] [CrossRef] [PubMed]
  17. Freeman, H. Mental health and the environment. Br. J. Psychiatry 1978, 9, 303–306. [Google Scholar] [CrossRef]
  18. Pretty, J.; Peacock, J.; Sellens, M.; Griffin, M. The mental and physical health outcomes of green exercise. Int. J. Environ. Health Res. 2005, 15, 319–337. [Google Scholar] [CrossRef] [PubMed]
  19. Glanz, K.; Rimer, B.K.; Viswanath, K. Health Behaviour and Health Education, Health Education; Wiley: Hoboken, NJ, USA, 2008. [Google Scholar]
  20. Oreskovic, N.M.; Kuhlthau, K.A.; Romm, D.; Perrin, J.M. Built Environment and Weight Disparities Among Children in High- and Low-Income Towns. Acad. Pediatr. 2009, 9, 315–321. [Google Scholar] [CrossRef] [PubMed]
  21. Russell, R.; Guerry, A.D.; Balvanera, P.; Gould, R.K.; Basurto, X.; Chan, K.M.; Klain, S.; Levine, J.; Tam, J. Humans and nature: How knowing and experiencing nature affect well-being. Annu. Rev. Environ. Resour. 2013, 38, 473–502. [Google Scholar] [CrossRef]
  22. Asah, S.T.; Bengston, D.N.; Westphal, L.M.; Gowan, C.H. Mechanisms of children’s exposure to nature: Predicting adulthood environmental citizenship and commitment to nature-based activities. Environ. Behav. 2018, 50, 807–836. [Google Scholar] [CrossRef]
  23. Stevenson, K.T.; Peterson, M.N.; Bondell, H.D.; Mertig, A.G.; Moore, S.E. Environmental, Institutional, and Demographic Predictors of Environmental Literacy among Middle School Children. PLoS ONE 2013, 8, e59519. [Google Scholar] [CrossRef] [PubMed]
  24. Nelson, E.; Wasson, J.; Kirk, J.; Keller, A.; Clark, D.; Dietrich, A.; Stewart, A.; Zubkoff, M. Assessment of function in routine clinical practice: Description of the coop chart method and preliminary findings. J. Chronic Dis. 1987, 40, 55S–63S. [Google Scholar] [CrossRef]
  25. Nelson, E.C.; Landgraf, J.M.; Hays, R.D.; Wasson, J.H.; Kirk, J.W. The functional status of patients: How can it be measured in physicians’ offices? Med. Care 1990, 28, 1111–1126. [Google Scholar] [CrossRef] [PubMed]
  26. Wasson, J.H.; Kairys, S.W.; Nelson, E.C.; Kalishman, N.; Baribeau, P. A short survey for assessing health and social problems of adolescents. Dartmouth Primary Care Cooperative Information Project (The COOP). J. Fam. Pract. 1994, 38, 489–495. [Google Scholar] [PubMed]
  27. Potwarka, L.R.; Kaczynski, A.T.; Flack, A.L. Places to play: Association of park space and facilities with healthy weight status among children. J. Community Health 2008, 33, 344–350. [Google Scholar] [CrossRef] [PubMed]
Figure 1. Environmental experiences prior to the education intervention (n = 53).
Figure 1. Environmental experiences prior to the education intervention (n = 53).
Sustainability 11 03544 g001
Table 1. Program topics and activities.
Table 1. Program topics and activities.
Fall Semester 2017Spring Semester 2018
WeekWeekly Curriculum Topics
1Introductions & tent set upFall Topics Review
2Leave No Trace PrincipalsIntroduction to Climatology
3Reduce, Reuse, RecycleWinter & Hibernation
4Introduction to PollutionIntroduction to Climate Change
5Pollution Review & Trash CleanupSpring Weather & Plants
6Habitats and EcosystemsBirds & Migration
7Food WebPollination & Seeds
8Water cycleAgriculture & Affects
9Rivers & GeomorphologyClimate Change Review & Non/Renewable Energy
10Geomorphology & GeologyEnvironmental Current Events
11Earth HistoryYour Environmental Impact
12CartographyYear Topic Review
13Fall review and conclusionGraduation
MonthMonthly nature-based activities
1Canoe TripScience Museum
2Cave Tour & Riverside HikeBird Sanctuary & Hike in Local State Park
3Overnight Camping TripUrban Farm Tour
4Indoor Rock ClimbingOvernight Camping Trip
Table 2. Characteristics of the study population (n = 53).
Table 2. Characteristics of the study population (n = 53).
Characteristicn%
Race/Ethnicity
African American4788.7
Hispanic47.5
White23.8
Gender
Female3261.5
Male2138.5
Age (years)
101018.9
112649.0
121426.4
1311.9
1423.8
Completed post-intervention questionnaire4686.8
Table 3. Science and environmental sustainability awareness at pre- and post-intervention (n=46).
Table 3. Science and environmental sustainability awareness at pre- and post-intervention (n=46).
Pre-InterventionPost-Intervention
StatementStrongly Agree/Agree (%)Mean a (SD)Strongly Agree/Agree (%)Mean a (SD)p-Value b
Scientists are active in the community.67.43.9 (1.2)84.84.0 (0.9)0.67
Scientists are trying to solve problems that are important to me.65.23.8 (1.3)84.84.1 (0.8)0.18
Science is important in my daily life.67.43.5 (1.2)84.84.0 (0.9)0.03
Sustainability is important in my daily life.71.73.9 (1.3)93.54.2 (0.6)0.27
Science is important for the problems in our world80.44.0 (1.1)904.1 (0.9)0.46
a Responses based on 5-point Likert scale (1 = strongly disagree, 5 = strongly agree. b p-values were derived from the Wilcoxon signed-rank test. Bold type indicates statistical significance at p < 0.05.
Table 4. Health-related quality of life scores at pre- and post-intervention (n = 46).
Table 4. Health-related quality of life scores at pre- and post-intervention (n = 46).
Pre-InterventionPost-Intervention
DomainMean (SD)MedianMean (SD)Medianp-Value *
Physical Activity73.6 (35.2)100.074.4 (31.0)75.00.83
Emotional Functioning63.2 (32.7)75.069.0 (31.2)75.00.36
School Functioning72.2 (26.7)75.078.2 (28.7)75.00.10
Social Functioning58.0 (32.1)75.065.8 (35.5)75.00.18
Family Support24.5 (30.4)50.053.2 (37.9)75.0<0.001
Total Overall Score292.5 (77.8)300.0340.7 (81.8)350.0<0.01
* p-values were derived from the Wilcoxon signed-rank test. Bold type indicates statistical significance at p < 0.05.

Share and Cite

MDPI and ACS Style

Ekenga, C.C.; Sprague, N.; Shobiye, D.M. Promoting Health-related Quality of Life in Minority Youth through Environmental Education and Nature Contact. Sustainability 2019, 11, 3544. https://doi.org/10.3390/su11133544

AMA Style

Ekenga CC, Sprague N, Shobiye DM. Promoting Health-related Quality of Life in Minority Youth through Environmental Education and Nature Contact. Sustainability. 2019; 11(13):3544. https://doi.org/10.3390/su11133544

Chicago/Turabian Style

Ekenga, Christine C., Nadav Sprague, and Damilola M. Shobiye. 2019. "Promoting Health-related Quality of Life in Minority Youth through Environmental Education and Nature Contact" Sustainability 11, no. 13: 3544. https://doi.org/10.3390/su11133544

APA Style

Ekenga, C. C., Sprague, N., & Shobiye, D. M. (2019). Promoting Health-related Quality of Life in Minority Youth through Environmental Education and Nature Contact. Sustainability, 11(13), 3544. https://doi.org/10.3390/su11133544

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop