CClinicalTrials.gg
CompletedNCT06004531PALUpdated Sep 11, 2026

Planetary Health and Loneliness

An interventional study of Regulation Of Craving Training (ROC-T) and Control group in Loneliness, Anxiety and Health-Related Behavior, sponsored by Jacobs University Bremen gGmbH. Completed at 1 site in Germany. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-11.

Sponsored by Jacobs University Bremen gGmbH · Not applicable, Interventional, and Prevention

Phase
Not applicable
Study type
Interventional
Enrollment
1,684
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

The aim of this 3-phase study is the evaluation of planetary health behaviors and its cognitive processes in relation to levels of eco-anxiety, general well-being, and levels of loneliness. As climate change progresses at a dangerous rate, it is important to establish and maintain lifestyles that are productive, fulfilling, environmentally conscious, and low in anxiety. Through a better understanding of the interconnected nature of planetary health behaviors with other aspects of healthy living and perception of social isolation, and the effect of an intervention, this research will add to current state of science to help inform the creation of interventions promoting sustainable, healthy, happy living among the general public and specific subgroups.

Read the detailed description

The aim of this study with three phases is the evaluation of healthy behaviors and its cognitive processes, and anxiety levels in relation to selected physical, mental, and environmental health aspects by means of online survey in (1) general population and (2) rehabiliation setting as well as with (3) an experimental design with students/ see section "Arms and Interventions".

The umbrella terminology of "planetary health" is used in the context of this study. As climate change progresses at a dangerous rate, it is important to establish and maintain lifestyles that are productive, fulfilling, environmentally conscious, and low in anxiety and stress. By evaluating prevalence of healthy behaviors and levels of eco-anxiety as well as loneliness as one early indicator of health risk, this study hopes to build on existing public health knowledge to develop interventions targeting and encouraging multiple aspects of healthy, eco-friendly lifestyles. This study will also help later intervention design by determining effective methods of persuasion and promotion of sustainable planetary health behaviors.

Main research questions are

*Phase 1/general population*

I. Is climate-awareness (in terms of EMCB, YCSCB and Mindful Health) more likely to also increase motivation to promote own health (in terms of physical activity and healthy nutrition)?

*Phase 1/general population*

II. What is the (non-)linear relationship between eco-anxiety and climate-sensitiveness/health behavior?

*Phase 1/general population and Phase 2/rehabiliation setting*

III. Is climate-sensitiveness and eco-anxiety invariant to socio-demographic variables such as clinic, gender, occupation, and age? (No differences)

*Phase 2/rehabiliation setting*

IV. To what extent are pattern in medical rehabilitation different from the general population?

*Phase 3/students and experiment-based*

VI. Does priming eco-anxiety lead individuals to process eco-health-related decisions more deliberately and to make more decisions beneficial to eco-health?

*Phase 3/students and experiment-based*

VII. Is an intervention leading individuals to make more behavioral decisions beneficial to personal and ecological health?

*Phase 3/students and experiment-based*

VIII. Does environmental anxiety induction interact with ROC-T intervention? How does ecological anxiety initiation or intervention effect manifest through changes in the parameters of the drift-diffusion model to reflect changes in the decision-making process?

*Phase 3/students and experiment-based*

IX. Do the observed effects on personal health decisions extend (transfer) to the ecological choice domain?

02

Conditions studied

  • Loneliness
  • Anxiety
  • Health-Related Behavior
  • Healthy Lifestyle
  • Healthy Nutrition
  • Healthy Diet
  • Health Behavior
  • Choice Behavior

Keywords

  • Planetary Health
  • Eco-Friendly Behavior
  • Eco-Anxiety
  • Covid-19
03

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Ability to participate in surveys (e.g., sufficient German or English language skills)

Exclusion criteria

Exclusion Criteria:

  • Not being of age
  • Illiteracy
  • Massively limited cognitive abilities (linguistic components of the digital offerings must be able to be used and questionnaires completed or interviews participated in)
04

Study design

Phase
Not applicable
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Single (Participant)
Enrollment
1,684 participants (actual)

Study arms

  • Experimental
    Eco-anxiety priming

    Participants viewed a 2-minute climate change video presenting environmental threats to human survival.

    Behavioral: Regulation Of Craving Training (ROC-T) · Behavioral: Control group

  • Experimental
    Control Arm

    Participants viewed a 2-minute neutral nature documentary without climate change content.

    Behavioral: Regulation Of Craving Training (ROC-T) · Behavioral: Control group

Interventions

  • BehavioralRegulation Of Craving Training (ROC-T)

    Participants read a 5-minute article on food and ecological health describing the environmental impacts of food choices and actions to support planetary health. During a subsequent choice task, participants received prompts to recall article content and self-monitor their selections.

  • BehavioralControl group

    Control participants read a time-matched article unrelated to sustainability (no multi-domain pro-environmental behaviors including transportation, consumption, and daily activities; just on the beauty of the German nature) and completed the choice task without recall prompts.

05

What researchers measure

Primary outcomes

  1. Young Consumers' Sustainable Consumption Behaviors (YCSCB) validated scale

    The primary outcome measure will be the YCSCB validated scale questionnaire. This will be given to participants right after they have completed the intervention section of the survey. The answering options range from "Never" (0, minimum score) to "Sometimes" (1) and "Often" (2) up to "Always" (3, maximum score). The items are worded 1. I eat meat (steak, ham, etc.). 2. I eat dairy products (butter, cheese, yoghurt, etc.). 3. I keep a healthy diet. 4. There are times when I discard food products. 5. I buy locally grown food products. 6. I reuse my leftovers for the next meal. and items # 1, 2 and 4 need to be reversed, then all items can be used as single items or as aggregated scales, with higher scores indicating a better outcome in terms of planetary health.

    Time frame: This scale will take approximately 2 minutes to fill out completely.

  2. Ethically Minded Consumer Behavior (EMCB) validated scale

    The second primary outcome measure will be the EMCB validated scale questionnaire. This will be given to participants right after they have completed the intervention section of the survey. The answering options range from "Never true" (0, minimum score) to "Rarely true" (1), "Sometimes true" (2), "Mostly true" (3) and "Always true" (4, maximum score). The items are worded (for instance) 1. When there is a choice, I always choose the product that contributes to the least amount of environmental damage. 2\. I have switched products for environmental reasons. 3. If I understand the potential damage to the environment that some products can cause, I do not purchase those products. ... 10. I have paid more for socially responsible products when there is a cheaper alternative. All items can be used as single items or as aggregated scales, with higher scores indicating a better outcome in terms of planetary health.

    Time frame: This scale will take approximately 2 minutes to fill out completely.

  3. Loneliness item from the Center for Epidemiological Studies-Depression-(CES D)-Scale

    To study some of the research questions unrelated to the intervention, the perceived social isolation is measured with a standardized scale building on the item in the Center for Epidemiological Studies-Depression-(CES-D)-Scale. The item is worded "How often did you feel lonely?" with the answering options "Daily" (3), "Several times a week" (2), "Once a week" (1) and "Rarely/never" (0). The item can be used as single items, with higher scores indicating a worse outcome in terms of more loneliness.

    Time frame: This item will take less than 1 minute to complete.

06

Study locations

1 site
  • Germany
    Bremen, 28759, Germany
07

References and documents

Publications

  • Arias, P., Bellouin, N., Coppola, E., Jones, C., Krinner, G., Marotzke, J., Naik, V., Plattner, G.-K., Rojas, M., Sillmann, J., Storelvmo, T., Thorne, P., Trewin, B., Achutarao, K., Adhikary, B., Armour, K., Bala, G., Barimalala, R., Berger, S., & Zickfeld, K. (2021, January). Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change; Technical Summary.
  • Bull ER, McCleary N, Li X, Dombrowski SU, Dusseldorp E, Johnston M. Interventions to Promote Healthy Eating, Physical Activity and Smoking in Low-Income Groups: a Systematic Review with Meta-Analysis of Behavior Change Techniques and Delivery/Context. Int J Behav Med. 2018 Dec;25(6):605-616. doi: 10.1007/s12529-018-9734-z. PubMed 30003476 ↗
  • Cheng J, Xu Z, Bambrick H, Prescott V, Wang N, Zhang Y, Su H, Tong S, Hu W. Cardiorespiratory effects of heatwaves: A systematic review and meta-analysis of global epidemiological evidence. Environ Res. 2019 Oct;177:108610. doi: 10.1016/j.envres.2019.108610. Epub 2019 Jul 26. PubMed 31376629 ↗
  • Dohle S, Hofmann W. Consistency and Balancing in Everyday Health Behaviour: An Ecological Momentary Assessment Approach. Appl Psychol Health Well Being. 2019 Mar;11(1):148-169. doi: 10.1111/aphw.12148. Epub 2018 Nov 13. PubMed 30426704 ↗
  • Druckman, A., & Jackson, T. (2016). Understanding Households as Drivers of Carbon Emissions. In R. Clift & A. Druckman (Eds.), Taking Stock of Industrial Ecology (pp. 181-203). Springer International Publishing. https://doi.org/10.1007/978-3-319-20571-7_9
  • Ford ES, Bergmann MM, Boeing H, Li C, Capewell S. Healthy lifestyle behaviors and all-cause mortality among adults in the United States. Prev Med. 2012 Jul;55(1):23-7. doi: 10.1016/j.ypmed.2012.04.016. Epub 2012 Apr 29. PubMed 22564893 ↗
  • Geller K, Lippke S, Nigg CR. Future directions of multiple behavior change research. J Behav Med. 2017 Feb;40(1):194-202. doi: 10.1007/s10865-016-9809-8. Epub 2016 Oct 26. PubMed 27785652 ↗
  • Lacroix, K. (2018). Comparing the relative mitigation potential of individual pro-environmental behaviors. Journal of Cleaner Production, 195, 1398-1407. https://doi.org/10.1016/j.jclepro.2018.05.068
  • Lange, F., & Dewitte, S. (2019). Measuring pro-environmental behavior: Review and recommendations. Journal of Environmental Psychology, 63, 92-100. https://doi.org/10.1016/j.jenvp.2019.04.009
  • Loef M, Walach H. The combined effects of healthy lifestyle behaviors on all cause mortality: a systematic review and meta-analysis. Prev Med. 2012 Sep;55(3):163-70. doi: 10.1016/j.ypmed.2012.06.017. Epub 2012 Jun 24. PubMed 22735042 ↗
  • Mauch CE, Edney SM, Viana JNM, Gondalia S, Sellak H, Boud SJ, Nixon DD, Ryan JC. Precision health in behaviour change interventions: A scoping review. Prev Med. 2022 Oct;163:107192. doi: 10.1016/j.ypmed.2022.107192. Epub 2022 Aug 11. PubMed 35963310 ↗
  • Meader N, King K, Wright K, Graham HM, Petticrew M, Power C, White M, Sowden AJ. Multiple Risk Behavior Interventions: Meta-analyses of RCTs. Am J Prev Med. 2017 Jul;53(1):e19-e30. doi: 10.1016/j.amepre.2017.01.032. Epub 2017 Feb 28. PubMed 28258777 ↗
  • Moran, D., Wood, R., Hertwich, E., Mattson, K., Rodriguez, J. F. D., Schanes, K., & Barrett, J. (2020). Quantifying the potential for consumer-oriented policy to reduce European and foreign carbon emissions. Climate Policy, 20(sup1), S28-S38.
  • Nisa CF, Belanger JJ, Schumpe BM, Faller DG. Meta-analysis of randomised controlled trials testing behavioural interventions to promote household action on climate change. Nat Commun. 2019 Oct 4;10(1):4545. doi: 10.1038/s41467-019-12457-2. PubMed 31586060 ↗
  • Nisbet, E. K. L., & Gick, M. L. (2008). Can health psychology help the planet? Applying theory and models of health behaviour to environmental actions. Canadian Psychology / Psychologie Canadienne, 49(4), 296-303.
  • Osbaldiston, R., & Schott, J. P. (2012). Environmental Sustainability and Behavioral Science: Meta-Analysis of Proenvironmental Behavior Experiments. Environment and Behavior, 44(2), 257-299.
  • Prochaska JJ, Spring B, Nigg CR. Multiple health behavior change research: an introduction and overview. Prev Med. 2008 Mar;46(3):181-8. doi: 10.1016/j.ypmed.2008.02.001. Epub 2008 Feb 6. PubMed 18319098 ↗
  • Riediger M, Freund AM. Interference and facilitation among personal goals: differential associations with subjective well-being and persistent goal pursuit. Pers Soc Psychol Bull. 2004 Dec;30(12):1511-23. doi: 10.1177/0146167204271184. PubMed 15536236 ↗
  • Santos, O., Virgolino, A., Vaz Carneiro, A., & De Matos, M. G. (2021). Health Behavior and Planetary Health: A Multi-Level Environmental Health Approach. European Psychologist, 26(3), 212-218.
  • Steg, L., & Vlek, C. (2009). Encouraging pro-environmental behaviour: An integrative review and research agenda. Journal of Environmental Psychology, 29(3), 309-317.
  • Truelove, H. B., Carrico, A. R., Weber, E. U., Raimi, K. T., & Vandenbergh, M. P. (2014). Positive and negative spillover of pro-environmental behavior: An integrative review and theoretical framework. Global Environmental Change, 29, 127-138.
  • United Nations Development Programme. (2022). United Nations (UN).
  • World Health Organization. COP26 special report on climate change and health: The health argument for climate action. Report No.: 9240036725. (2021). World Health Organization.
  • Wu S, Zhu W, Thompson P, Hannun YA. Evaluating intrinsic and non-intrinsic cancer risk factors. Nat Commun. 2018 Aug 28;9(1):3490. doi: 10.1038/s41467-018-05467-z. PubMed 30154431 ↗

Individual participant data

Plan to share: No — Individual participant data (IPD) will not be published. Other researchers are welcome to get in contact with the PI to get access to anonymous data.

08

Registry details

Key details

Study ID
NCT06004531
Lead sponsor
Jacobs University Bremen gGmbH
Responsible party
Sponsor
First posted
Aug 22, 2023
Start date
Dec 28, 2024
Primary completion
Dec 31, 2024
Completion
Dec 31, 2025
Last update
Sep 11, 2026

Study contacts

Sonia Lippke, Dr.
principal investigator · Constructor University

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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