**5. Conclusions**

This study aimed to investigate the factors determining the sustainable consumption behaviour of consumers in Bulgaria. To address this issue, a conceptual model was created to provide a thorough understanding of the study. The model involved possible connections between environmental knowledge, materialism, environmental influences, the promotion of sustainable consumption, and sustainable consumption behavioural intention, which may influence and lead to SCB. Moreover, it was assumed that age played a moderating role in associations of influencing factors with SCB. The literature review revealed that these links had not been extensively studied; however, they could be important in a deeper study of the SCB. In this sense, this study contributes to the literature on sustainable consumption behaviour by investigating a few relatively new linkages, i.e., the effect of MAT and PSC on SCB. Furthermore, the mediating effect of SCBI in such a conceptual framework has not been examined yet.

Some limitations of this study should be noted. Firstly, our research is limited geographically to the population of one European country, i.e., Bulgaria; the results might differ if other cultural contexts are considered. Secondly, the respondents were approached through a non-probability-based sampling method, which has issues of respondent selection bias and may therefore restrict again the generalisability of the findings.

The current study enriches the literature on sustainable consumption behaviour by explaining the links between insufficiently studied internal and external factors influencing SCB. Future research should attempt to expand the range of the factors that may be considered SCB determining factors. The design of our study excluded detailing the context. It would be useful to carry out research on factors significant for SCB in specific areas of occurrence, such as the food sector, the fast fashion industry, the hospitality industry, etc. Our conceptual framework emphasised the moderating role of age. Future studies could also test the moderating effect of other demographic variables, such as gender, income, education level, residence, etc., on the relationships between SCB and its antecedents. Moreover, this study used a quantitative approach to test the study hypotheses, whereas it may be recommended that future studies use mixed methods to gain an in-depth understanding of the SCB phenomenon.

**Author Contributions:** Conceptualisation, T.D. and I.I.; introduction, M.A.; literature review, T.D.; methodology, T.D.; software, I.I.; validation, T.D. and I.I.; formal analysis, I.I.; investigation, T.D.; resources, M.A.; data curation, I.I.; writing—original draft preparation, T.D., I.I. and M.A.; writing review and editing, M.A.; visualisation, T.D. and I.I.; supervision, M.A.; project administration, T.D.; funding acquisition, T.D. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by Project № ΦΠ21-ΦИCH-004; financing organization: Fund "Scientific Research" at the University of Plovdiv Paisii Hilendarski.

**Institutional Review Board Statement:** The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee of the certified sociological agency BluePoint Ltd. The respondents confirmed their participation using a Consent Form.

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Data Availability Statement:** The data presented in this study are available on request from the corresponding author.

**Conflicts of Interest:** The authors declare no conflict of interest.

## **Appendix A**


**Table A1.** Previous studies examining the influencing factors of sustainable consumption behaviour.


#### **Table A1.** *Cont.*


#### **Table A1.** *Cont.*

## **Appendix B**

**Table A2.** Measurement items for the constructs in the research model.


**Table A2.** *Cont.*

**Constructs and Items Sources**

Care for the future generation

CFG 1. I always remember that my excess consumption can create hindrances for the future generation to meet

their basic needs.

CFG 2. I care for the need fulfilment of the next generation.

CFG 3. I often think about future generations' quality of life.

CFG 4. I try to control my desire for excessive purchases for the sake of future generations.

CFG 5. I am concerned about future generations.

CFG 6. I try to minimise excess consumption for the sake of preserving environmental resources for

future generations.

#### **References**


Fink, Arlene G. 2016. *How to Conduct Surveys: A Step-by-Step Guide*. Thousand Oaks: SAGE Publications.


Pimdee, Paitoon. 2020. Antecedents of Thai student teacher sustainable consumption behavior. *Heliyon* 6: e04676. [CrossRef]

