Development of the Green Cities Questionnaire (GCQ) in Germany: Focus on Mental Health, Willingness to Pay for Sustainability, and Incentives for Green Exercise

Green cities can contribute to greater mental and physical well-being. In addition, many people enjoy being active outdoors (green exercise). As yet, no questionnaire jointly emphasises mental health, willingness to pay for sustainability, and the incentive of a green environment for physical exercise in cities. Therefore, I developed the new Green Cities Questionnaire (GCQ), comprising 18 items, and used it to survey the perceptions of 249 participants (130 female, 119 male, 0 diverse; aged 18 to 84). Then, I applied exploratory factor analyses where the three factors of mental health (MH; nine items), willingness-to-pay (WTP; five items), and green exercise (GE; four items) were extracted. Additional statistical analyses revealed that women reported higher values on the MH and GE factors than men. In particular, women and men reported a beneficial effect of green cities on mental health (higher ratings on MH than on GE and on WTP). However, there was no gender effect on WTP. From an urban-planning perspective, the two strongest implications are as follows: First, the GCQ facilitates measurement of the three key latent factors: MH, WTP, and GE. However, future validation studies with larger sample sizes and applications of the GCQ alongside additional similar and different recognised scales are necessary to establish convergent and discriminant validity. Second, mental health is reported to be much more important than WTP and GE. Hence, green initiatives, educational programs, and green city workshops should not only focus on expanding urban green spaces but also on providing appropriate relaxation areas to promote and foster psychological well-being and quality of life in green cities.