Capturing nature Connectedness: Validity and utility of the Dutch nature connection index

Nature connectedness is increasingly recognized for its role in promoting mental health and planetary health. Valid nature connectedness scales are crucial to study these relations. While several scales exist to measure this construct, there is a need for improvement in their methodological quality. This study aimed to evaluate the validity and utility of the Dutch translation of the Nature Connection Index (NCI), a scale originally developed in English by Hunt et al. (2017) and Richardson et al. (2019). Survey data from two samples of young adults aged between 18 and 35 years were used (n = 1728; n = 1608). Confirmatory Factor Analysis and Exploratory Factor Analysis were performed, and Cronbach's alfa was calculated. Pearson's correlations between the NCI and measures of nature connectedness, nature contact, climate change importance, and mental wellbeing were analyzed to evaluate concurrent validity, convergent validity, and the utility of the NCI. Utility was further assessed by testing the NCI's ability to detect socio-demographic differences using one-way ANOVA. Consistent with the original English scale, the Dutch version of the NCI loaded onto a single factor and demonstrated high internal consistency (α = 0.89). Strong correlations with another measure of nature connectedness, moderate correlations with nature contact and climate change importance, and weak correlations with mental wellbeing outcomes were found. Additionally, NCI scores differed across subgroups defined by gender, education level, relationship status, and student status. The findings suggest that the Dutch NCI is reliable and valid instrument for measuring nature connectedness in Dutch speaking populations. • The Dutch NCI showed similar psychometric properties as the original scale. • Correlations with nature contact implied its convergent validity. • Correlations with climate change importance implied its convergent validity. • Correlations with mental wellbeing outcomes implied its utility. • The Dutch NCI is a reliable, valid, and useful tool to assess nature connectedness.