Development and validation of a questionnaire for assessing the determinants that predict household recycling (ReDom Questionnaire).

The growing tendency towards 'urbanization' is promoting an increase in resource consumption and waste generation, which requires proper waste separation management with active participation of the population. To this end, it is essential to know the personal modifiable factors that predict recycling. The primary aim of the present study is to develop and evaluate the psychometric properties of a Spanish language questionnaire designed to measure determinants of household waste separation for recycling purposes (ReDom Questionnaire). A cross-cultural adaptation, translation and psychometric evaluation was undertaken of an extant questionnaire originally developed in Swedish, and the resultant Spanish questionnaire was then subjected to reliability and validity testing. The questionnaire was developed using survey data from 759 respondents and 33 participants performed the retest to assess reliability. The resultant 'ReDom Questionnaire' is composed of three factors that draw on relevant elements of the COM-B framework: motivation (seven items), physical opportunity (three items) and social opportunity (three items). The accuracy of the scores is adequate both in terms of internal consistency (factorial weights >0.60; comparative fit index = 0.994; root mean square error of approximation = 0.049; root mean square residual (RMSR) = 0.053) and reliability (Pearson correlation >0.65; Cronbach's alpha >0.75). In conclusion, the Spanish ReDom Questionnaire showed adequate psychometric properties and appears useful for assessing the determinants of household waste separation.