Development and psychometric properties of the Digital Difficulties Scale (DDS): An instrument to measure who is...

Today, some individuals may be at a disadvantage by experiencing difficulties in using a smartphone or computer to reach specific outcomes (e.g., looking for a job, searching for information on insurances) or in general (e.g., not knowing how to change the settings of an app or website). The aim of this study is to develop and examine the psychometric properties of a new instrument, called the Digital Difficulties Scale (DDS). A multi-phase method was performed to develop the questionnaire in the period from January 2019 to November 2019. The item pool was generated based on a literature review, informal observations and interviews. Then, this item pool was presented both to experts (n = 6) and non-experts (n = 492) to assess content and face validity. In a second stage, construct validity (both exploratory and confirmatory), convergent and divergent validity, internal consistency, and test-retest reliability of the questionnaire were tested. These analyses were based on a representative sample (n = 1000), and an independent sample for test-retest reliability (n = 44). Twenty-four items were generated and refined during content and face validity assessment. The exploratory factor analysis revealed three factors (Specific Digital Difficulties, General Digital Difficulties, and Worries about Future Digital Difficulties) containing sixteen items, together explaining 73.03% of the observed variance. The confirmatory factor analysis proved adequate model fitness. Both convergent and divergent validity were good, and internal consistency was excellent, with Cronbach's alphas ranging between .93 and .97. Finally, our instrument demonstrated good test-retest reliability, with interclass correlation coefficients between .73 and .86. Consequently, the DDS can be used both in future research and practice, as it is a valid and reliable instrument to measure who is disadvantaged to fulfill basic needs by experiencing difficulties in using a smartphone or computer.