The perceived challenge of everyday technologies in Sweden, the United States and England: Exploring differential item functioning in the everyday technology use questionnaire

Background: The changing technological environment is reflected in regular updates made to the everyday technology (ET) use questionnaire (ETUQ). Newly added ETs may not present comparable challenges across countries and diagnoses. Aims: To identify whether country context, or dementia diagnosis, impact ETs' challenge level. Material and methods: 315 older adults from three countries were included; Sweden (n = 73), United States (n = 114), England (n = 128), and had a confirmed diagnosis of mild dementia (n = 99) or no known cognitive impairment (n = 216). Differential Items Functioning (DIF) analysis was performed on 88 ETs included in the ETUQ by country and diagnosis. The impact of DIF was evaluated in a Differential Test Functioning (DTF) analysis. Results: Nine items (10.2%) in the ETUQ showed statistically significant DIF between countries; five of which were public space ETs and none of which were information and communication technologies (ICTs). Three ICT items, and no others, showed significant DIF by diagnosis. The items' DIF was shown to have no impact upon person measures of ability to use ET in the DTF.