EFFET - Study of Executive Functions Regarding the Usability and User Experience of Assistive Technologies Among the Elderly

Evaluate the impact of mental flexibility on the usability of a digital interface

=> correlation between the Trail Making Test Z-score and the usability score (completion time in seconds) for the digital task under low executive load conditions.

The Trail Making Test consists of two sheets (A and B). On sheet A, the participant must connect numbers in ascending order (time and number of errors are recorded). On sheet B, the participant must alternate between connecting numbers and letters (time, number of errors, and number of perseverations are recorded). A Z-score is calculated using the recorded scores.

Evaluate the impact of mental flexibility on user experience

=> correlation between the Trail Making Test Z-score and the UEQ score under conditions of low executive load.

UEQ (26 items) : a questionnaire evaluating user experience across six dimensions: attractiveness, perspicuity, efficiency, dependability, stimulation, and novelty. These dimensions can be grouped into two subscales: pragmatic (efficiency, clarity, dependability) and hedonic (stimulation and novelty). Each item is rated on a scale of 1 to 7, with results converted into composite scores. A score close to +3 indicates a very positive experience, while a score close to -3 indicates a negative experience. The score for each UEQ dimension will be recorded. The questionnaire is administered via interviewer-led assessment (taking approximately 15 minutes).

Evaluate the impact of inhibition on usability

=> correlation between the Victoria Stroop Z-score and the usability score (completion time in seconds) under low executive load conditions.

The Victoria Stroop test consists of three cards (color, word, and interference). On the color card, participants must name the color of 24 colored circles (time, corrected errors, uncorrected errors, and total errors are recorded). On the word card, they must read 24 words printed in colored ink (time, corrected errors, uncorrected errors, and total errors are recorded). On the interference card, they must name the ink color of 24 words denoting a different color (e.g., the word "red" printed in yellow ink); time, corrected errors, uncorrected errors, and total errors are recorded. A Z-score is calculated based on the recorded scores.

Evaluate the impact of inhibition on the user experience

=> correlation between the Victoria Stroop Z-score and the UEQ score under low executive load conditions.

Evaluate the impact of the update on usability

=> correlation between the 2-back d'score and the usability score (completion time in seconds) under low executive load conditions.

The 2-back task involves presenting a series of 30 letters one by one. For each letter presented, the participant must indicate-by pressing a keyboard key-whether it is identical to the letter presented two items previously. It yields five metrics: the number of correctly detected targets, false alarms, missed targets, correctly rejected targets, and the d-prime (d') score. The d' score is used as the primary metric.

Evaluate the impact of the update on the user experience

=> correlation between the 2-back d'score and the UEQ score under low executive load conditions.

Describe the participants' level of digital skills (control variable)

=> score on the MDPQ-16 questionnaire. Technological skills will be measured using the Mobile Device Proficiency Questionnaire (MDPQ-16), which assesses proficiency in using mobile devices (smartphones and tablets) among older adults. The MDPQ-16 questionnaire consists of 16 items rated on a 5-point Likert scale ranging from 1 ("Never done") to 5 ("Very easily"), with a maximum total score of 80. It is administered via interviewer assessment (taking approximately 5 minutes), and the score for each Likert scale item is recorded.

Describe the participants' level of cognitive reserve (control variable)

=> score on the CRI-q questionnaire. CRI-q questionnaire evaluates four dimensions: CRI Total, CRI Education, CRI Work, and CRI Leisure. Responses to each item will be recorded. Each dimension yields a standardized score, calculated using an Excel file provided by the authors. This questionnaire is normed for ages up to 102. It is administered via interviewer assessment (taking approximately 15 minutes).

Describe the participants' level of technology acceptance (control variable)

=> score on the STAM questionnaire. Attitudes toward technology will be measured using the S-STAM (Short-Senior Technology Acceptance Model), a 14-item questionnaire covering four dimensions: attitudes (3 items), control (4 items), anxiety (2 items), and health (5 items). Each item is rated on a Likert scale from 1 to 10. The maximum score is 140. Scores for each Likert scale are recorded. Developed for older adults, it is administered via interviewer assessment (taking approximately 10 minutes).

Compare the usability score between the low executive load interface and the high executive load interface

=> comparison of the usability score (completion time in seconds) between the two experimental conditions (low vs. high executive load).

Compare the user experience score between the low executive load interface and the high executive load interface

=> comparison of the UEQ score between the two experimental conditions (low vs. high executive load).

Compare the perceived cognitive load score between the low executive load interface and the high executive load interface

=> comparison of the perceived cognitive load score between the two experimental conditions (low vs. high executive load).