18 and older, any sex, with Diabetic Retinopathy or Macular Degeneration. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Decisional Conflict Scale (DCS) Scores at Day 0 (Post-intervention)Primary· Day 0 (Post-intervention)
Decision conflict scale (DCS) is calculated from 16 items, with each item ranging from 0 (strongly agree) to 4 (strongly disagree). The total score is reported on a 0-100 scale by summing all responses, dividing by 16 and multiplying by 25. Higher scores represent greater levels of uncertainty in decision-making (higher decision conflict = worse outcome), and interventions often aim to reduce decision conflict (lower decision conflict = greater likelihood of implementing a decision = better outcome).
Group
Value
95% CI
Older Drivers Website
15.2
± 13.3
Driving Decision Aid
12.3
± 12.9
Values Clarity Subscale Score at Day 0 (Post-intervention)Secondary· Day 0 (Post-intervention)
For the values clarity subscale, three decision conflict scale (DCS) items (Likert scale responses from 0 \['strongly agree'\] to 4 \['strongly disagree'\]) are summed, divided by 3 and multiplied by 25; scores range from 0 (extremely clear) to 100 (extremely unclear about personal values); lower scores represent higher values clarity, which is a better outcome. Lower values clarity subscale scores are associated with positive outcomes. The measure will be assessed in drivers immediately following administration of control condition or intervention.
Group
Value
95% CI
Older Drivers Website
13.8
± 15.3
Driving Decision Aid
12.8
± 15.4
Older Adult Driving Safety Knowledge Scores as Assessed by True/False Questions at Day 0 (Post-intervention)Secondary· Day 0 (Post-intervention)
The following true/false questions will be used to examine participants' safe driving knowledge: 1) Older drivers pose a bigger risk to other drivers and pedestrians than younger drivers do; 2) Drivers aged 70 years and older are more likely to be hurt or killed if they are in a crash; 3) There is a milestone age when everyone should stop driving; 4) With age, a person needs more light to see well; 5) Getting lost on familiar roads is a sign that it might be time to stop driving. A higher number of correctly answered questions indicate better outcomes. Knowledge will be defined as the percenta
Group
Value
95% CI
Older Drivers Website
79.9
± 18.4
Driving Decision Aid
88.9
± 16.4
Decision Self Efficacy Score at Day 0 (Post-intervention)Secondary· Day 0 (Post-intervention)
The Decision Self-Efficacy Scale will be used to assess decision self efficacy. Scores range from 0 (extremely low self-efficacy; worst outcome) to 100 (extremely high self-efficacy; best outcome). Higher scores indicate better outcomes. The measure will be assessed in drivers immediately following administration of control condition or intervention
Group
Value
95% CI
Older Drivers Website
92.9
± 10.3
Driving Decision Aid
93.2
± 9.4
Change in Patient-Reported Outcomes Measurement Information System (PROMIS) 4-item Depression ScoreSecondary· 6 months, 12 months, 18 months, 24 months
Depression will be measured using the PROMIS Short Form 4-item scale (4a Adult v1.0), with higher PROMIS scores indicating higher depression. PROMIS scores are presented as standardized T-scores (mean=50, standard deviation=10). Lower PROMIS depression scores indicate better outcomes (lower depression).
Change in depression is calculated as the PROMIS depression score at each time point (6, 12, 18, or 24 months) minus the score at baseline (pre-randomization). Since PROMIS scores at each time point can range from 41.0 to 79.4, change in depression PROMIS scores can range from -38.4 to +38.4.
Change in decision regret will be measured by the Ottawa Decision Regret Scale. This validated measure correlates with decision satisfaction and conflict, and overall quality of life. Scored from 0-100, high scores represent higher regret. Lower scores indicate better outcomes.
Decision regret was measured at 6, 12, 18, and 24 months, so change in decision regret can be calculated from 12 months (vs. 6 months), 18 months (vs. 6 months), and 24 months (vs 6 months). Since decision regret scores range from 0-100, change in decision regret scores range from -100 to + 100, with change-scores \<=
12 month change-score (12 month - 6 month)
Group
Value
95% CI
Older Drivers Website
3.24
± 15.61
Driving Decision Aid
-1.98
± 9.57
18 month change-score (18 month - 6 month)
Group
Value
95% CI
Older Drivers Website
2.39
± 15.55
Driving Decision Aid
-1.57
± 10.59
24 month change-score (24 month - 6 month)
Group
Value
95% CI
Older Drivers Website
1.71
± 15.13
Driving Decision Aid
0.37
± 12.47
Change in Life Space ScoreSecondary· 6 months, 12 months, 18 months, 24 months
Life space is a global measure of mobility and community engagement. The Life-Space Assessment instrument (UAB Study of Aging) is a validated tool assessing recent mobility and function. Composite scores range from 0 (bedbound) to 120 (travel out of town every day without assistance); scores of ≤60 are correlated with lower levels of social participation and higher mortality. Higher scores indicate better outcomes.
Change in life space can be calculated at 6 months (vs baseline), 12 months (vs baseline), 18 months (vs baseline), and 24 months (vs baseline). Since life space scores range from
Self-reported driving frequency will be measured by number of days per week participants drive, with consideration of higher or lower frequency as a positive or negative outcome in the context of participant's intent to drive with lower or higher frequency.
In the final study survey, this question was reworded, so participants were asked "during the past 6 months, have you reduced the number of days per week you normally drive?" with response options of "yes", "no", "I don't know". Percentage of those who answered "yes" at each time point are reported.
Driving avoidance in certain situations will be measured by asking participants about their avoidance of riskier driving situations, e.g., nighttime driving, with consideration of avoidance in certain situations as a positive or negative outcome in the context of participant's intent to avoid these situations.
Avoidance of night driving was worded as: "Using a scale from 1 to 7 where 1 is Not At All Comfortable and 7 is Completely Comfortable, how comfortable do you feel in the following situation?", and the situation presented was "Driving at night?". Higher scores indicate greater comfort w
Driving cessation will be measured by asking participants whether they are currently driving; all participants were currently driving at study baseline. Consideration of driving cessation as a positive or negative outcome will be determined in the context of participant's intent to engage in driving cessation. This question was worded as "Do you currently drive?" with response options of "yes" and "no". The numbers reported are those who said "no", which represents driving cessation.
The wording of this question was added to the study after an early DSMB meeting, so less data are available fo
Occurrence of self-reported crashes will be measured by ≥1 crash versus no crashes, where ≥1 crash is a negative outcome.
6 month
Group
Value
95% CI
Older Drivers Website
15
Driving Decision Aid
9
12 month
Group
Value
95% CI
Older Drivers Website
10
Driving Decision Aid
10
18 month
Group
Value
95% CI
Older Drivers Website
10
Driving Decision Aid
12
24 month
Group
Value
95% CI
Older Drivers Website
12
Driving Decision Aid
13
Adverse events — posted to ClinicalTrials.gov
Time frame: 2 years of study from enrollment to follow-up (baseline, 6 month, 12 month, 18 month, 24 month visits).
Reporting threshold: 0%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
This Stage II randomized, controlled, longitudinal trial seeks to assess the acceptability, feasibility, and effects of a driving decision aid use among geriatric patients and providers. This multi-site trial will (1) test the driving decision aid (DDA) in improving decision making and quality (knowledge, decision conflict, values concordance and behavior intent); and (2) determine its effects on specific subpopulations of older drivers (stratified for cognitive function, decisional capacity, and attitudinally readiness for a mobility transition). The overarching hypotheses are that the DDA will help older adults make high-quality decisions, which will mitigate the negative psychosocial impacts of driving reduction, and that optimal DDA use will target certain populations and settings.
Publications & conference data
6 peer-reviewed publications reference this trial (live from Europe PMC):
Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by University of Colorado, Denver
Last refreshed: 21 February 2025
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT04141891.