Appropriateness and Utility of a Clinical Decision Support System at the Digital Front Door

Background: Digital front doors that combine symptom assessment and self-triage are increasingly used to guide patients to appropriate care, yet real-world evidence on safety, performance, and workflow impact remains limited and heterogeneous. This study reports a post-market clinical follow-up (PMCF) evaluation of a clinical decision support system (CDSS), integrated into routine care within Portugal’s largest private healthcare network (CUF) to determine whether it can deliver appropriate urgency advice and clinically useful reports, and whether its use is associated with improved preparedness and consultation efficiency in real-world practice. Methods: This was a prospective, observational study. Adults aged ≥ 18 years completed a full symptom assessment via the myCUF application before consultation. Participants provided informed consent and completed a post-assessment survey; treating physicians completed structured post-consultation surveys. Primary endpoints were the appropriateness of urgency advice and of the assessment report, including the reasonableness of suggested conditions, completeness of symptom history, concordance of the main problem with the consultation focus, and inclusion of the physician’s final diagnosis. Secondary endpoints included consultation efficiency and time saving, clinician preparedness, confidence in diagnosis, and perceived usefulness of the assessment report information. Analyses used descriptive statistics, confidence intervals, risk differences and risk ratios, with subgroup comparisons by specialty, sex, and age. Results: A total of 1,470 participants completed the post-assessment survey. Physicians returned 163 consultation surveys, of which 60 were based on reports reviewed before the encounter and formed the basis for efficiency and preparedness analyses. Urgency advice was judged appropriate in most cases (top advice level: 74.1%, 120/161; 95% CI 67.4–80.1; all advice levels: 77.6%, 125/161; 95% CI 70.1–83.9), with no significant differences by specialty, sex, or age. In cases where advice was not considered appropriate (8.7%; 95% CI 5.0–13.9), all disagreements reflected conservative, over-cautious advice; no instances of under-triage were identified. Report appropriateness was high: conditions provided as suggestions were judged reasonable in 73.0% (119/163; 95% CI 65.7–79.5), the symptom list was considered complete in 78.4% (127/162; 95% CI 71.2–84.4), the main problem discussed in the consultation matched the information in the report in 82.8% (135/163; 95% CI 76.1–88.2), and the clinician’s most likely diagnosis was included among the suggested conditions in 80.4% (131/163; 95% CI 73.5–86.0). Physicians reported efficiency improvements in 66.7% (40/60; 95% CI 53.3–78.3) and time savings in 66.1% (39/59; 95% CI 52.3–77.6), most often during the consultation itself. Increased preparedness for the consultation was reported in 71.7% (43/60; 95% CI 58.6–82.5) and was strongly associated with the perceived usefulness of the condition suggestions. Among participants, 80.5% (1,183/1,470; 95% CI 78.4–82.5) reported that all symptoms were captured in the assessment report, 71.2% (1,046/1,470; 95% CI 68.7–73.6) felt more prepared for the consultation, and 33.0% (485/1,470; 95% CI 30.5–35.6) reported reduced anxiety after assessment completion. Completeness and preparedness were associated with lower anxiety. Conclusion: In routine practice, an integrated symptom assessment device provided appropriate urgency advice and clinically useful reports, and was associated with greater clinician preparedness, perceived efficiency improvements, and positive patient experience. These PMCF findings support continued safe use as a digital front door and contribute real-world evidence for ongoing conformity assessment of Ada, a clinical decision support system and a Class IIa medical device under EU MDR 2017/745.