Do patients who read visit notes on the patient portal have a higher rate of "loop closure" on diagnostic tests and referrals in primary care? A retrospective cohort study

Objectives: The 2021 US Cures Act may engage patients to help reduce diagnostic errors/delays. We examined the relationship between patient portal registration with/without note reading and test/referral completion in primary care.Materials and methods: Retrospective cohort study of patients with visits from January 1, 2018 to December 31, 2021, and order for (1) colonoscopy, (2) dermatology referral for concerning lesions, or (3) cardiac stress test at 2 academic primary care clinics. We examined differences in timely completion ("loop closure") of tests/referrals for (1) patients who used the portal and read >1 note (Portal + Notes); (2) those with a portal account but who did not read notes (Portal Account Only); and (3) those who did not register for the portal (No Portal). We estimated the predictive probability of loop closure in each group after adjusting for socio-demographic and clinical factors using multivariable logistic regression.Results: Among 12 849 tests/referrals, loop closure was more common among Portal+Note-readers compared to their counterparts for all tests/referrals (54.2% No Portal, 57.4% Portal Account Only, 61.6% Portal+Notes, P < .001). In adjusted analysis, compared to the No Portal group, the odds of loop closure were significantly higher for Portal Account Only (OR 1.2; 95% CI, 1.1-1.4), and Portal+Notes (OR 1.4; 95% CI, 1.3-1.6) groups. Beyond portal registration, note reading was independently associated with loop closure (P= .002).Discussion and conclusion: Compared to no portal registration, the odds of loop closure were 20% higher in tests/referrals for patients with a portal account, and 40% higher in tests/referrals for note readers, after controlling for sociodemographic and clinical factors. However, important safety gaps from unclosed loops remain, requiring additional engagement strategies.