DISCUSSION
cancers, colorectal cancer, HCC
CANCERS, HEPATITIS C, COLORECTAL CANCER, LIVER DISEASE
In this study, we found that mailed outreach with opt-out framing and a signed preorder doubles the participation in HCC surveillance. However, there was no additional effect due to the $20 unconditional financial incentive when added to the mailed outreach intervention. Importantly, we did not find differential effectiveness by sociodemographic characteristics in the subgroup analyses. In the exploratory analysis, we also found that more cancers were identified in the intervention group than in the control group.The effectiveness of the opt-out intervention may be explained by a few factors. First, it provided direct mail to remind patients about surveillance in a population health approach that does not rely on a visit to a specialist physician. Many patients may not be scheduled or may not attend a visit, which is the conventional opportunity for clinicians to remind patients about surveillance. The subgroup analysis showed that there may have been a greater effect among those without a visit during the trial period. This intervention provided an opportunity to participate during the COVID-19 pandemic, when patients may have missed routine visits. Additionally, the letter served as a nudge to remind patients if the ultrasound was ordered many months before but was forgotten. The letter also used preordering with opt-out framing, implying that participation in HCC surveillance is the default and the patient would have to actively choose not to participate. This has been shown to increase screening for colorectal cancer and hepatitis C in other trials.This study supports and adds to the literature on direct outreach for HCC surveillance. A trial at a safety net health system across all practices (not just specialty) evaluating mailed outreach with telephone follow-up showed a similar increase in one-time surveillance from 24.3% to 44.5%, with continued effectiveness over 18 months and a modest benefit from navigation.There are a few reasons why the financial incentive may not have increased response rate. First, the $20 incentive may not have been large enough to overcome any barriers for the patients to attend the ultrasound. Larger incentives of $100 have been shown to increase participation in screening colonoscopy among health system employees. The unconditional incentive may not have had as much effectiveness as other behaviorally informed incentives in this context, such as conditional or lottery-based incentives,The main strength of this study was the prospective randomization that controlled for unobserved variables and allowed for the evaluation of the effect of each specific intervention. It was conducted in a pragmatic design in partnership with routine clinical operations; therefore, the results can be generalized to other practices. We also evaluated a scalable approach to surveillance that can leverage EHR processes such as preordering and letter generation. A future state may be able to leverage a bulk ordering process that has been used in other preventive health exams. The study population had a high percentage of Black and Medicaid patients, groups who typically have known disparities and worse outcomes for liver disease.This study has some important limitations. While we showed the benefit of one-time surveillance, repeat surveillance over time is required to effectively reduce the burden of HCC, although prior studies have shown that this process can be repeated and sustained. This was conducted at an academic tertiary care center, so it may not translate to other care settings. Surveillance performed outside of the health system may have been missed. Although we conducted a chart review and allowed clinicians to opt-out of ineligible patients, we may have missed exams in the outcome ascertainment, and this could have biased toward higher effectiveness in the intervention arms. Additionally, this trial was conducted during the COVID-19 pandemic, although clinical visits and imaging appointments were available at that time.In summary, we found that sending mailed outreach with orders increased the response to HCC surveillance in a diverse population of patients followed by gastroenterology/hepatology specialists. This approach can be used by health systems to increase adherence to guidelines for population health management in patients with advanced liver disease. Additional research is needed to evaluate its long-term effectiveness in different populations.