Nudging Patients to Increase Shingles Vaccination

Shingles is a painful disease caused by reactivation of the varicella zoster (chickenpox) virus. About a third of adults in the US will develop shingles in their lifetime, with the highest prevalence in adults ages 50 and older. Roughly one in ten patients with shingles develops complications that can lead to long-term pain and inflammation). Shingrix, a two-shot vaccine series, is highly effective at preventing shingles and is recommended by the CDC for all adults ages 50 and over.

The present study will test whether sending patients messages encouraging them to ask about Shingrix at an upcoming primary care appointment increases vaccination rate relative to Passive Control (no messages). Additionally, four message arms will vary as a function of risk (message includes or does not include a statement telling patient they are at high risk for shingles because they are age 50+) and facts (message includes or does not include several facts about shingles and Shingrix), with the no-high-risk, no-facts arm designated as the Active Control arm.

Message arms will be crossed with two additional randomized variables: number of messages (2 messages or 3 messages) and cost information (the presence or absence of information about the cost of Shingrix in the final message).

Enrollment timing will vary by insurance group. Enrollment will begin with patients who have a Geisinger Health Plan (GHP) membership that allows them to get Shingrix at no cost (this includes the vast majority of GHP members), because existing data allow the study team to easily identify these patients and inform them about their Shingrix coverage in cost messages. Enrollment for patients who are not GHP members (and the few patients with a GHP plan that is not Shingrix eligible) will begin following the development of an automated internal process that will allow cost messages to include information about patients' individualized Shingrix insurance benefits. Alternatively, if development is delayed approximately 2 months or longer from the launch of enrollment for GHP members, the study team may decide in collaboration with Geisinger leadership to begin enrolling patients without GHP using a generic cost message (e.g., "Most patients can get Shingrix at no cost").

Enrollment for each insurance group (GHP members, non-GHP members) will begin with a 2-week pilot period, with a limited number of new patients (e.g., 100 to 200) enrolled per day in that insurance group (these patients will be randomly selected from the eligible patients). During the pilot period, the study team will communicate frequently with clinical partners to ensure there are no issues before full rollout. If issues arise, the pilot period may be extended. If the pilot period does not result in any changes to outreach, or involves only trivial changes, patients enrolled in the pilot period will be included in analysis. If there are more substantive changes to the outreach following the pilot period, patients enrolled during that period will be excluded from analysis.