TY - JOUR
T1 - Electronic Nudges to Increase Influenza Vaccination in Patients With Chronic Diseases
T2 - A Randomized Clinical Trial
AU - Johansen, Niklas Dyrby
AU - Vaduganathan, Muthiah
AU - Bhatt, Ankeet S
AU - Modin, Daniel
AU - Chatur, Safia
AU - Claggett, Brian L
AU - Janstrup, Kira Hyldekær
AU - Larsen, Carsten Schade
AU - Larsen, Lykke
AU - Wiese, Lothar
AU - Dalager-Pedersen, Michael
AU - Køber, Lars
AU - Solomon, Scott D
AU - Sivapalan, Pradeesh
AU - Jensen, Jens Ulrik Stæhr
AU - Martel, Cyril Jean-Marie
AU - Krause, Tyra Grove
AU - Biering-Sørensen, Tor
PY - 2024/12/10
Y1 - 2024/12/10
N2 - IMPORTANCE: Despite strong worldwide guideline recommendations, influenza vaccination rates remain suboptimal among young and middle-aged patients with chronic diseases. Effective scalable strategies to increase vaccination are needed.OBJECTIVE: To investigate whether electronically delivered letter-based nudges informed by behavioral science could increase influenza vaccination uptake among patients aged 18 to 64 years with chronic diseases.DESIGN, SETTING, AND PARTICIPANTS: Nationwide pragmatic registry-based randomized clinical implementation trial conducted between September 24, 2023, and May 31, 2024, enrolling all Danish citizens aged 18 to 64 years who met criteria for free-of-charge influenza vaccination in light of preexisting chronic disease. All trial data were sourced from nationwide administrative health registries.INTERVENTION: Randomized in 2.45:1:1:1:1:1:1 ratio to no letter (usual care) or 6 different behaviorally informed electronic letters.MAIN OUTCOMES AND MEASURES: The primary end point was receipt of influenza vaccination on or before January 1, 2024, assessed in 7 prespecified coprimary comparisons (all intervention groups pooled vs usual care and each individual intervention group vs usual care). Absolute risk difference in proportions and a crude relative risk were calculated for each comparison.RESULTS: A total of 299 881 participants (53.2% [159 454] female, median age, 52.0 [IQR, 39.8-59.0] years) were randomized. Compared with usual care, influenza vaccination rates were higher among those receiving any intervention letter (any intervention letter, 39.6% vs usual care, 27.9%; difference, 11.7 percentage points; 99.29% CI, 11.2-12.2 percentage points; P < .001). Each individual letter type significantly increased influenza vaccination with the largest effect sizes observed with a repeated letter sent 10 days after the initial letter (repeated letter, 41.8% vs usual care, 27.9%; difference, 13.9 percentage points; 99.29% CI, 13.1-14.7 percentage points; P < .001) and a letter emphasizing potential cardiovascular benefits of vaccination (cardiovascular gain, 39.8% vs usual care, 27.9%; difference, 11.9 percentage points; 99.29% CI, 11.1-12.7 percentage points; P < .001). Vaccination rates were improved across major subgroups.CONCLUSIONS AND RELEVANCE: In a nationwide randomized clinical implementation trial, electronically delivered letter-based nudges markedly increased influenza vaccination compared with usual care among young and middle-aged patients with chronic diseases. The results of this study suggest that simple, scalable, and cost-efficient electronic letter strategies may have substantial public health implications.TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT06030739.
AB - IMPORTANCE: Despite strong worldwide guideline recommendations, influenza vaccination rates remain suboptimal among young and middle-aged patients with chronic diseases. Effective scalable strategies to increase vaccination are needed.OBJECTIVE: To investigate whether electronically delivered letter-based nudges informed by behavioral science could increase influenza vaccination uptake among patients aged 18 to 64 years with chronic diseases.DESIGN, SETTING, AND PARTICIPANTS: Nationwide pragmatic registry-based randomized clinical implementation trial conducted between September 24, 2023, and May 31, 2024, enrolling all Danish citizens aged 18 to 64 years who met criteria for free-of-charge influenza vaccination in light of preexisting chronic disease. All trial data were sourced from nationwide administrative health registries.INTERVENTION: Randomized in 2.45:1:1:1:1:1:1 ratio to no letter (usual care) or 6 different behaviorally informed electronic letters.MAIN OUTCOMES AND MEASURES: The primary end point was receipt of influenza vaccination on or before January 1, 2024, assessed in 7 prespecified coprimary comparisons (all intervention groups pooled vs usual care and each individual intervention group vs usual care). Absolute risk difference in proportions and a crude relative risk were calculated for each comparison.RESULTS: A total of 299 881 participants (53.2% [159 454] female, median age, 52.0 [IQR, 39.8-59.0] years) were randomized. Compared with usual care, influenza vaccination rates were higher among those receiving any intervention letter (any intervention letter, 39.6% vs usual care, 27.9%; difference, 11.7 percentage points; 99.29% CI, 11.2-12.2 percentage points; P < .001). Each individual letter type significantly increased influenza vaccination with the largest effect sizes observed with a repeated letter sent 10 days after the initial letter (repeated letter, 41.8% vs usual care, 27.9%; difference, 13.9 percentage points; 99.29% CI, 13.1-14.7 percentage points; P < .001) and a letter emphasizing potential cardiovascular benefits of vaccination (cardiovascular gain, 39.8% vs usual care, 27.9%; difference, 11.9 percentage points; 99.29% CI, 11.1-12.7 percentage points; P < .001). Vaccination rates were improved across major subgroups.CONCLUSIONS AND RELEVANCE: In a nationwide randomized clinical implementation trial, electronically delivered letter-based nudges markedly increased influenza vaccination compared with usual care among young and middle-aged patients with chronic diseases. The results of this study suggest that simple, scalable, and cost-efficient electronic letter strategies may have substantial public health implications.TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT06030739.
KW - Adolescent
KW - Adult
KW - Chronic Disease
KW - Correspondence as Topic
KW - Cost-Effectiveness Analysis
KW - Denmark
KW - Female
KW - Humans
KW - Influenza Vaccines/administration & dosage
KW - Influenza, Human/complications
KW - Male
KW - Middle Aged
KW - Patient Acceptance of Health Care/psychology
KW - Vaccination/economics
KW - Young Adult
U2 - 10.1001/jama.2024.21060
DO - 10.1001/jama.2024.21060
M3 - Article
C2 - 39392741
SN - 0002-9955
VL - 332
SP - 1900
EP - 1911
JO - JAMA - Journal of the American Medical Association
JF - JAMA - Journal of the American Medical Association
IS - 22
ER -