Optimal timing of influenza vaccination in young children: population based cohort study.

OBJECTIVE: To assess optimal timing of influenza vaccination in young children. DESIGN: Population based cohort study. SETTING: United States. PARTICIPANTS: Commercially insured children aged 2-5 years who were vaccinated against influenza during 2011-18. MAIN OUTCOME MEASURE: Rates of diagnosis of influenza among children who were vaccinated against influenza, by birth month. RESULTS: Overall, 819 223 children aged 2-5 received influenza vaccination. Children vaccinated in November and December were least likely to have a diagnosis of influenza, a finding that may be confounded by unmeasured factors that influence the timing of vaccination and risk of influenza. Vaccination commonly occurred on days of preventive care visits and during birth months. Children born in October were disproportionately vaccinated in October and were, on average, vaccinated later than children born in August and earlier than those born in December. Children born in October had the lowest rate of influenza diagnosis (for example, 2.7% (6016/224 540) versus 3.0% (6462/212 622) for those born in August; adjusted odds ratio 0.88, 95% confidence interval 0.85 to 0.92). CONCLUSIONS: In a quasi-experimental analysis of young children vaccinated against influenza, birth month was associated with the timing of vaccination through its influence on the timing of preventive care visits. Children born in October were most likely to be vaccinated in October and least likely to have a diagnosis of influenza, consistent with recommendations promoting October vaccination.

Organ Donation and Transplants During Major US Motorcycle Rallies.

Importance: Large-scale motorcycle rallies attract thousands of attendees and are associated with increased trauma-related morbidity and mortality. Objective: To examine the association of major US motorcycle rallies with the incidence of organ donation and transplants. Design, Setting, and Participants: This population-based, retrospective cross-sectional study used data from the Scientific Registry of Transplant Recipients for deceased organ donors aged 16 years or older involved in a motor vehicle crash and recipients of organs from these donors from March 2005 to September 2021. Exposure: Dates of 7 large US motorcycle rallies and regions near these events. Main Outcomes and Measures: The main outcomes were incidence of motor vehicle crash-related organ donation and number of patients receiving a solid organ transplant from these donors. An event study design was used to estimate adjusted rates of organ donation during the dates of 7 major US motorcycle rallies compared with the 4 weeks before and after the rallies in rally-affected and rally-unaffected (control) regions. Donor and recipient characteristics and metrics of organ quality were compared between rally and nonrally dates. Results: The study included 10 798 organ donors (70.9% male; mean [SD] age, 32.5 [13.7] years) and 35 329 recipients of these organs (64.0% male; 49.3 [15.5] years). During the rally dates, there were 406 organ donors and 1400 transplant recipients. During the 4 weeks before and after the rallies, there were 2332 organ donors and 7714 transplant recipients. Donors and recipients during rally and nonrally dates were similar in demographic and clinical characteristics, measures of organ quality, measures of recipient disease severity, and recipient waiting time. During rallies, there were 21% more organ donors per day (incidence rate ratio [IRR], 1.21; 95% CI, 1.09-1.35; P = .001) and 26% more transplant recipients per day (IRR, 1.26; 95% CI, 1.12-1.42; P < .001) compared with the 4 weeks before and after the rallies in the regions where they were held. Conclusions and Relevance: In this cross-sectional study, major motorcycle rallies in the US were associated with increased incidence of organ donation and transplants. While safety measures to minimize morbidity and mortality during motorcycle rallies should be prioritized, this study showed the downstream association of these events with organ donation and transplants.

An Empirical Assessment of Reviewer 2.

According to research lore, the second peer reviewer (Reviewer 2) is believed to rate research manuscripts more harshly than the other reviewers. The purpose of this study was to empirically investigate this common belief. We measured word count, positive phrases, negative phrases, question marks, and use of the word "please" in 2546 open peer reviews of 796 manuscripts published in the British Medical Journal. There was no difference in the content of peer reviews between Reviewer 2 and other reviewers for word count (630 vs 606, respectively, P = .16), negative phrases (8.7 vs 8.4, P = .29), positive phrases (4.2 vs 4.1, P = .10), question marks (4.8 vs 4.6, P = .26), and uses of "please" (1.0 vs 1.0, P = .86). In this study, Reviewer 2 provided reviews of equal sentiment to other reviewers, suggesting that popular beliefs surrounding Reviewer 2 may be unfounded.

Association of Maternal Cervical Disease With Human Papillomavirus Vaccination Among Offspring.

Importance: Barriers to childhood vaccination against vaccine-preventable diseases, such as those due to human papillomavirus (HPV), are well known. However, the role of salience bias-the change in perception of risk due to increased familiarity with the outcome-in decisions to vaccinate children has not been explicitly studied. Objective: To assess for salience bias in parental decisions to vaccinate children. Design, Setting, and Participants: This retrospective cohort study used a time-to-event (survival) analysis to compare vaccination rates of children whose mothers had a history of cervical cancer or a cervical biopsy, who have experienced adverse vaccine-preventable outcomes, and for whom vaccination may be more salient, with a control group of children whose mothers had no such history. Participants were accrued from the MarketScan Commercial Database, including US children who turned 11 years old, when HPV vaccination is recommended, from January 1, 2014, to December 31, 2018. Data were analyzed from December 29, 2020, to September 17, 2021. Exposures: Maternal history of cervical cancer or cervical biopsy. Main Outcomes and Measures: Vaccination against HPV. Results: A total of 757 428 children (370 878 girls [49.0%] and 386 550 boys [51.0%]) were identified, of whom 38 366 had mothers with a history of cervical biopsy alone and 1084 had mothers with a history of cervical cancer. Overall, 54.2% of children (55.7% of girls and 52.7% of boys) received at least 1 vaccination by 16 years of age. In a time-to-event analysis, HPV vaccination did not differ between children whose mothers had cervical cancer vs those whose mothers did not (hazard ratio [HR] for girls, 0.99 [95% CI, 0.86-1.13]; HR for boys, 1.08 [95% CI, 0.94-1.24]). Maternal history of cervical biopsy was associated with a minimally increased hazard of vaccination (HR for girls, 1.06 [95% CI, 1.04-1.09]; HR for boys, 1.04 [95% CI, 1.01-1.06]). There were no clinically meaningful differences between groups for the tetanus/diphtheria/acellular pertussis and meningococcal vaccinations, which are also recommended at 11 years of age. Conclusions and Relevance: In this analysis of salience bias in childhood vaccination decisions, mothers' personal history of cervical cancer or cervical biopsy was not associated with greater vaccination rates among children against HPV. These findings suggest that salience of vaccine-preventable outcomes may not have a major impact on childhood vaccine hesitancy in HPV; the role of salience should be investigated for other vaccines.