Selection Bias Research Articles

Efficacy and safety of apheresis therapy in AQP4 antibody-positive NMOSD attack: A propensity score-matched cohort study.

Plasma exchange (PE) and immunoadsorption (IA) are recognized as effective ways to treat attacks in AQP4 antibody-positive NMOSD, but high-quality evidence was lacking. To evaluate the efficacy and safety of PE/IA plus intravenous methylprednisolone (IVMP) in NMOSD attacks using propensity scores to match IVMP as control. Patients were from a prospective observational cohort study. Stratification and interval propensity score matching (PSM) were used to reduce selection bias by matching baseline characteristics (gender, age, time to IVMP, EDSS at attack) between PE/IA + IVMP and IVMP group (in a ratio of 1:2). The primary endpoint of efficacy was EDSS change at 6 months. Adverse events and changes in laboratory tests were recorded. Four hundred and eleven attacks of 336 patients were screened for PSM, and 90 attacks (30 PE/IA + IVMP and 60 IVMP) were included in the analysis. There were significant differences in EDSS [6.25 vs. 6.75; IQR (4.50-8.38 vs. 5.00-8.00), p = 0.671] and visual acuity [median logMAR = 0.35 vs. 1.00; IQR (0.30-0.84 vs. 0.95-1.96), p = 0.002] change between two groups at 6 months. PE/IA + IVMP treatment demonstrated predictive capacity for good recovery as indicated by an area under the curve (AUC) of 0.726. Fibrinogen reduction was found during PE/IA + IVMP treatment [n = 15 (50.00%)], but no severe adverse events led to apheresis treatment discontinuation. After PSM analysis, IVMP+PE/IA in acute attack of NMOSD achieved better and continuous improvement in neurological function within 6 months compared with IVMP alone. PE/IA treatment showed a good safety profile.

The carbon premium: Correlation or causality? Evidence from S&P 500 companies

In the context of whether investors are aware of carbon-related risks, it is often hypothesized that there may be a carbon premium in the value of stocks of firms, conferring an abnormal excess value to firms’ shares as a form of compensation to investors for their transition risk exposure through the ownership of carbon instensive stocks. However, there is little consensus in the literature regarding the existence of such a premium. Moreover few studies have examined whether the correlation that is often observed is actually causal. The pertinent question is whether more polluting firms give higher returns or do firms with high returns have less incentive to decarbonize? In this study, we investigate whether firms’ emissions is causally linked to the presence of a carbon premium in a panel of 141 firms listed in the S&P500 index using fixed-effects analysis, with propensity score weighting to control for selection bias in which firms increase their emissions. We find that there is a statistically significant positive carbon premium associated with Scope 1 emissions, while there is no significant premium associated with Scope 2 emissions, implying that risks associated with direct emissions by the firm are priced, while bought emissions are not.

The impact of lobbying on managerial short-term resource adjustment decisions

This study examines the effect of political lobbying on firms' short-term resource adjustment decisions. Controlling for a wide range of known determinants of managerial cost behaviour, our results suggest that U.S. lobbying firms exhibit significantly less cost stickiness than non-lobbying firms. Lobbying reduces managers' "wait-and-see games" as they obtain preferential access to information on political and legislative processes. With early knowledge of impending (political and regulatory) threats and long-lasting downturns, managers can adjust unutilised capacity more swiftly. This effect is more pronounced for firms without alternative information channels like permanent exchange with regulators. Our findings hold for several robustness checks, for instance, controlling for potential sample selection bias or employing alternative measures of lobbying as well as (political) uncertainty and alternative samples.

Female foragers sometimes hunt, yet gendered divisions of labor are real: a comment on Anderson et al. (2023) The Myth of Man the Hunter

Gendered divisions of labor are a feature of every known contemporary hunter-gatherer (forager) society. While gender roles are certainly flexible, and prominent and well-studied cases of female hunting do exist, it is more often men who hunt. A new study (Anderson et al., 2023) surveyed ethnographically known foragers and found that women hunt in 79% of foraging societies, with big-game hunting occurring in 33%. Based on this single type of labor, which is one among dozens performed in foraging societies, the authors question the existence of gendered division of labor altogether. As a diverse group of hunter-gatherer experts, we find that claims that foraging societies lack or have weak gendered divisions of labor are contradicted by empirical evidence. We conducted an in-depth examination of the data and methods of Anderson et al. (2023), finding evidence of sample selection bias and numerous coding errors undermining the paper's conclusions. Anderson et al. (2023) have started a useful dialogue to ameliorate the potential misconception that women never hunt. However, their analysis does not contradict the wide body of empirical evidence for gendered divisions of labor in foraging societies. Furthermore, a myopic focus on hunting diminishes the value of contributions that take different forms and downplays the trade-offs foragers of both sexes routinely face. We caution against ethnographic revisionism that projects Westernized conceptions of labor and its value onto foraging societies.

Association of a 40-Gene Expression Profile With Risk of Metastatic Disease Progression of Cutaneous Squamous Cell Carcinoma (cSCC) and Specification of Benefit of Adjuvant Radiation Therapy

PurposeAdjuvant radiation therapy (ART) for cutaneous squamous cell carcinoma (cSCC) is recommended based on a number of wide-ranging clinicopathologic features, which encompass a broad array of patients. The 40-gene expression profile (40-GEP) test classifies cSCC tumors into low (Class 1) or higher (Class 2A) or highest (Class 2B) risk of nodal and/or distant metastasis. This study's hypotheses are 1) local recurrence is associated with metastatic disease progression, and 2) 40-GEP, by identifying high risk for metastasis, could predict a metastasis-specific benefit from ART. MethodsSamples were obtained from 920 patients (ART-untreated: 496 Class 1, 335 Class 2A, 33 Class 2B; ART-treated: 11 Class 1, 35 Class 2A, 10 Class 2B) who were matched on clinical risk factors and stratified by ART status, to create 49 matched patient strata. To control for the variety of characteristics and treatment selection bias, randomly sampled pairs of matched ART and non-ART patients comprising 10,000 resampled cohorts were each analyzed for 5-year metastasis-free survival and predicted time to metastatic event. ResultsOf 96 patients experiencing local recurrence, 56.3% experienced metastasis; of those experiencing both, 88.9% had local recurrence before (75.9%) or concurrently (13.0%) with metastasis. After matching for clinicopathological risk, median 5-year disease progression rates for resampled cohorts demonstrated approximately 50% improvement for Class 2B ART-treated as compared to ART-untreated cohorts. Class 2B ART-treated cohorts had a 5-fold delay in predicted time to metastatic event and deceleration of disease progression as compared to ART-untreated cohorts (Kolmogorov-Smirnov test, p<0.01); this was not observed for Class 1 or 2A patients (p>0.05 for each). No risk factor or staging system combined with ART status identified groups that would benefit from ART as well as 40-GEP. Conclusion40-GEP identifies patients at highest risk of nodal/distant metastasis who may derive greatest benefit from ART, as well as patients who may have clinical indications for ART but are at low risk of metastasis. Compared to current guidelines, 40-GEP could provide greater specificity concerning the benefit of ART in individual patients.

Effectiveness and cost-effectiveness of community-based directly observed treatment (DOT) versus health facility-based DOT of tuberculosis in Africa: protocol for a systematic review and meta-analysis

BackgroundTuberculosis (TB) remains a significant global health challenge, especially prevalent in the WHO African region. The WHO’s End TB Strategy emphasises effective treatment approaches such as directly observed therapy (DOT),...

Moderating effect of shift work on sleep and depression in individuals at high risk of bipolar disorder

BackgroundSocial Zeitgeber Theory posits that disruptions in social rhythms can increase susceptibility to bipolar disorder (BD). Shift work (SW) is one of the external factors that cause instability in social rhythms and the sleep-wake cycle. This study evaluated the moderating influences of SW on the risks of BD and sleep-related parameters and depressive symptoms. Furthermore, we evaluated the specific work schedules including daytime, nighttime, and regular and irregular rotating SW. MethodsAn online survey was administered to 6665 participants, with 3379 (50.7 %) classified as individuals with high scores of Mood Disorder Questionnaire (MDQ). The survey included the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Scale (ISI), Epworth Sleepiness Scale (ESS), and Center for Epidemiologic Studies Depression Scale (CES-D). ResultsA multivariate regression model revealed significant interactive effects of MDQ positivity and SW on PSQI, ISI, and CES-D scores, but not ESS scores. In a secondary analysis of the high MDQ screen group, daytime workers had lower scores in sleep disturbances and depressive symptoms compared to those engaged in other forms of SW. LimitationsOnline surveys were accessible voluntarily, leading to potential selection bias. Cross-sectional data identified associations, not causal relationships. Only a self-reported questionnaire was used. ConclusionsOur findings emphasize the advantages of a daytime work schedule for individuals at high risk of BD. In accordance with the principles of social rhythm interpersonal therapy, sleep interventions for individuals at high risk of BD should include the maintenance of a consistent daytime schedule.

Shared and Specific Neural Correlates of Attention Deficit Hyperactivity Disorder and Autism Spectrum Disorder: A Meta-Analysis of 243 Task-Based Functional MRI Studies.

To investigate shared and specific neural correlates of cognitive functions in attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), the authors performed a comprehensive meta-analysis and considered a balanced set of neuropsychological tasks across the two disorders. A broad set of electronic databases was searched up to December 4, 2022, for task-based functional MRI studies investigating differences between individuals with ADHD or ASD and typically developing control subjects. Spatial coordinates of brain loci differing significantly between case and control subjects were extracted. To avoid potential diagnosis-driven selection bias of cognitive tasks, the tasks were grouped according to the Research Domain Criteria framework, and stratified sampling was used to match cognitive component profiles. Activation likelihood estimation was used for the meta-analysis. After screening 20,756 potentially relevant references, a meta-analysis of 243 studies was performed, which included 3,084 participants with ADHD (676 females), 2,654 participants with ASD (292 females), and 6,795 control subjects (1,909 females). ASD and ADHD showed shared greater activations in the lingual and rectal gyri and shared lower activations in regions including the middle frontal gyrus, the parahippocampal gyrus, and the insula. By contrast, there were ASD-specific greater and lower activations in regions including the left middle temporal gyrus and the left middle frontal gyrus, respectively, and ADHD-specific greater and lower activations in the amygdala and the global pallidus, respectively. Although ASD and ADHD showed both shared and disorder-specific standardized neural activations, disorder-specific activations were more prominent than shared ones. Functional brain differences between ADHD and ASD are more likely to reflect diagnosis-related pathophysiology than bias from the selection of specific neuropsychological tasks.

The impact of rural living environment improvement programs on the subjective well-being of rural residents in China

Increasing people’s subjective well-being (SWB) remains a critical challenge for all countries. However, few studies have been dedicated to examining the influence of environmental governance programs on SWB, especially in developing and non-democratic societies. This paper aims to fill this void by taking the Rural Living Environment Improvement (RLEI) program in China—the largest rural living environment governance program in history, as an example to understand the role of environmental governance programs in SWB in the world’s biggest developing and non-democratic country. Based on 3747 individual samples from the China Labor-force Dynamics Survey database, we found that RLEI can significantly improve rural residents’ SWB. This effect remains significant after using the propensity score matching method and the instrumental variable approach to address potential selection bias and endogenous problems. The indirect analysis shows that RLEI can increase rural residents’ SWB mainly through improving their income, consumption expenditure, and health. Compared with rural sewage and livestock manure RLEI programs, rural waste RLEI program has a greater enhanced impact on rural residents’ SWB. The monetary value of RLEI based on the life satisfaction approach shows that the resulting improvement in rural residents’ SWB created by RLEI is almost equivalent to the effect of household income. While the monetary value of rural sewage, livestock manure, and rural waste RLEI program is equivalent to 1.2, 3.67, and 1.1 times the effect of household income. Heterogeneity analysis indicates that RLEI has a greater positive impact on SWB for junior and old-aged, low-educated, Midwestern and Northeastern, and working rural residents.

The impact of urbanization and economic development on health insurance performance: Evidence from China

Many previous studies find no significant effect of health insurance on health outcome in rural areas of China. Many researchers believe this could be because of the characteristics of health care provision in those areas. In this paper, we aim to examine if urbanization will change the situation. Our research question focuses on if urbanization will change the participation and performance of health insurance on health outcome in a positive direction. Using a longitudinal sample drawn from the China Health and Nutrition Survey (CHNS), we employed multiple estimation strategies for multiple waves to handle the potential selection bias. We find that urbanization factors such as population density, transportations and housing are associated with probability of insurance participation. That is, urbanization related factors tend to increase people’s willingness of insurance participation. We also conclude that urbanization improves the performance of insurance on self-reported health outcome. Results show that the health insurance has a significant positive impact on health production in urbanized areas. Health insurance in general increases the probability of health care utilization for all areas. However, it does not lead to a significant improvement in the health outcomes in under urbanized areas because of the health provision quality or characteristics of health insurance coverage in those areas.

Treatment strategies for stage IA non-small cell lung cancer: A SEER-based population study.

There are various therapeutic methods for treating stage IA (T1N0M0) non-small cell lung cancer (NSCLC), but no studies have systematically assessed multiple treatments to determine the most effective therapy. Stage IA NSCLC patient data collected between 2004 and 2018 were gathered from the Surveillance, Epidemiology, and End Results (SEER) database. Treatment modalities included observation, chemotherapy alone (CA), radiation alone (RA), radiation+chemotherapy (RC), surgery alone (SA), surgery+chemotherapy (SC), surgery+radiation (SR) and surgery+radiation+chemotherapy (SRC). Comparisons were made of overall survival (OS) and lung cancer-specific survival (LCSS) among patients based on different therapeutic methods by survival analysis. Ultimately, 89147 patients with stage IA NSCLC between 2004 and 2018 were enrolled in this study. The order of multiple treatment modalities based on the hazard ratio (HR) for OS for the entire cohort revealed the following results: SA (HR: 0.20), SC (HR: 0.25), SR (HR: 0.42), SRC (HR: 0.46), RA (HR: 0.56), RC (HR: 0.72), CA (HR: 0.91) (P<0.001), and observation (HR: Ref). The SA group had the best OS and LCSS, and similar results were found in most subgroup analyses (all P<0.001). The order of surgical modalities based on the HR for OS for the entire cohort revealed the following results: lobectomy (HR: 0.32), segmentectomy (HR: 0.41), wedge resection (HR: 0.52) and local tumor destruction (HR: Ref). Lobectomy had the best effects on OS and LCSS, and similar results were found in all subgroup analyses (all P<0.001). SA appeared to be the optimal treatment modality for patients with stage IA NSCLC, and lobectomy was associated with the best prognosis. There may be some indication and selection bias in our study, and the results of this study should be confirmed in a prospective study.

Elucidating the multichromosomal structure within the Brasenia schreberi mitochondrial genome through assembly and analysis

Brasenia schreberi, a plant species traditionally utilized in Chinese medicine and cuisine, represents an early evolutionary stage among flowering plants (angiosperms). While the plastid genome of this species has been published, its mitochondrial genome (mitogenome) has not been extensively explored, with a notable absence of thorough comparative analyses of its organellar genomes. In our study, we had assembled the entire mitogenome of B. schreberi utilizing the sequencing data derived from both Illumina platform and Oxford Nanopore. The B. schreberi mitogenome mostly exists as six circular DNA molecules, with the largest being 628,257 base pairs (bp) and the smallest 110,220 bp, amounting to 1.49 megabases (Mb). Then we annotated the mitogenome of B. schreberi. The mitogenome encompasses a total of 71 genes: 40 of these are coding proteins genes (PCGs), 28 are genes for transfer RNA (tRNA), and the remaining 3 are genes for ribosomal RNA (rRNA). In the analysis of codon usage, we noted a unique codon preference specific to each amino acid. The most commonly used codons exhibited an average RSCU of 1.36, indicating a noticeable bias in codon selection. In the repeat sequence analysis, a total of 553 simple sequence repeats (SSRs) were identified, 1,822 dispersed repeats (comprising 1,015 forward and 807 palindromic repeats), and 608 long terminal repeats (LTRs). Additionally, in the analysis of homologous sequences between organelle genomes, we detected 38 homologous sequences derived from the plastid genome, each exceeding 500 bp, within the B. schreberi mitochondrial genome. Notably, ten tRNA genes (trnC-GCA, trnM-CAU, trnI-CAU, trnQ-UUG, trnN-GUU, trnT-GGU, trnW-CCA, trnA-UGC, trnI-GAU, and trnV-GAC) appear to have been completely transferred from the chloroplast to the mitogenome. Utilizing the Deepred-mt to predict the RNA editing sites in the mitogenome, we have identified 675 high-quality RNA editing sites in the 40 mitochondrial PCGs. In the final stage of our study, we performed an analysis of colinearity and inferred the phylogenetic relationship of B. schreberi with other angiosperms, utilizing the mitochondrial PCGs as a basis. The results showed that the non-coding regions of the B. schreberi mitogenome are characterized by an abundance of repetitive sequences and exogenous sequences, and B. schreberi is more closely related with Euryale ferox.

The Impact of Boardroom Diversity on Company Performance Using Propensity Score-Based Estimators (PSM)

This study investigates the impact of boardroom diversity on firm performance utilizing propensity score- based estimators (PSM). Drawing from a comprehensive literature review, it is established that gender diversity in boardrooms positively influences firm performance, particularly in the financial sector. Using panel data from 503 UK firms over the period of 2015-2017, the analysis focuses on key performance indicators such as market capitalization and leverage. Employing various econometric models, including binary treatment and augmented inverse-probability weighting, the study reveals significant positive effects of female board- room participation on firm performance. Specifically, an increase in female representation is associated with higher market capitalization and an increased leverage ratio, indicating a propensity for riskier investments. Furthermore, the study explores the nuanced effects of different levels of female director representation, highlighting the importance of substantial gender diversity for optimal firm performance. Despite potential limitations such as treatment selection bias and omitted variable bias, the models demonstrate robustness and contribute to the existing literature by providing empirical evidence supporting the positive impact of boardroom diversity on company performance.

Credit constraints and risk exposure in scaled farming: insights from East China

Credit constraints and risk exposure in scaled farming: insights from East China

Poor evidence for poor R wave progression in coronary disease: A scoping review

BackgroundPoor R wave progression (PRWP) and reversed R wave progression (RRWP) have long been noted in electrocardiograms as potential indicators of anterior wall fibrosis or chronic coronary artery disease; however, the quantity and quality of evidence supporting these associations warrants closer examination. ObjectiveThe aim of this scoping review is to assess the breadth of evidence regarding the diagnostic significance of PRWP and RRWP, explore the extent of research, study populations and methodologies, and the presence of gaps in knowledge regarding these electrocardiographic phenomena and their association with coronary diseases. DesignWe conducted a comprehensive search across PubMed, Web of Science, and Scopus, covering literature on PRWP or RRWP in the context of myocardial infarction, ischemia, or fibrosis from any time period and in any language. ResultsA total of 20 studies were included in this review, highlighting the severe paucity of data. No high-quality accuracy studies have been identified, and existing research suffers from methodological issues, in particular selection bias. Prevalence and prognostic studies showed significant heterogeneity in terms of definitions and outcomes, which contributes to an alarming risk of bias. ConclusionsThe lack of solid evidence for PRWP and RRWP as diagnostic markers for acute and chronic coronary artery disease necessitates caution in clinical interpretation. Future research should focus on well-designed case-control studies to clarify the diagnostic accuracy of these markers. Until robust evidence is available, the reliance on PRWP/RRWP for diagnosing anterior infarction should be discouraged, reflecting a gap between clinical practice and evidence-based medicine.

Design and implementation of community consultation for research conducted under exception from informed consent regulations for the PreVent and the PreVent 2 trials: Changes over time and during the COVID-19 pandemic.

Emergency clinical research has played an important role in improving outcomes for acutely ill patients. This is due in part to regulatory measures that allow Exception From Informed Consent (EFIC) trials. The Food and Drug Administration (FDA) requires sponsor-investigators to engage in community consultation and public disclosure activities prior to initiating an Exception From Informed Consent trial. Various approaches to community consultation and public disclosure have been described and adapted to local contexts and Institutional Review Board (IRB) interpretations. The COVID-19 pandemic has precluded the ability to engage local communities through direct, in-person public venues, requiring research teams to find alternative ways to inform communities about emergency research. The PreVent and PreVent 2 studies were two Exception From Informed Consent trials of emergency endotracheal intubation, conducted in one geographic location for the PreVent Study and in two geographic locations for the PreVent 2 Study. During the period of the two studies, there was a substantial shift in the methodological approach spanning across the periods before and after the pandemic from telephone, to in-person, to virtual settings. During the 10 years of implementation of Exception From Informed Consent activities for the two PreVent trials, there was overall favorable public support for the concept of Exception From Informed Consent trials and for the importance of emergency clinical research. Community concerns were few and also did not differ much by method of contact. Attendance was higher with the implementation of virtual technology to reach members of the community, and overall feedback was more positive compared with telephone contacts or in-person events. However, the proportion of survey responses received after completion of the remote, live event was substantially lower, with a greater proportion of respondents having higher education levels. This suggests less active engagement after completion of the synchronous activity and potentially higher selection bias among respondents. Importantly, we found that engagement with local community leaders was a key component to develop appropriate plans to connect with the public. The PreVent experience illustrated operational advantages and disadvantages to community consultation conducted primarily by telephone, in-person events, or online activities. Approaches to enhance community acceptance included partnering with community leaders to optimize the communication strategies and trust building with the involvement of Institutional Review Board representatives during community meetings. Researchers might need to pivot from in-person planning to virtual techniques while maintaining the ability to engage with the public with two-way communication approaches. Due to less active engagement, and potential for selection bias in the responders, further research is needed to address the costs and benefits of virtual community consultation and public disclosure activities compared to in-person events.

Increasing broad-spectrum aquatic invasive species early detection program efficiency through biased site selection and gear allocation

AbstractInvasive species cause severe environmental and economic damage throughout the globe. Aside from preventing their introduction, early detection of newly introduced species is the most successful method to prevent their establishment, spread, and eventual negative impacts. Broad-spectrum monitoring for the early detection of novel non-native species is oftentimes heavily burdened by the inherent difficulty in maximizing the detection probabilities of numerous high priority species simultaneously with only finite resources. We attempted to increase the efficiency of broad-spectrum monitoring in four locations across Lake Erie (USA)—the Detroit River, Maumee Bay, Sandusky Bay, and Cleveland—by targeting our site and gear selections to maximize overall species richness and detection rates of rare and non-native species, with the results compared to a random sampling design. Overall species richness was significantly higher in all four locations, while non-native species detection rates were significantly higher in every location except for Cleveland. Detection rates of rare species was significantly higher in Maumee Bay only. Our results indicate this selective sampling design is more likely to detect a newly introduced non-native species than a random sampling design and are in support of the established literature for broad-spectrum monitoring for novel aquatic invasive species.

Sustainable practices in cocoa production. The role of certification schemes and farmer cooperatives

In Côte d'Ivoire and Ghana, many small-scale cocoa producers cultivate cocoa in unshaded or low-shaded plots, leading to challenges such as reduced biodiversity, soil fertility depletion, and increased soil erosion. To assess the adoption of sustainable agricultural practices in the cocoa sector, we develop a scale that incorporates dimensions of agroforestry, soil conservation, pest and disease management and farm sanitation. Using data from >1700 cocoa producers, we examine farmer participation in cooperatives and three main certification schemes (incl. Fairtrade, Rainforest Alliance and Organic) to understand their roles in promoting sustainable practices. We apply a multinomial endogenous switching regression model to control for potential selection bias and estimate the impact of participating in certification schemes, farmer cooperatives or both. In Côte d'Ivoire, econometric results show that joint participation in both a certification scheme and a farmer cooperative is associated with a significantly higher sustainability score. In Ghana, certification scheme membership shows the highest effect.

Association between Covishield vaccine and menstrual disturbance. Findings from a cross-sectional study among participants of Zero TB cohort in India

BackgroundThe association between covid-19 vaccine and menstrual disturbance is unclear. MethodsAn in-person cross-sectional survey among female members ≥ 18 years enrolled in an ongoing Zero TB prospective cohort in Northern India who had received one or two doses of covid-19 vaccine was conducted to study the characteristics and association of menstrual disturbance within six months of receiving Covishield. ResultsBetween June 29 and September 5, 2021, 339 females ≥ 18 years of age were administered the survey. Median age was 30 (IQR: 22–39) years; 84 % were between 18 and 49 and 16 % were ≥ 50 years old. There were 152 college students, 27 healthcare workers, and 160 nuns. Forty-two women (12 %) had received one dose and 297 (88 %) had received two doses of Covishield. Overall, 66 (20 %) women reported experiencing menstrual disturbance after receiving Covishield vaccine. The problems included early menstruation: 6 % (n = 19/339); late menstruation: 4 % (n = 14/339); and heavier bleeding: 5 % (n = 17/339). Disturbances lasted for less than seven days and cycles normalized in 1–3 months. There was no post-menopausal bleeding. There was no significant difference in menstrual disturbance based on receiving one vs. two doses of Covishield (OR: 1.58; 95 % CI: 0.55–4.57; p = 0.381). History of SARS-CoV-2 infection was not associated with the development of menstrual disturbance among the vaccinees (OR: 0.63; 95 % CI: 0.24–1.73; p = 0.379). Presence of emotional disturbance at baseline (OR: 31; 95 % CI: 3.52–267; p = 0.002) or previous history of dysmenorrhea (OR: 41; 95 % CI: 8.7–196; p < 0.001) was associated with menstrual disturbance in the vaccinees, indicating their potential to confound or bias study results. ConclusionMenstrual problems were reported by Covishield vaccinees, but they were minor and reversible within three months and do not constitute a ground for vaccine hesitancy. Studies designed to assess causal link taking care to avoid selection bias or confounding are needed.

Coronavirus disease 2019 vaccination among young children: Associations with fathers’ and mothers’ influenza vaccination status

ObjectivesTo examine the association between parents’ influenza vaccination and their children’s coronavirus disease 2019 (COVID-19) vaccination status. MethodsParticipants included father-mother dyads from Fathers & Families, a cohort of fathers and their co-parents living in the United States. Parents’ influenza vaccination status and children’s COVID-19 vaccination status were reported from June 2022-July 2023. Logistic regression was used to examine the association between parental influenza vaccination (both parents vs. neither parent vs. mother only vs. father only vaccinated) and child COVID-19 vaccination (received at least 1 vs. 0 doses). Models were adjusted for recruitment site, income, parent education, child race/ethnicity, child age, and childcare enrollment. Inverse probability weighting was used to account for selection bias into the father-mother dyad sample. ResultsChildren were predominately non-Hispanic White (56 %) and aged 3–5 years (62 %). In most households, both parents (64 %) received the influenza vaccine and half (53 %) of children received the COVID-19 vaccine. One-in-four fathers (23 %) lacked knowledge about their child’s COVID-19 vaccination eligibility. Compared to children with two unvaccinated parents, having only their father (adjusted odds ratio [AOR] = 2.84, 95 % confidence interval [CI]: 1.52–5.36), only their mother (AOR = 4.04, 95 % CI: 2.16–7.68), and both parents (AOR = 10.33, 95 % CI: 6.29–17.53) vaccinated against influenza was associated with higher odds of children receiving the COVID-19 vaccine. ConclusionsFather and mother influenza vaccination is associated with child COVID-19 vaccination. Given many fathers were unaware their child was eligible for the COVID-19 vaccine, it is critical to tailor vaccine messaging for fathers.