Survival Bias Research Articles

Microentrepreneurs in the gig economy: who they are, what they do, and why they do it

Purpose Gig microentrepreneurs are individuals who have embraced short-term gigs as an entrepreneurial agency for both financial and social livelihood. Based on surveys in 2020 and 2023, the research reported here presents a comprehensive, empirical portrait of two cohorts of gig microentrepreneurs. This portrait captures the similarities and differences of gig microentrepreneurs in terms of offline and online business models and the nature of gig work. Recognizing that there is not a “typical” gig microentrepreneur will help ensure that this gig business model continues to evolve without boundaries in terms of demographics, motivations and behavior and will enable marketing and entrepreneurship scholars to better assist in entrepreneurial growth and development. The purpose of this paper is to gain a better understanding of the gig microentrepreneur regardless of the nature of the gig work. Design/methodology/approach The research involved two separate surveys in the USA. The first survey took place in July 2020, and the second survey took place in April 2023 after major changes had taken place in the economy and in society (e.g. the COVID pandemic). Both surveys used samples generated by Dynata, an online consumer panel company with access to more than 70 million consumers worldwide who have agreed to participate as panel members. Findings The surveys provided answers to questions about the demographic and behavioral aspects of gig microentrepreneurs, including who they are, the number and type of gig activities in which they participate, the financial livelihood generated from gig income, the social livelihood inherent in gig work and dissatisfaction with being a microentrepreneur in the gig economy. These findings produced insights into why individuals engage in gig activities and the positive and negative impacts of that engagement. Based on the findings, nuances and trends within the gig economy and among gig microentrepreneurs are identified and discussed. Research limitations/implications The research limitations include lack of generalizability outside of the USA, use of panel data and survivor bias. Practical implications Consumers, gig microentrepreneurs, companies and government agencies can benefit from the growth in the gig economy. The vast array of gig activities in which gig microentrepreneurs engage clearly shows the need for an on-demand workforce. There are both economic and societal benefits to having a labor-force that can meet a breadth of demands with varying timeframes. Social implications Whether gig microentrepreneurs are engaging in gig work to augment their income because of economic insecurity or for intrinsic reasons, the motivations and behaviors of the gig microentrepreneurs are indicative of the talent and resources needed to keep the US economy moving forward positively. Originality/value As noted by several scholars conducting research on the gig economy, little is known about gig microentrepreneurs – who they are, what they do and why they do it. Current research on the gig economy tends to focus on online platform companies. This research offers an exploratory look at microentrepreneurs who engage in gig activities both online and offline without geographic or technological boundaries.

Addressing immortal time bias in precision medicine: Practical guidance and methods development.

To compare theoretical strengths and limitations of common immortal time adjustment methods, propose a new approach using multiple imputation (MI), and provide practical guidance for using MI in precision medicine evaluations centered on a real-world case study. Methods comparison, guidance, and real-world case study based on previous literature. We compared landmark analysis, time-distribution matching, time-dependent analysis, and our proposed MI application. Guidance for MI spanned (1) selecting the imputation method; (2) specifying and applying the imputation model; and (3) conducting comparative analysis and pooling estimates. Our case study used a matched cohort design to evaluate overall survival benefits of whole-genome and transcriptome analysis, a precision medicine technology, compared to usual care for advanced cancers, and applied both time-distribution matching and MI. Bootstrap simulation characterized imputation sensitivity to varying data missingness and sample sizes. Case study used population-based administrative data and single-arm precision medicine program data from British Columbia, Canada for the study period 2012 to 2015. While each method described can reduce immortal time bias, MI offers theoretical advantages. Compared to alternative approaches, MI minimizes information loss and better characterizes statistical uncertainty about the true length of the immortal time period, avoiding false precision. Additionally, MI explicitly considers the impacts of patient characteristics on immortal time distributions, with inclusion criteria and follow-up period definitions that do not inadvertently risk biasing evaluations. In the real-world case study, survival analysis results did not substantively differ across MI and time distribution matching, but standard errors based on MI were higher for all point estimates. Mean imputed immortal time was stable across simulations. Precision medicine evaluations must employ immortal time adjustment methods for unbiased, decision-grade real-world evidence generation. MI is a promising solution to the challenge of immortal time bias.

Evidence of survival bias in the association between APOE-Є4 and age at ischemic stroke onset.

Large genome-wide association studies (GWASs) using case-control study designs have now identified tens of loci associated with ischemic stroke (IS). As a complement to these studies, we performed GWAS in a case-only design to identify loci influencing the age at onset (AAO) of ischemic stroke. Analyses were conducted in a discovery cohort of 10,857 ischemic stroke cases using a linear regression framework. We meta-analyzed all SNPs with p-value <1 x 10-5 in a sexcombined or sex-stratified analysis using summary data from two additional replication cohorts. In the women-only meta-analysis, we detected significant evidence for the association of AAO with rs429358, an exonic variant in apolipoprotein E (APOE) that encodes for the APOE-Є4 allele. Each copy of the rs429358:T>C allele was associated with a 1.29-year earlier stroke AAO (meta p-value = 2.48 x 10-11). This APOE variant has previously been associated with increased mortality and ischemic stroke AAO. We hypothesized that the association with AAO may reflect a survival bias attributable to an age-related decrease in mortality among APOE-Є4 carriers and have no association to stroke AAO per se. A simulation study showed that a variant associated with overall mortality might indeed be detected with an AAO analysis. A variant with a 2-fold increase in mortality risk would lead to an observed effect of AAO that is comparable to what we found. In conclusion, we detected a robust association of the APOE locus with stroke AAO and provided simulations to suggest that this association may be unrelated to ischemic stroke per se but related to a general survival bias.

Phosphodiesterase 5 Inhibitor Treatment Is Associated With Improved Survival in Pulmonary Hypertension Associated With COPD in the Pulmonary Vascular Research Institute GoDeep Meta-Registry

BackgroundPatients with COPD frequently develop pulmonary hypertension (PH-COPD). Severe PH-COPD, identified by a pulmonary vascular resistance (PVR) >5 Wood Units (WU), is closely linked to impaired transplant-free survival. The impact of PH-targeting pharmacotherapy in this context remains unclear. Research QuestionIs PH-targeted therapy associated with improved transplant-free survival in PH-COPD? Study Design and MethodsThis study included PVRI GoDeep meta-registry patients with PH-COPD and available right heart catheterization at diagnosis. We investigated PH-targeted therapy prevalence and its association with transplant-free survival using diverse statistical methods, including Cox regression and subgroup analyses based on PH severity, comorbidities, and pulmonary function tests. Immortal time bias was addressed through a landmark approach. ResultsAs of December 2023, the GoDeep meta-registry included 26981 patients (28% PH-Group 1, 13% PH-Group 2, 12% PH-Group 3, 10% PH-Group 4, 2% PH-Group 5, 26% undefined and 9% control). Out of these, 836 patients were diagnosed as PH-COPD and included in this analysis, with median age 66 [59,73]years, FEV1 51 [34,69]%predicted, mPAP 35 [28,44]mmHg, PVR 5 [4,8]WU, cardiac index 2.5 [2.0,2.9]L/min.m2, and mostly WHO functional class III were included. 5-year transplant-free survival was 42%, significantly worse than group 1 PH. A multivariable Cox proportional hazards model identified PVR, but not FEV1 as a major predictor of outcome. 418 patients (50%) received phosphodiesterase-5 inhibitor (PDE5i) therapy, which was associated with significantly reduced mortality: hazard ratio 0.65 [0.57,0.75] for the entire PH-COPD cohort and 0.83 [0.74,0.94] when performing landmark analysis. This PDE5i effect was robustly reproduced when performing subgroup analyses for patients with moderate/severe PH, various comorbidities, and supplemental oxygen requirement, and when assessing the impact of unobserved confounders. InterpretationPH-COPD patients exhibit poor transplant-free survival, with PVR being a predictor of mortality. In this meta-registry, PDE5i therapy was associated with a significant reduction in mortality across all tested models.

The data poverty trap: A moral and statistical dilemma

Key digested messageThis article explores the issue of data poverty and its impact on educational inequality with specific reference to vocational training. It highlights how a lack of comprehensive data affects support services and student outcomes, contributing to survivorship bias. In this specific case, survivorship bias arises because in-depth data is primarily collected from students who were admitted to colleges, neglecting those who were not. This selective data collection misrepresents the needs and barriers of the broader applicant pool. The article also discusses the potential and limitations of artificial intelligence in addressing these challenges, emphasising the need for context-specific data to improve enrolment and support for all students.

785. MANAGEMENT OF ESOPHAGEAL CANCER WITH CONCURRENT CERVICAL NODE METASTASIS: A NATIONWIDE POPULATION-BASED COHORT STUDY

Abstract Background In the Netherlands, the standard treatment of locally advanced, resectable esophageal cancer without metastasis is neoadjuvant chemoradiotherapy followed by esophagectomy. There is a small subset of patients that present with concurrent cervical lymph node metastasis (LNM). Historically this was seen as distant metastasis and surgical intervention has usually not been an option for these patients. The contemporary TNM classification now categorizes these lymph node stations as locoregional disease. Our current study aims to describe current treatment paradigms in the Netherlands for patients presenting with esophageal cancer and concurrent cervical LNM. Methods This population-based cohort study utilized data from the Netherlands Cancer Registry (NCR), encompassing patients with locally advanced thoracic esophageal or gastroesophageal junction cancer and concurrent cervical lymph node metastasis. Treatment modalities were categorized into five options: neoadjuvant therapy followed by surgery (Neo + S), definitive chemoradiotherapy (dCRT), chemotherapy with or without radiotherapy &amp;lt; 30 Gray (CT), radiotherapy (RT), and best supportive care (BSC). Overall survival (OS) was assessed using the Kaplan-Meier method and compared via the log-rank test. Hazard rates were computed using Cox proportional hazards regression, with adjustment for confounding achieved through inverse probability of treatment weighting (IPTW). Results Between 2015 and 2021, a cohort of 412 patients was identified from the NCR database. Median survival durations were observed as follows: 24.2 months for Neo + S, 18.0 months for dCRT, 14.5 months for CT, 7.0 months for RT, and 3.2 months for BSC (Figure). A comparison between the Neo + S group and dCRT demonstrated a significant improvement in survival (p=0.02). Further subdivision of the surgical group into neoadjuvant CRT or chemotherapy did not reveal a significant difference in survival (p=0.6). Utilizing IPTW to adjust for confounding factors, Neo + S maintained its survival advantage. Conclusion The retrospective cohort findings suggest that neoadjuvant therapy followed by surgery may represent the optimal approach for managing esophageal cancer patients with cervical LNMs Yet, it's vital to recognize the influence of confounding by indication, which statistical adjustments may not entirely rectify. Furthermore, immortal time bias notably skews results favorably toward surgery. Nevertheless, the results emphasize the importance of considering surgery as a viable option for these patients. These limitations underscore the critical need for a prospective study, prompting the launch of the NODE-II trial.

An Emulated Target Trial Case Study of Real-World Overall Survival With Second-Line Maintenance Niraparib Versus Active Surveillance in Patients With Recurrent Ovarian Cancer.

This retrospective real-world study compared overall survival (OS) between patients with BRCA wild-type (BRCAwt) recurrent epithelial ovarian cancer (OC) who received niraparib second-line maintenance (2LM) versus active surveillance (AS) using target trial emulation, cloning, inverse probability of censoring weighting (IPCW) methodology to minimize immortal time bias. Eligible patients from a United States-based, deidentified, electronic health record-derived database were diagnosed with epithelial OC (January 1, 2011-May 31, 2021), were BRCAwt, and completed second-line (2L) therapy (January 1, 2017-March 2, 2022). Patient data were cloned at index (2L last treatment date), assigned to niraparib 2LM and AS cohorts, and censored when treatment deviated from clone assignment. Follow-up was measured from index to earliest of study end (May 31, 2022), last activity, or death. Median OS (mOS) and hazard ratios were estimated from stabilized IPCW Kaplan-Meier curves and Cox regression models. Overall, 199 patients received niraparib 2LM, and 707 had their care managed with AS. Key characteristics were balanced across cohorts after cloning and stabilized IPCW. Median follow-up was 15.6- and 9.3-months pre-cloning. IPCW mOS was 24.1 months (95% CI: 20.9-29.5) and 18.4 months (95% CI: 15.1-22.8) in niraparib 2LM and AS cohorts, respectively (hazard ratio, 0.77; 95% CI: 0.66-0.89). This real-world study provides supportive evidence of an OS benefit for patients with BRCAwt recurrent OC who received 2LM niraparib monotherapy compared with those whose care was managed with AS. The analytic strategies implemented were useful in minimizing immortal time bias and measured confounding.

Do corticosteroids affect immunotherapy efficacy in malignancy? - A systematic review.

Early studies indicated that corticosteroids may limit the survival benefit from immunotherapy. We conducted this systematic review to evaluate the effect corticosteroids have on immunotherapy in patients with malignancy, when adjusted for potentially confounding effects of corticosteroids given for palliative indications. Three electronic databases (PubMed, Embase and Medline) were searched on 1 February 2023. Studies that measured response or survival to immunotherapy in people receiving corticosteroids for non-cancer indications compared to either no corticosteroids or corticosteroids for cancer-related indications were included. Studies exclusively evaluating the effect of corticosteroids administered for immune-related adverse events (irAE) were excluded to avoid immortal time bias. Pooled odds and hazard ratios with 95% confidence intervals (CI) were calculated using a random effects model. Study heterogeneity was assessed using the I2 statistic, and publication bias was evaluated by funnel plot and Egger's regression model. Eight thousand four hundred and twenty-six titles were identified on our search. Eight studies met our inclusion criteria for meta-analysis. Administration of corticosteroids does not have a statistically significant effect on survival and response to immunotherapy when administered for non-cancer-related indications, with a pooled odds ratio for overall response rate 1.01 (95% CI 0.64-1.60); pooled hazard ratio (HR) for progression free survival 0.87 (95% CI 0.68-1.12); and pooled HR for overall survival 0.79 (95% CI 0.59-1.05). This systematic review indicates that administration of corticosteroids does not affect response to immunotherapy nor survival outcomes, when removing confounding palliative corticosteroid indications. These results are limited by the retrospective nature of the studies included, small sample sizes, lack of information about corticosteroid dosing and the inclusion of irAE in two of the studies which could bias the results.

Too good to be true: Are GLP-1 receptor agonists the new metformin?

Recently, a health-care database study showed that persons with type 2 diabetes taking GLP-1 receptor agonists (GLP-1 RA) had a significantly lower risk of 10 out of 13 obesity-related cancers than patients taking insulin (Wang L, et al. JAMA Netw Open. 2024 7: e2421305). For some cancers, hazard ratios <0.5 were reported. This is reminiscent of studies published >10 years ago showing that people with type 2 diabetes taking metformin had a lower risk of many types of cancer than those not taking metformin. In some studies, also risk reductions of >50 % were reported.The strong effects observed in the metformin studies were explained by time-related biases, in particular, immortal time bias. In the current GLP-1 RA study, it was striking that the curves for the cumulative incidence of several cancers in GLP-1 RA and insulin users diverged immediately after therapy onset. This indicates that there is most likely a time-related bias: insulin is given at much later stages of type 2 diabetes than GLP-1 RA.The current study suggests that one should be sceptical about database results when spectacular risk reductions are reported. Time-related bias should always be considered as an alternative explanation.

US Real-World Effectiveness Study of Nirmatrelvir/Ritonavir in Preventing Hospitalization of High-Risk COVID-19 Patients

PurposeWe describe nirmatrelvir/ritonavir (NMV/r) effectiveness in preventing hospitalization among COVID-19 patients at high risk of severe disease. MethodsAn ongoing US population-based observational cohort study with retrospective and prospective collection of national electronic healthcare data collected from the US Optum® deidentified COVID-19 Electronic Health Record dataset during December 22, 2021−July 20, 2022. Participants were ≥12 years old; had a positive SARS-CoV-2 test, COVID-19 diagnosis, or NMV/r prescription; and were at high risk of severe COVID-19 based on demographic/clinical characteristics. Potential confounders between groups were balanced using propensity score matching. Immortal time bias was addressed. Hospitalization rates within 30 days from COVID-19 diagnosis were evaluated. Sensitivity analyses included 15-day hospitalization, chart review to investigate incidental hospitalization effects, and exclusion of patients identified as having COVID-19 based on NMV/r prescription alone. Outcomes were also evaluated by race, age, and COVID-19 vaccine status. FindingsOverall, 12,440 and 234,123 patients were included in the NMV/r and non-NMV/r groups, respectively. After propensity score matching, baseline characteristics were well balanced across groups (NMV/r, n = 12,439; non-NMV/r, n = 36,490). Incidence of hospitalization (95% CI) within 30 days was 0.90% (0.74%−1.08%) for the NMV/r group and 5.91% (5.67%−6.16%) for the non-NMV/r group, with relative risk (95% CI) of 0.15 (0.13−0.18; 85% risk reduction). NMV/r was comparably effective in Black patients (relative risk, 0.19 [0.10−0.34]; 81% risk reduction). Sensitivity analyses supported the main outcomes. ImplicationsReal-world NMV/r effectiveness against hospitalization during Omicron predominance among COVID-19 patients at high risk of severe disease supports demonstrated clinical trial efficacy. Black patients underutilized NMV/r despite high effectiveness.

A Bayesian Approach to Survivorship Bias in Historical Data Analysis

A Bayesian Approach to Survivorship Bias in Historical Data Analysis

Overcoming survival bias in targeting mineral deposits of the future: Towards null and negative tests of the exploration search space, accounting for lack of visibility

Broad consensus exists amongst mineral explorers that most outcropping mineral deposits have been found. The next generation of discoveries will rely on our ability to recognize the subtle or cryptic signals of deep-seated deposits. Exploration targeting under such conditions requires greater knowledge of the processes that formed the targeted mineral deposit types and new or improved exploration methods designed to effectively test for buried mineralization. Survival bias is a form of selection bias that is defined as the logical error resulting from neglecting data or information because of their “lack of visibility”. In this study, “lack of visibility” refers to situations where (i) mineral explorers ignore or overlook particular terrain because it lacks or contains only weak signals of a mineralizing system, and (ii) such areas are excluded from further exploration as the existing data or information neither confirm nor support the targeting model. Therefore, it is critical to more comprehensively analyze a search space to more confidentially determine whether a terrain without the desired targeting signals satisfies the criteria of a null or negative test. The idea for this study is based on the notion that if a buried mineral deposit was present in an overlooked terrain it would nevertheless comprise distinctive geological features and targeting signals to guide the explorer, although, more likely than not, these signals would be very weak. Here we used a porphyry copper (Cu) district in Iran to explain and illustrate the adaptation of the survival bias concept. More specifically, in this study we tested the usefulness of a recently proposed targeting criterion, namely sites of potential focused fluid flux, as an input to mineral prospectivity analysis and exploration targeting. The findings of our study have implications for the future development of regional- to global-scale exploration information systems (EIS), designed to improve the performance of mineral exploration targeting.

1-year health outcomes associated with systemic corticosteroids for COVID-19: a longitudinal cohort study.

In patients with coronavirus disease 2019 (COVID-19) requiring supplemental oxygen, dexamethasone reduces acute severity and improves survival, but longer-term effects are unknown. We hypothesised that systemic corticosteroid administration during acute COVID-19 would be associated with improved health-related quality of life (HRQoL) 1 year after discharge. Adults admitted to hospital between February 2020 and March 2021 for COVID-19 and meeting current guideline recommendations for dexamethasone treatment were included using two prospective UK cohort studies (Post-hospitalisation COVID-19 and the International Severe Acute Respiratory and emerging Infection Consortium). HRQoL, assessed by the EuroQol-Five Dimensions-Five Levels utility index (EQ-5D-5L UI), pre-hospital and 1 year after discharge were compared between those receiving corticosteroids or not after propensity weighting for treatment. Secondary outcomes included patient-reported recovery, physical and mental health status, and measures of organ impairment. Sensitivity analyses were undertaken to account for survival and selection bias. Of the 1888 participants included in the primary analysis, 1149 received corticosteroids. There was no between-group difference in EQ-5D-5L UI at 1 year (mean difference 0.004, 95% CI -0.026-0.034). A similar reduction in EQ-5D-5L UI was seen at 1 year between corticosteroid exposed and nonexposed groups (mean±sd change -0.12±0.22 versus -0.11±0.22). Overall, there were no differences in secondary outcome measures. After sensitivity analyses modelled using a cohort of 109 318 patients admitted to hospital with COVID-19, EQ-5D-5L UI at 1 year remained similar between the two groups. Systemic corticosteroids for acute COVID-19 have no impact on the large reduction in HRQoL 1 year after hospital discharge. Treatments to address the persistent reduction in HRQoL are urgently needed.

Inverse Probability Weighting to Estimate Impacts of Hypothetical Occupational Limits on Radon Exposure to Reduce Lung Cancer.

Radon is a known cause of lung cancer. Protective standards for radon exposure are derived largely from studies of working populations that are prone to healthy worker survivor bias. This bias can lead to under-protection of workers and is a key barrier to understanding health effects of many exposures. We apply inverse probability weighting to study a set of hypothetical exposure limits among 4,137 male, White and American Indian radon-exposed uranium miners in the Colorado Plateau followed from 1950 to 2005. We estimate cumulative risk of lung cancer through age 90 under hypothetical occupational limits. We estimate that earlier implementation of the current US Mining Safety and Health Administration annual standard of 4 working level months (implemented here as a monthly exposure limit) could have reduced lung cancer mortality from 16/100 workers to 6/100 workers (95% confidence intervals: 3/100, 8/100), in contrast with previous estimates of 10/100 workers. Our estimate is similar to that among contemporaneous occupational cohorts. Inverse probability weighting is a simple and computationally efficient way address healthy worker survivor bias in order to contrast health effects of exposure limits and estimate the number of excess health outcomes under exposure limits at work.

Positive and negative controls in rheumatology research.

Observational research from large population databases may be affected by unmeasured confounding and time-related biases, such as immortal time bias. Modern causal inference practice applies propensity score-based methods, new-user designs, and other strategies to mitigate bias. The degree to which these methodologic approaches adequately address bias for any particular study may be difficult to measure. Recently, the incorporation of positive and negative controls has been identified as a means to assess for the impacts of residual confounding and/or time-related biases. The objective of this commentary is to describe the role of positive and negative controls in observational research. We offer recommendations for incorporating controls into critical appraisal and observational research projects.

Decreased Long-Term Survival of Patients With Newly Diagnosed Cancer Discharged Home After Unplanned ICU Admission: A Prospective Observational Study.

To compare the 18-month survival between patients with newly diagnosed cancer discharged home after early unplanned ICU admission and those without early unplanned ICU admission; we also evaluated the frequency and risk factors for early unplanned ICU admission. Observational study with prospectively collected data from September 2019 to June 2021 and 18 months follow-up. Single dedicated cancer center in São Paulo, Brazil. We screened consecutive adults with suspected cancer and included those with histologically proven cancer from among 20 highly prevalent cancers. None. The exposure was early unplanned ICU admission, defined as admission for medical reasons or urgent surgery during the first 6 months after cancer diagnosis. The main outcome was 18-month survival after cancer diagnosis, and the main analysis was Cox's proportional hazards model adjusted for confounders and immortal time bias. Propensity score matching was used in the sensitivity analysis. We screened 4738 consecutive adults with suspected cancer and included 3348 patients. Three hundred twelve (9.3%) had early unplanned ICU admission, which was associated with decreased 18-month survival both in the unadjusted (hazard ratio, 4.03; 95% CI, 2.89-5.62) and adjusted (hazard ratio, 1.84; 95% CI, 1.29-2.64) models. The sensitivity analysis confirmed the results because the groups were balanced after matching, and the 18-month survival of patients with early ICU admission was lower compared with patients without early ICU admission (87.0% vs. 93.9%; p = 0.01 log-rank test). Risk factors for early unplanned ICU admission were advanced age, comorbidities, worse performance status, socioeconomic deprivation, metastatic tumors, and hematologic malignancies. Patients with newly diagnosed cancer discharged home after early unplanned ICU admission have decreased 18-month survival compared with patients without early unplanned ICU admission.

Injurious Fall Risk Differences Among Older Adults With First-Line Depression Treatments

One-third of older adults in the US have depression, often treated with psychotherapy and antidepressants. Previous studies suggesting an increased risk of falls and related injuries (FRI) associated with antidepressant use may be affected by confounding by indication or immortal time bias. To evaluate the association between FRI risk and first-line treatments in older adults with depression. This cohort study used a target trial emulation framework with a cloning-censoring-weighting approach with Medicare claims data from 2016 to 2019. Participants included fee-for-service beneficiaries aged 65 years or older with newly diagnosed depression. Data were analyzed from October 1, 2023, to March 31, 2024. First-line depression treatments including psychotherapy, sertraline, escitalopram, citalopram, mirtazapine, duloxetine, trazodone, fluoxetine, bupropion, paroxetine, and venlafaxine. One-year FRI rate, restricted mean survival time (RMST), and adjusted hazard ratio (aHR) with 95% CI. Among 101 953 eligible beneficiaries (mean [SD] age, 76 [8] years), 63 344 (62.1%) were female, 7404 (7.3%) were Black individuals, and 81 856 (80.3%) were White individuals. Compared with the untreated group, psychotherapy use was not associated with FRI risk (aHR, 0.94 [95% CI, 0.82-1.17]), while other first-line antidepressants were associated with a decreased FRI risk (aHR ranged from 0.74 [95% CI, 0.59-0.89] for bupropion to 0.83 [95% CI, 0.67-0.98] for escitalopram). The FRI incidence ranged from 63 (95% CI, 53-75) per 1000 person-year for those treated with bupropion to 87 (95% CI, 83-90) per 1000 person-year for those who were untreated. The RMST ranged from 349 (95% CI, 346-350) days for those who were untreated to 353 (95% CI, 350-356) days for those treated with bupropion. In this cohort study of older Medicare beneficiaries with depression, first-line antidepressants were associated with a decreased FRI risk compared with untreated individuals. These findings provide valuable insights into their safety profiles, aiding clinicians in their consideration for treating depression in older adults.

Dementia Incidence in Survivors of Multiple Myeloma: A National Case-Control Study Conducted in Korea (The CAREMM-2106 Study)

BackgroundDementia, a growing global health issue, affects older adults and specific groups like long-term cancer survivors. The link between cancer survival and dementia is debated. Multiple myeloma (MM), a common blood cancer in older adults, is often linked with cognitive issues. This study investigated dementia incidence in long-term MM survivors using Korean national data. MethodsA retrospective case-control study used data from the Korea National Health Insurance Service (KNHIS), covering about 50 million Koreans. Patients diagnosed with MM between 2009 and 2020 formed the case cohort, while the control cohort included matched individuals without MM using propensity-score matching. Analyzing baseline characteristics, comorbidities, and socioeconomic status, the primary outcome was dementia incidence identified via ICD-10 codes. Statistical methods included Kaplan-Meier plots, cause-specific and Fine–Gray subdistribution hazard models, and a 3-year landmark analysis for immortal time bias. ResultsThe study included 33,864 patients, with 16,932 in each cohort. The overall cumulative dementia incidence was lower in the MM cohort compared to controls. However, in the first 3 years, MM patients had a higher dementia risk (HR: 1.711, 95% CI, 1.562-1.874) than controls. After 3 years, the risk significantly decreased (HR: 0.625, 95% CI, 0.560-0.696). Age-specific analysis showed a consistent pattern, particularly among MM patients aged 70-79, where dementia risk increased post-3 years. ConclusionThis study reveals a lower long-term dementia risk in MM survivors compared to non-MM individuals. Further prospective studies are needed to confirm these findings and explore the underlying mechanisms.

Antifibrotics and mortality in idiopathic pulmonary fibrosis: external validity and avoidance of immortal time bias

Background and objectivePooled analyses of previous randomized controlled trials reported that antifibrotics improved survival in patients with idiopathic pulmonary fibrosis (IPF), but the results were only based on short-term outcome data from selected patients who met strict criteria. Observational studies/meta-analyses also suggested that antifibrotics improve survival, but these studies failed to control for immortal time bias that considerably exaggerates drug effects. Therefore, whether antifibrotics truly improve long-term survival in patients with IPF in the real world remains undetermined and requires external validity.MethodsWe used data from the Japanese National Claims Database to estimate the intention-to-treat effect of antifibrotics on mortality. To address immortal time bias, we employed models treating antifibrotic initiation as a time-dependent covariate and target trial emulation (TTE), both incorporating new-user designs for antifibrotics and treating lung transplantation as a competing event.ResultsOf 30,154 patients with IPF, 14,525 received antifibrotics. Multivariate Fine–Gray models with antifibrotic initiation as a time-dependent covariate revealed that compared with no treatment, nintedanib (adjusted hazard ratio [aHR], 0.85; 95% confidence interval [CI], 0.81–0.89) and pirfenidone (aHR, 0.89; 95% CI, 0.86–0.93) were associated with reduced mortality. The TTE model also replicated the associations of nintedanib (aHR, 0.69; 95% CI, 0.65–0.74) and pirfenidone (aHR, 0.81; 95% CI, 0.78–0.85) with reduced mortality. Subgroup analyses confirmed this association regardless of age, sex, and comorbidities, excluding certain subpopulations.ConclusionsThe results of this large-scale real-world analysis support the generalizability of the association between antifibrotics and improved survival in various IPF populations.

An Exploration of Factors Influencing the Passing of Mainland Chinese Students' Study Abroad Applications Based on Logistic Regression Modeling--Example of Applying for Master's Degree in Hong Kong

In order to explore the admission factors of mainland Chinese students applying for master's degree in Hong Kong, the article collected about 240 data by visiting and researching professional study abroad application agencies and students in colleges and universities. It collected undergraduate institution background, major grades, target institution ranking, language scores and undergraduate grades of the applicants and analyzed and explored them based on the logistic regression model. We found that undergraduate institutional rank, undergraduate GPA, target institution rank, and major match were significantly different across admissions outcomes and were able to conclude, that undergraduate institutional rank, GPA, and target institution rank had the most significant effect on admissions outcomes, and that language scores and major match did not significantly affect admissions outcomes. We hypothesize that there may be a survivor bias in the data collected, and that some unquantifiable factors of soft backgrounds such as research competitions, internships, and patents and journals may have an impact on the admissions outcomes. We also provide strategies to improve the success rate of the application.