Category: Statistics

Crisis. 2023 May 17. doi: 10.1027/0227-5910/a000908. Online ahead of print.

ABSTRACT

Abstract Background: Socioeconomic factors such as financial stress and unemployment are known predictors of suicide. However, no large-scale meta-analyses exist. Aims: Determine the suicide risk following unemployment or financial stress. Method: Literature searched through July 31, 2021. Robust meta-analysis and metaregression of the risk of suicide following financial stress (23 studies) or unemployment (43 studies), from 20 nations. Subgroup meta-analyses by sex, age, year, country, and methodology. Results: The suicide risk following financial stress or unemployment was not significantly elevated among those with diagnosed mental illness. In the general population, we found significantly elevated suicide risks for financial stress (RR: 1.742; 95% CI: 1.339, -2.266) and unemployment (RR: 1.874; CI: 1.501, -2.341). However, neither was significant among studies controlling for physical/mental health (perhaps partially due to lower statistical power). We observed no significant differences by sex, age, or by GDP. We observed a higher suicide risk following unemployment in more recent years. Limitations: Publication bias was evident. We could not examine some individual-level characteristics, most notably the severity/duration of unemployment/financial stress. Heterogeneity was high for some meta-analyses. Studies from non-OECD countries are under-represented. Conclusion: After accounting for physical/mental health, financial stress and unemployment weakly associated with suicide, and the associations may be nonsignificant.

PMID:37194640 | DOI:10.1027/0227-5910/a000908

Med Phys. 2023 May 17. doi: 10.1002/mp.16455. Online ahead of print.

ABSTRACT

PURPOSE: To provide the first clinical test case for commissioning of ¹⁹² Ir brachytherapy model-based dose calculation algorithms (MBDCAs) according to the AAPM TG-186 report workflow.

ACQUISITION AND VALIDATION METHODS: A computational patient phantom model was generated from a clinical multi-catheter ¹⁹² Ir HDR breast brachytherapy case. Regions of interest (ROIs) were contoured and digitized on the patient CT images and the model was written to a series of DICOM CT images using MATLAB. The model was imported into two commercial treatment planning systems (TPSs) currently incorporating an MBDCA. Identical treatment plans were prepared using a generic ¹⁹² Ir HDR source and the TG-43-based algorithm of each TPS. This was followed by dose to medium in medium calculations using the MBDCA option of each TPS. Monte Carlo (MC) simulation was performed in the model using three different codes and information parsed from the treatment plan exported in DICOM radiation therapy (RT) format. Results were found to agree within statistical uncertainty and the dataset with the lowest uncertainty was assigned as the reference MC dose distribution.

DATA FORMAT AND USAGE NOTES: The dataset is available online at http://irochouston.mdanderson.org/rpc/BrachySeeds/BrachySeeds/index.html,https://doi.org/10.52519/00005. Files include the treatment plan for each TPS in DICOM RT format, reference MC dose data in RT Dose format, as well as a guide for database users and all files necessary to repeat the MC simulations.

POTENTIAL APPLICATIONS: The dataset facilitates the commissioning of brachytherapy MBDCAs using TPS embedded tools and establishes a methodology for the development of future clinical test cases. It is also useful to non-MBDCA adopters for intercomparing MBDCAs and exploring their benefits and limitations, as well as to brachytherapy researchers in need of a dosimetric and/or a DICOM RT information parsing benchmark. Limitations include specificity in terms of radionuclide, source model, clinical scenario, and MBDCA version used for its preparation.

PMID:37194638 | DOI:10.1002/mp.16455

Int J Lab Hematol. 2023 May 17. doi: 10.1111/ijlh.14090. Online ahead of print.

ABSTRACT

INTRODUCTION: The objective of the present study was to evaluate and compare the validity and utility of two fully automated ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) activity assays for clinical diagnostic decision-making and to compare their performance.

METHODS: Two automated ADAMTS13 activity assays (Werfen HemosIL® AcuStar ADAMTS13 Activity, Technoclone Technofluor ADAMTS13 Activity) were compared with a manual FRET assay (BioMedica ACTIFLUOR ADAMTS13 Activity). The following samples were used: 13 acute phase TTP (thrombotic thrombocytopenic purpura) samples from 11 different patients, one sample from a patient with congenital ADAMTS13 deficiency, 16 samples from control patients, three follow-up samples from TTP patients in long-term remission and one sample from a patient with stem cell transplantation related thrombotic microangiopathy (TMA). The WHO 1st International Standard for ADAMTS13 and several dilutions of normal plasma with ADAMTS13-depleted normal plasma were also tested. Statistical analysis included descriptive statistics, sensitivity and specificity, Passing & Bablok regression and Bland-Altman plot.

RESULTS: The quantitative comparison between the HemosIL® (x) and Technofluor (y) methods showed a strong correlation (Pearson r = 0.98, n = 49). When considering an ADAMTS13 activity of <10% as a hallmark for the diagnosis of TTP, two fully automated assays were both able to identify all TTP- and non-TTP-samples correctly, resulting in sensitivities and specificities of 100%.

CONCLUSION: Both fully automated ADAMTS13 activity assays showed a good diagnostic performance and quantitative correlation among themselves, discriminating reliably between TTP- and non-TTP-patients.

PMID:37194625 | DOI:10.1111/ijlh.14090

Pediatr Blood Cancer. 2023 May 17:e30413. doi: 10.1002/pbc.30413. Online ahead of print.

ABSTRACT

Rhabdomyosarcoma (RMS) is a well-described cancer in Li-Fraumeni syndrome, resulting from germline TP53 pathogenic variants (PVs). RMS exhibiting anaplasia (anRMS) are associated with a high rate of germline TP53 PVs. This study provides updated estimates of the prevalence of TP53 germline PVs in RMS (3%) and anRMS (11%) from a large cohort (n = 239) enrolled in five Children’s Oncology Group (COG) clinical trials. Although the prevalence of germline TP53 PVs in patients with anRMS in this series is much lower than previously reported, this prevalence remains elevated. Germline evaluation for TP53 PVs should be strongly considered in patients with anRMS.

PMID:37194615 | DOI:10.1002/pbc.30413

J Rehabil Med. 2023 May 17;55:jrm00390. doi: 10.2340/jrm.v55.4529.

ABSTRACT

OBJECTIVE: To appraise research evidence on the effects of balance training on balance and fall efficacy in patients with osteoporosis.

METHODS: Six electronic databases were searched from inception of the database to 1 August 2022, with no language restrictions, and randomized controlled trials of balance training in patients with osteoporosis were included in this meta-analysis. Two authors independently screened and reviewed the articles and assessed the methodological quality using the Cochrane risk-of-bias tools. Trial sequential analysis was conducted.

RESULTS: A total of 10 randomized controlled trials with 684 patients were included. Three of the studies that were included had low risk of bias, 5 had moderate risk of bias, and 2 had high risk of bias. A meta-analysis demonstrated that balance training improves dynamic balance measured using the Timed Up and Go Test (mean difference (MD) = -1.86, 95% CI (-2.69, -1.02), Z = 4.38, p < 0.0001) and the Berg Balance Scale (MD = 5.31, 95% CI (0.65, 9.96), Z = 2.23, p < 0.03), static balance measured using One-Leg Standing Time (MD = 4.10, 95% CI (2.19, 6.01), Z = 4.21, p < 0.0001), and fall efficacy measured using the Falls Efficacy Scale International (MD = -4.60, 95% CI (-6.33, -2.87), Z = 5.20, p < 0.00001) were also significantly improved. Trial sequential analysis showed reliable evidence of the effects of balance training on dynamic and static balance improvement. The conclusions of this review are supported by the statistical and clinical significance of all outcomes in the meta-analysis, based on the advised minimal clinically significant differences and minimum detectable changes.

CONCLUSION: Balance training may be effective in improving balance ability and reducing fear of falling in patients with osteoporosis.

PMID:37194565 | DOI:10.2340/jrm.v55.4529

Paediatr Perinat Epidemiol. 2023 May 17. doi: 10.1111/ppe.12984. Online ahead of print.

ABSTRACT

BACKGROUND: The effectiveness of fetal echocardiography in reducing the mortality from congenital heart disease (CHD) is largely unknown.

OBJECTIVES: This study aimed to evaluate whether the widespread use of fetal echocardiography owing to the initiation of insurance coverage in Japan was associated with a decreasing trend in the annual number of CHD-related deaths.

METHODS: Data regarding the number of deaths from CHD in infants aged <12 months were extracted from Japanese demographic statistics (2000-2018). Segmented regression analysis was performed on the interrupted time series data by stratifying the sample into CHD subgroups based on ICD-10 classification and sex.

RESULTS: After the initiation of insurance coverage for fetal echocardiography in 2010, a decrease was observed in the trends of annual deaths in patients with congenital malformations of aortic and mitral valves (ratio of trends before and after the initiation of insurance coverage for fetal echocardiography 0.96, 95% confidence interval 0.93, 0.99). In this group, the decrease persisted after adjusting for annual total infant deaths and cardiac surgery mortality and in the analysis of trends in the proportion of deaths in this group per total CHD deaths. However, a decrease in trends was not observed in other patient groups with CHD. In the sex-stratified analysis, a decrease was noted only in male patients with congenital malformations of aortic and mitral valves.

CONCLUSIONS: The nationwide trend in annual CHD deaths decreased after the initiation of insurance coverage for fetal echocardiography only among patients with congenital malformation of aortic and mitral valves. These findings suggest that prenatal diagnosis with fetal echocardiography has led to improved mortality outcomes among these patients in Japan.

PMID:37194557 | DOI:10.1111/ppe.12984

Ophthalmic Physiol Opt. 2023 May 17. doi: 10.1111/opo.13164. Online ahead of print.

ABSTRACT

PURPOSE: The purpose of this study was to assess accommodative function in non-presbyopic individuals diagnosed with type 1 diabetes (T1D) without any signs of retinopathy, to determine the existence of possible accommodative disorders related to this disease, and to determine the influence of T1D duration and glycosylated haemoglobin values on accommodative function.

METHODS: This comparative, cross-sectional study included 60 participants between 11 and 39 years old, 30 with T1D and 30 controls, with no previous eye surgery, ocular disease or medication that could affect the results of the visual examination. Amplitude of accommodation (AA), negative and positive relative accommodation (NRA and PRA), accommodative response (AR) and accommodative facility (AF) were assessed using the tests that showed the highest repeatability. Participants were classified based on normative values into ‘insufficiency, excess or normal results’, and a diagnosis of accommodative disorders (accommodative insufficiency, accommodative infacility and accommodative excess) was made.

RESULTS: Participants with T1D had statistically significant lower AA and AF and higher NRA values than the controls. Furthermore, AA was significantly and inversely correlated with age and the duration of diabetes; however, AF and NRA were only correlated with disease duration. In the classification by accommodative variables, a higher percentage of ‘insufficiency values’ was observed in the T1D group (50%) than in the control group (6%; p < 0.001). In terms of accommodative disorders, accommodative infacility was the most prevalent (15%), followed by accommodative insufficiency (10%).

CONCLUSIONS: Our findings indicate that T1D affects most accommodative parameters, with accommodative insufficiency being associated with this disease.

PMID:37194554 | DOI:10.1111/opo.13164

Stat Methods Med Res. 2023 May 17:9622802231173491. doi: 10.1177/09622802231173491. Online ahead of print.

ABSTRACT

The goal of causal mediation analysis, often described within the potential outcomes framework, is to decompose the effect of an exposure on an outcome of interest along different causal pathways. Using the assumption of sequential ignorability to attain non-parametric identification, Imai et al. (2010) proposed a flexible approach to measuring mediation effects, focusing on parametric and semiparametric normal/Bernoulli models for the outcome and mediator. Less attention has been paid to the case where the outcome and/or mediator model are mixed-scale, ordinal, or otherwise fall outside the normal/Bernoulli setting. We develop a simple, but flexible, parametric modeling framework to accommodate the common situation where the responses are mixed continuous and binary, and, apply it to a zero-one inflated beta model for the outcome and mediator. Applying our proposed methods to the publicly-available JOBS II dataset, we (i) argue for the need for non-normal models, (ii) show how to estimate both average and quantile mediation effects for boundary-censored data, and (iii) show how to conduct a meaningful sensitivity analysis by introducing unidentified, scientifically meaningful, sensitivity parameters.

PMID:37194551 | DOI:10.1177/09622802231173491

Bull Entomol Res. 2023 May 17:1-12. doi: 10.1017/S0007485323000159. Online ahead of print.

ABSTRACT

Between 1990 and 1999, at Rekomitjie Research Station, Zambezi Valley, Zimbabwe, 29,360 female G. pallidipes were dissected to determine their ovarian category and trypanosome infection status. Overall prevalences were 3.45 and 2.66% for T. vivax and T. congolense, respectively, declining during each year as temperatures increased from July – December. Fits to age-prevalence data using Susceptible-Exposed-Infective (SEI) and SI compartmental models were statistically better than those obtained using a published catalytic model, which made the unrealistic assumption that no female tsetse survived more than seven ovulations. The improved models require knowledge of fly mortality, estimated separately from ovarian category distributions. Infection rates were not significantly higher for T. vivax than for T. congolense. For T. congolense in field-sampled female G. pallidipes, we found no statistical support for a model where the force of infection was higher at the first feed than subsequently. The long survival of adult female tsetse, combined with feeding at intervals ≤3 days, ensures that post-teneral feeds, rather than the first feed, play the dominant role in the epidemiology of T. congolense infections in G. pallidipes. This is supported by estimates that only about 3% of wild hosts at Rekomitjie were harbouring sufficient T. congolense to ensure that tsetse feeding off them take an infected meal, so that the probability of ingesting an infected meal is low at every meal.

PMID:37194504 | DOI:10.1017/S0007485323000159

Stat Med. 2023 May 30;42(12):1909-1930. doi: 10.1002/sim.9704. Epub 2023 Mar 7.

ABSTRACT

In this article, we propose a two-level copula joint model to analyze clinical data with multiple disparate continuous longitudinal outcomes and multiple event-times in the presence of competing risks. At the first level, we use a copula to model the dependence between competing latent event-times, in the process constructing the submodel for the observed event-time, and employ the Gaussian copula to construct the submodel for the longitudinal outcomes that accounts for their conditional dependence; these submodels are glued together at the second level via the Gaussian copula to construct a joint model that incorporates conditional dependence between the observed event-time and the longitudinal outcomes. To have the flexibility to accommodate skewed data and examine possibly different covariate effects on quantiles of a non-Gaussian outcome, we propose linear quantile mixed models for the continuous longitudinal data. We adopt a Bayesian framework for model estimation and inference via Markov Chain Monte Carlo sampling. We examine the performance of the copula joint model through a simulation study and show that our proposed method outperforms the conventional approach assuming conditional independence with smaller biases and better coverage probabilities of the Bayesian credible intervals. Finally, we carry out an analysis of clinical data on renal transplantation for illustration.

PMID:37194500 | DOI:10.1002/sim.9704