Category: Statistics

Arch Dis Child Fetal Neonatal Ed. 2023 Dec 6:fetalneonatal-2023-326340. doi: 10.1136/archdischild-2023-326340. Online ahead of print.

ABSTRACT

This paper critically examines ‘kitchen sink regression’, a practice characterised by the manual or automated selection of variables for a multivariable regression model based on p values or model-based information criteria. We highlight the pitfalls of this method, using examples from perinatal/neonatal medicine, and propose more robust alternatives. The concept of directed acyclic graphs (DAGs) is introduced as a tool for describing and analysing causal relationships. We highlight five key issues with ‘kitchen sink regression’: (1) the disregard for the directionality of variable relationships, (2) the lack of a meaningful causal interpretation of effect estimates from these models, (3) the inflated alpha error rate due to multiple testing, (4) the risk of overfitting and model instability and (5) the disregard for content expertise in model building. We advocate for the use of DAGs to guide variable selection for models that aim to examine associations between a putative risk factor and an outcome and emphasise the need for a more thoughtful and informed use of regression models in medical research.

PMID:38071518 | DOI:10.1136/archdischild-2023-326340

Int J Ment Health Nurs. 2023 Dec 10. doi: 10.1111/inm.13275. Online ahead of print.

ABSTRACT

The high prevalence of mental health problems and underutilization of mental health treatment are more severe among the Native Hawaiian and Other Pacific Islander (NHPI) populations and remain misunderstood and understudied. Examining mental health literacy (MHL) – the knowledge and beliefs about mental disorders – aids their recognition, management, or prevention – has been shown to identify barriers to seeking and receiving care. This study aimed to assess the level of MHL in NHPIs and identify associated demographic variables. Data for this cross-sectional study were collected from 298 US NHPIs via an online questionnaire of the Mental Health Literacy Scale (MHLS). The overall mean MHLS score was 121 (SD = 17.3), with statistically significant higher scores in female participants, >31 years old, Tongan, more educated, and with higher income. This study demonstrated that overall MHL is comparable among NHPI compared to the current literature. However, NHPI men ≤30 years old and with lower income had lower MHL, which may be linked to the mental health disparities specific to this population. Current interventions should focus on increasing knowledge of risk factors, causes, self-treatments, and available professional help regarding mental disorders. Efforts to improve the MHL of NHPI should target men ≤30 years with lower income (<$50 000).

PMID:38071505 | DOI:10.1111/inm.13275

ANZ J Surg. 2023 Dec 10. doi: 10.1111/ans.18816. Online ahead of print.

ABSTRACT

BACKGROUND: Of the 40% of breast cancer patients who have a mastectomy as part of their surgical treatment, only approximately 29% have a breast reconstruction. In 2016, Alfred Health established a multidisciplinary surgical clinic with breast and plastic surgeons, aiming to improve interdisciplinary collaboration. This study aimed to assess the provision of breast reconstruction at an Australian tertiary public hospital and examine whether the multidisciplinary surgical clinic have improved our reconstructive service provision.

METHODS: A retrospective cohort study of patients who underwent mastectomy at Alfred Health between October 2011 and September 2021 was conducted. Patients were divided into before and after groups, treated during the 5-year period before and after establishing the multidisciplinary clinic respectively. Demographic data, operative details, histopathology, and treatments were compared.

RESULTS: Over the 10-year period, 423 mastectomies were performed for 351 patients. Of those, 153 patients underwent breast reconstruction, providing an overall reconstruction rate of 43.6%. There was a statistically significant increase in the breast reconstruction rate from 36.5% before to 53.4% after the creation of the multidisciplinary surgical clinic. Patient factors such as age and tumour receptor status did not differ significantly between the groups.

CONCLUSION: The establishment of a surgical multidisciplinary clinic has led to a statistically significant increase in the rate of breast reconstruction from 36.5% to 53.4%, leading to improved healthcare provision for our patients. Factors identified to be associated with increased uptake in the reconstruction service include younger age and node negative disease.

PMID:38071497 | DOI:10.1111/ans.18816

J Biomech Eng. 2023 Dec 9:1-16. doi: 10.1115/1.4064213. Online ahead of print.

ABSTRACT

Many methods to computationally predict red blood cell damage have been introduced, and among these are Lagrangian methods which track the cells along their pathlines. Such methods typically do not explicitly include cell-cell interactions. Due to the high volume fraction of red blood cells in blood, these interactions could impact cell mechanics and thus, the amount of damage caused by the flow. To investigate this question, cell-resolved simulations of red blood cells in shear flow were performed for multiple interacting cells, as well as for single cells in unbounded flow at an effective viscosity. Simulations run without adjusting the bulk viscosity produced larger errors unilaterally and were not considered further for comparison. We show that a periodic box containing at least 8 cells and a spherical harmonic of degree larger than 10 are necessary to produce converged higher-order statistics. The maximum difference between the single-cell and multiple-cell cases in terms of peak strain was 3.7%. To achieve this, one must use the whole blood viscosity and average over multiple cell orientations when adopting a single-cell simulation approach. The differences between the models in terms of average strain was slightly larger (maximum difference of 6.9%). However, given the accuracy of the single-cell approach in predicting the maximum strain, which is useful in hemolysis prediction, and its computational cost that is orders of magnitude less than the multiple-cell approach, one may use it as an affordable cell-resolved approach for hemolysis prediction.

PMID:38071488 | DOI:10.1115/1.4064213

West Afr J Med. 2023 Dec 4;40(12 Suppl 1):S40.

ABSTRACT

BACKGROUND/AIM: Some estimates indicates that by 2021 ending, more people as a share of the vulnerable population in Africa, Nigeria inclusive, have died than elsewhere due to late and inadequate vaccination. With the pandemic phase of high daily deaths formally declared over, COVID-19 deaths before and after vaccination commenced were compared to observe how vaccination impacted COVID-19 deaths.

METHOD: COVID-19 cases, deaths and vaccination rates in World Health Organization databases up to 07 June 2023 and other variables of interest unavailable there but found in other open- sources were all extracted and examined. Case fatality rate (CFR) per 1,000 for the period prior to vaccination (CFR1) and the period after vaccination commenced (CFR2) was computed. Simple statistics were used in data analysis.

RESULTS: Between when the first case was documented and 05 June 2023, Nigeria recorded 3,155 COVID-19 deaths and majority (61.84%) occurred between 19 March 2020 and March 5, 2021 when vaccination commenced. COVID-19 deaths declined to 61.7% of pre-vaccination figure coinciding with vaccination that delivered partial, primary and booster rates of 39.94%, 33.86% and 5.97% respectively. The cumulative COVID-19 deaths by population size was 8.94/106 pre-vaccination while COVID-19 deaths in vaccination era added 5.510/106mortalities to the final mortality figure of 14. 44/106. The calculated CFR1 and CFR2 rebased were 1.24% and 1.04% respectively.

CONCLUSION: More COVID-19 deaths occurred before vaccination commenced than in over two years of ongoing vaccination.

PMID:38071481

Sci Rep. 2023 Dec 9;13(1):21806. doi: 10.1038/s41598-023-49221-y.

ABSTRACT

In March 2020, the world went into lockdown to curb the spread of the novel coronavirus (SARS-CoV-2), with immediate impacts on wildlife across ecosystems. The strict 2-year long lockdown in Grand Cayman provided an unprecedented opportunity to assess how the ‘human confinement experiment’ influenced the community composition of reef fish. Using a suite of multivariate statistics, our findings revealed a stark increase in reef fish biomass during the 2 years of lockdown, especially among herbivores, including parrotfish, with drastic increases in juvenile parrotfishes identified. Additionally, when comparing baseline data of the community from 2018 to the 2 years during lockdown, over a three-fold significant increase in mean reef fish biomass was observed, with a clear shift in community composition. Our findings provide unique insights into the resilience of reef fish communities when local anthropogenic stressors are removed for an unprecedented length of time. Given the functional role of herbivores including parrotfish, our results suggest that reductions in human water-based activities have positive implications for coral reef ecosystems and should be considered in future management strategies.

PMID:38071390 | DOI:10.1038/s41598-023-49221-y

Sci Rep. 2023 Dec 9;13(1):21838. doi: 10.1038/s41598-023-49376-8.

ABSTRACT

Austria started its COVID-19-vaccination program in December 2020 with three different vaccines. As the vaccination program continues, we encountered increased 2-[18F] FDG-activity not only in axillary lymph nodes ipsilateral to the injection site but also in other organs. The aim of this retrospective study is to present results of the metabolic activity of ipsilateral axillary lymph nodes, liver, blood pool, spleen, and bone marrow after three different vaccines. To our knowledge, this is the first study to examine systemic response changes in relation to time after COVID-19 vaccination using three different vaccines. The collected data of 220 eligible vaccinated patients (127 with BioNTech/Pfizer BNT162b2, 61 with Moderna, and 32 with AstraZeneca) examined with 2-[18F] FDG-PET/CT were enrolled. The PET/CT examinations were evaluated from day 1 to day 135 (SD: 23.2, median: 26) after different vaccinations. Seventy-one out of these 220 patients underwent a pre-vaccination 2-[18F] FDG -PET/CT. SUVmax of axillary node(s), and blood pool, liver, spleen, and bone marrow as reference organs were calculated. The ratio of SUVmax activity of axillary lymph node to reference organs was also compared in all patients. The tracer activity dynamics were investigated in three different vaccines. After BioNTech/Pfizer vaccination 2-[18F] FDG activity in axillary lymph nodes shows a steady decrease in all patients. Ten days after vaccination the 2-[18F] FDG uptake was at its highest activity. Seventy days after vaccination, tracer activity is not different from the background activity of 2-[18F] FDG in the axillary region. This result also applies to other two vaccines; however, in the 4th week after Moderna vaccination SUVmax in lymph nodes showed the highest peak of tracer activity. With AstraZeneca the highest activity was at the earlier days. There was no significant statistical difference of SUVmax of lymph nodes or its ratios to other reference organs between three groups of vaccines. SUVmax in lymph nodes was statistically significant lower than SUVmax in the liver, spleen, and bone marrow with p-values of < 0.001, 0.044, and 0.001, respectively. In the group of 71 patients with a pre-vaccination PET/CT examination, the median SUVmax of lymph nodes increased significantly after vaccination from 0.82 (IQR 0.59-1.38) to 1.80 (IQR 1.07-3.89)(p < 0.001). In contrast median tracer activity in the liver decreased from 3.37 (IQR 2.83-3.91) to 3.11 (2.56-3.70) (p = 0.032). There was no significant change of tracer activity after vaccination in other reference regions (mediastinum, spleen, and bone marrow). In this group of 71 patients, there was also no significant difference in tracer activity in different types of vaccines. Local site and ipsilateral axillary lymph node activity in 2-[18F] FDG PET/CT after COVID19-vaccination is suggested in many studies. The main challenge is recognizing the changes in lymph nodes during time after vaccination to minimize false interpretation, foremost in patients with oncological diagnoses. Moreover, different vaccines cause different system metabolic changes. The knowledge of vaccine type, the time interval between vaccination and PET/CT scan is essential, especially in therapy evaluation.

PMID:38071353 | DOI:10.1038/s41598-023-49376-8

BMC Pediatr. 2023 Dec 9;23(1):625. doi: 10.1186/s12887-023-04450-y.

ABSTRACT

Emergent literacy skills are vital for children’s reading and writing development. While touchscreen devices have been linked to enhanced emergent literacy in developed countries, their impact in low- and middle-income countries (LMICs), with limited access to quality apps, is underexplored. Thailand, classified as an upper-middle-income country, presents a unique context with its specific challenges in educational technology, which have not been extensively studied. This study examined the relationship between touchscreen device usage and emergent literacy development in Thai preschool children. Using a cross-sectional design, we analyzed data from 317 Thai children aged 5-6 years, assessing their emergent literacy skills and examining the association with touchscreen device usage through logistic regression analysis. Our findings showed that 79.5% of participants engaged with touchscreen devices, and there was an observed trend suggesting that exclusive tablet users might exhibit enhanced phonological awareness, letter naming, and rapid automatized naming skills. However, these potential improvements did not reach statistical significance when primary caregiver characteristics were taken into account. Our findings highlight the complexity of this relationship and underscore the need for further research to elucidate the potential influences of application quality and screen time engagement on emergent literacy, particularly in LMICs.

PMID:38071329 | DOI:10.1186/s12887-023-04450-y

Blood Cancer J. 2023 Dec 10;13(1):179. doi: 10.1038/s41408-023-00953-0.

ABSTRACT

Primary induction failure (PIF) in acute myeloid leukemia (AML) patients is associated with poor outcome, with allogeneic hematopoietic stem cell transplantation (HCT) being the sole curative therapeutic option. Here, we retrospectively evaluated long-term outcomes of 220 AML patients undergoing allogeneic HCT after PIF who never achieved remission, and identified clinical and molecular risk factors associated with treatment response and ultimate prognosis. In this high-risk population, disease-free survival was 25.2% after 5 years and 18.7% after 10 years, while overall survival rates were 29.8% and 21.6% after 5 and 10 years of HCT, respectively. 10-year non-relapse mortality was 32.5%, and 48.8% of patients showed disease relapse within 10 years after allogeneic HCT. Adverse molecular risk features determined at initial diagnosis, poor performance status at the time of allogeneic HCT, and long diagnosis-to-HCT intervals were associated with unfavorable prognosis. Collectively, our data suggests that immediate allogeneic HCT after PIF offers long-term survival and cure in a substantial subset of cases and that high-risk AML patients who never achieved complete response during induction might benefit from early donor search.

PMID:38071327 | DOI:10.1038/s41408-023-00953-0

BMC Oral Health. 2023 Dec 9;23(1):990. doi: 10.1186/s12903-023-03666-9.

ABSTRACT

OBJECTIVE: There is growing evidence supporting the presence of oral manifestations associated with COVID-19. The study investigates the knowledge of dental undergraduates and recently graduated dentists concerning oral presentations related to COVID-19.

METHODS: A cross-sectional descriptive study in Saudi Arabia comprised 305 individuals, including undergraduate dental students, interns, and freshly graduated dentists. Data were collected using a questionnaire disseminated to approximately 500 subjects via WhatsApp groups and other applications. The questionnaire was tested in a pilot study for validity, edited, and validated by 2 supervisors at the College of Dentistry, Qassim University, Buraydah, Saudi Arabia. The questionnaire consisted of questions regarding sociodemographic attributes, the level of expertise of dental practitioners, and their knowledge and perspectives regarding COVID-19 and the implementation of oral lesions interrelated to it. The data was subjected to analysis through the utilization of descriptive statistics and chi-square tests, employing the statistical software SPSS (version 24).

RESULTS: About 43.9% of subjects stated that COVID-19 causes oral symptoms. Respondents most frequently reported COVID-19-related dry mouth. Oral ulcers, Candida infection, Hyperpigmentation, tongue coating, atrophy, Petechiae, Herpes, white lesions, Gingivitis, and Periodontitis are further symptoms. COVID-19’s oral manifestation was unknown to 41.0% of subjects, and 37.7% of respondents lacked knowledge regarding the most impacted locations of oral manifestations. Oral signs and COVID-19 symptoms are debated and significantly associated with higher educational levels.

CONCLUSION: The dental students and freshly graduated dentists in this study have proper knowledge of COVID-19 and its symptoms. Also, most dental students and newly graduated dentists recognize the potential correlation between COVID-19 and oral manifestations with an average to excellent knowledge of the types and sites commonly affected. The level of awareness was associated with higher educational levels.

PMID:38071326 | DOI:10.1186/s12903-023-03666-9