Category: Statistics

BMC Oral Health. 2024 Nov 16;24(1):1396. doi: 10.1186/s12903-024-05166-w.

ABSTRACT

BACKGROUND: Dental age estimation is one of the most reliable methods for determining age, commonly used for forensic, criminal, and anthropological purposes. The purpose of this study was to assess and compare the precision of the Bedek models and the Cameriere-European Formula (CF) in determinating dental age in a sample of Turkish individuals.

METHODS: Retrospective panoramic radiographs of 1018 subjects (497 boys and 521 girls) aged 5-14 years were evaluated using the Bedek models and the CF. The differences between calculated dental age (DA) and chronological age (CA) for each sex and age group were analyzed using the paired sample t-test and the Wilcoxon signed-rank test. The accuracy of the methods used to estimate dental age was determined by calculating the mean absolute error (MAE) based on the proximity of the dental age to the chronological age.

RESULTS: The CF method overestimated CA by 0.1 year in the entire sample. Conversely, the Bedek models tended to overestimate CA, with the three-, four-, and seven-tooth models exhibiting the most significant difference. There was a statistically significant difference between boys and girls in the DA-CA calculation using the CF method in the entire sample. Among the Bedek models, the three- and four-tooth models had the lowest MAE in the entire sample, while the single-tooth model had the highest MAE.

CONCLUSION: The CF method showed higher accuracy in predicting the age of children living in eastern Turkey compared to the Bedek Models.

PMID:39550551 | DOI:10.1186/s12903-024-05166-w

BMC Infect Dis. 2024 Nov 16;24(1):1311. doi: 10.1186/s12879-024-10201-w.

ABSTRACT

BACKGROUND: With the continuous advancement of modern medical technology, the survival rate of premature infants has significantly increased. Klebsiella pneumoniae (K. pneumoniae) is one of the most common pathogens causing neonatal infections, particularly posing a serious risk to premature infants. This study aimed to analyze the clinical characteristics, antibiotic susceptibility profiles, and treatment outcomes of K. pneumoniae infections in these infants.

METHODS: We retrospectively compared cases of K. pneumoniae infection in premature and term infants admitted in a tertiary hospital from January 2017 to December 2022 in China. Clinical and microbiological characteristics were evaluated. Data analysis was performed using the Statistical Package for the Social Sciences (SPSS), with statistical significance defined as P < 0.05.

RESULTS: We enrolled 166 premature infants and 68 term infants. In premature infants, fetal distress, patent ductus arteriosus, patent foramen ovale, enteritis, anemia, hypoproteinemia, bloodstream infections, abdominal infection, mechanical ventilation, nasogastric feeding, drainage tube, parenteral nutrition, and prior exposure to carbapenem antibiotics were identified as significant risk factors for K. pneumoniae infections in univariate analysis. Furthermore, septic shock, bloodstream infections, abdominal infections, indwelling catheters, drainage tubes, parenteral nutrition, and previous exposure to glycopeptide antibiotics were significantly correlated with mortality. Independent risk factors for K. pneumoniae infections in premature infants included fetal distress (OR: 3.702, [95% CI: 1.056-12.986], P = 0.041), enteritis (OR: 4.434, [95% CI: 1.066-18.451], P = 0.041), anemia (OR: 4.028, [95% CI: 1.550-10.466], P = 0.004), bloodstream infections (OR: 1.221, [95% CI: 0.061-1.802], P = 0.022), mechanical ventilation (OR: 4.974, [95% CI: 1.685-14.685], P = 0.004) and prior exposure to carbapenem antibiotic (OR: 14.738, [95% CI: 2.393-90.767], P = 0.004). Additionally, abdominal infections (OR: 8.598, [95% CI: 2.000-36.957], P = 0.004) and indwelling catheters (OR: 7.698, [95% CI: 0.998-59.370], P = 0.050) were positive predictors of mortality.

CONCLUSION: K. pneumoniae isolates exhibit a notable prevalence of infection, poor treatment outcomes, and elevated resistance in preterm neonates. These findings enhance our understanding of K. pneumoniae infections and their association with clinical outcomes among premature infants.

PMID:39550549 | DOI:10.1186/s12879-024-10201-w

BMC Oral Health. 2024 Nov 16;24(1):1394. doi: 10.1186/s12903-024-05183-9.

ABSTRACT

BACKGROUND: This study aimed to investigate the in vitro effect of a charcoal-containing dentifrice with different toothbrush stiffness on enamel.

METHODS: Four main groups were applied: distilled water, conventional fluoridated toothpaste (Colgate^® Total^® 12 Clean Mint Toothpaste), charcoal toothpaste (Colgate^® Total^® Charcoal Toothpaste) and whitening toothpaste (Colgate Total^® Advanced Whitening Toothpaste). Three subgroups for each toothpaste were further included according to the toothbrush bristles’ stiffness (soft, medium, and hard). Enamel specimens were subjected to 1,250 and 2,500 cycles of brushing using toothbrushing simulation machine. The average surface roughness change (ΔRa) in nanometer (nm) was measured to estimate the changes following the brushing simulation model. Two-way ANOVA and Tukey tests analyzed the data.

RESULTS: The type of toothpaste and the bristles’ stiffness were determinant factors in increasing the ΔRa value (P = < 0.05). Generally, charcoal and whitening toothpastes with medium and hard bristles yielded higher ΔRa than fluoridated toothpaste and smooth bristles. Following 1,250 cycles of brushing simulation, charcoal toothpaste did not increase the enamel roughness compared to the controls. However, in prolonged brushing via 2,500 cycles of brushing simulation, using bristles with soft stiffness revealed that charcoal toothpaste was associated with increased surface roughness (55.86 ± 41.18 nm), which was statistically significant (P = 0.024) compared to the negative control. Using bristles with medium stiffness showed that the whitening (68.23 ± 48.58 nm) and charcoal (73.62 ± 34.66 nm) toothpastes significantly (P = < 0.05) increased the enamel roughness compared to the conventional toothpaste (36.53 ± 22.56 nm). There was no significant difference among the groups when brushes with hard bristles were used, as all the groups revealed increased enamel roughness.

CONCLUSION: The use of charcoal and whitening toothpastes increased enamel roughness, particularly with long-term use. The effect of bristle stiffness on enamel roughness was found to vary depending on the type of toothpaste used.

PMID:39550548 | DOI:10.1186/s12903-024-05183-9

BMC Genomics. 2024 Nov 15;25(1):1088. doi: 10.1186/s12864-024-10936-5.

ABSTRACT

BACKGROUND: Genomic structural variations (GSVs), notably copy number variations (CNVs), significantly shape genetic diversity and facilitate adaptation in cattle populations. Despite their importance, the genome-wide characterization of CNVs in indigenous Ethiopian cattle breeds-Abigar, Fellata, and Gojjam-Highland remains largely unexplored. In this study, we applied a read-depth approach to whole genome sequencing (WGS) data to conduct the first comprehensive analysis of CNVs in these populations.

RESULTS: We identified 3,893 CNV regions (CNVRs) covering 19.15 Mb (0.71% of the cattle genome). These CNVRs ranged from 1.60 kb to 488.0 kb, with an average size of 4.92 kb. These CNVRs included deletions (1713), duplications (1929), and mixed events (251) showing notable differences in distribution among the breeds. Four out of five randomly selected CNVRs were successfully validated using real time polymerase chain reaction (qPCR). Further analyses identified candidate genes associated with high-altitude adaptation (GBE1 and SOD1), heat stress adaptation (HSPA13, DNAJC18, and DNAJC8) and resistance to tick infestations (BoLA and KRT33A). In addition, variance stabilizing transformation (V_ST) statistics highlighted population-specific CNVRs, emphasizing the unique genetic signatures of high-altitude adaptation in the Gojjam-Highland cattle breed. Among the detected CNVRs, 4.93% (192 out of 3,893) overlapped with 520 quantitative traits loci (QTLs) associated with six economically important trait categories suggesting that these CNVRs may significantly contribute to the genetic variation underlying these traits.

CONCLUSIONS: Our comprehensive analysis reveals significant CNVRs associated with key adaptive traits in Ethiopian cattle breeds highlighting their genetic diversity and resilience. These findings offer valuable insights into the genetic basis of adaptability and can inform sustainable breeding practices and conservation efforts. Future research should prioritize the functional validation of these CNVRs and their integration into breeding programs to enhance traits such as disease resistance and environmental adaptability.

PMID:39548375 | DOI:10.1186/s12864-024-10936-5

BMC Infect Dis. 2024 Nov 15;24(1):1308. doi: 10.1186/s12879-024-10117-5.

ABSTRACT

Serological diagnostic tests are available that measure antibody levels against SARS-CoV-2 antigens. We utilized the Vaxarray Coronavirus (CoV) seroassay, which measures SARS-CoV-2 IgG antibodies against the full-length spike protein (FLS), receptor binding domain (RBD), and S2 extracellular domain (ECD). Previous serological studies have used reference values that have not been validated and require many samples. Here, we show statistically established reference values determined using the upper tail of the Student t-distribution method. The target population was any personnel age 18 years and older working on a U.S. Navy ship, and vaccinated with Wuhan variant. The relative fluorescence mean (RFM) reference values for the full-length spike protein, RBD, and S2 ECD were 17,731, 13,990 and 9096, respectively. By using generalized non-parametric regression and reference values for the RBD spike protein and S2 ECD of SARS-CoV-2, this study was able to distinguish vaccine-mediated immune responses from natural infections. We provide the method and statistical code as a resource to determine future reference values for other serological assays.

PMID:39548371 | DOI:10.1186/s12879-024-10117-5

BMC Med Res Methodol. 2024 Nov 15;24(1):283. doi: 10.1186/s12874-024-02399-9.

ABSTRACT

BACKGROUND: The use of the multistate Markov chain model is a valuable tool for studying child undernutrition. This allows us to examine the trends of children’s transitions from one state to multiple states of undernutrition.

OBJECTIVES: In this study, our objective was to estimate the median duration for a child to first transition from one state of undernutrition to another as well as their first recurrence of undernutrition and also to analyze the typical duration of undernourishment. This involves understanding the central tendency of these transitions and durations in the context of longitudinal data.

METHODS: We used a longitudinal dataset from the Young Lives cohort study (YLCS), which included approximately 1997 Ethiopian children aged 1-15 years. These children were selected from five regions and followed through five survey rounds between 2002 and 2016. The surveys provide comprehensive health and nutrition data and are designed to assess childhood poverty. To analyze this dataset, we employed a Markov chain regression model. The dataset constitutes a cohort with repeated measurements, allowing us to track the transitions of individual children across different states of undernutrition over time.

RESULTS: The findings of our study indicate that 46% of children experienced concurrent underweight, stunting, and wasting (referred to as USW). The prevalence of underweight and stunted concurrent condition (US) was 18.7% at baseline, higher among males. The incidence density of undernutrition was calculated at 22.5% per year. On average, it took 3.02 months for a child in a wasting state to transition back to a normal state for the first time, followed by approximately 3.05 months for stunting and 3.89 months for underweight. It is noteworthy that the median duration of undernourishment among children in the US (underweight and stunted concurrently) state was 48.8 months, whereas those concurrently underweight and wasting experienced a median of 45.4 months in this state. Additionally, rural children (HR = 1.75; 95% CI: 1.53-1.97), those with illiterate fathers (HR = 1.50; 95% CI: 1.38-1.62) and mothers (HR = 1.45; 95% CI: 1.02-3.29), and those in households lacking safe drinking water (HR = 1.70; 95% CI: 1.26-2.14) or access to cooking fuel (HR = 1.95; 95% CI: 1.75-2.17) exhibited a higher risk of undernutrition and a slower recovery rate.

CONCLUSIONS: This study revealed that rural children, especially those with illiterate parents and households lacking safe drinking water but cooking fuels, face an increased risk of undernutrition and slower recovery.

PMID:39548366 | DOI:10.1186/s12874-024-02399-9

BMC Cardiovasc Disord. 2024 Nov 15;24(1):648. doi: 10.1186/s12872-024-04291-2.

ABSTRACT

BACKGROUND: Anemia represents a commonly reported comorbidity in patients diagnosed with heart failure (HF), related with a higher risk of unfavorable outcomes such as recurrent hospitalizations and mortality. There is a lack of evidence in Latin America regarding this topic. Our aim was to evaluate the prognostic value of the diagnosis of anemia in patients from the Colombian Heart Failure Registry (RECOLFACA).

METHODS: RECOLFACA registry included adult ambulatory patients with HF in 60 medical centers in Colombia during 2017-2019. Baseline characteristics of patients diagnosed with anemia and those without anemia were compared. The main outcome was all-cause mortality. A Cox proportional hazards regression model was used to evaluate the factors linked to the main outcome in patients with anemia. A statistically significant p-value was < 0.05.

RESULTS: From the 2528 patients included in RECOLFACA, 2409 had at least one available hemoglobin value, and 726 (30.1%) corresponded to a diagnosis of anemia. Patients with anemia were significantly older, and had a higher prevalence of comorbidities, especially hypertension, type 2 diabetes, and chronic kidney disease (CKD). Patients without anemia had significantly lower mortality rate of 0.30 per 1000 person-years (95% CI 0.26-0.35), compared to patients diagnosed with anemia who had a mortality rate of 0.42 per 1000 person-years (95% CI 0.26-0.98) (p < 0.001). Lastly, the multivariate model results showed that the presence of an anemia diagnosis was associated with a significantly greater risk of mortality (HR 1.48; 95% CI 1.06, 2.05, p < 0.001).

CONCLUSIONS: Anemia represents a highly prevalent comorbidity in patients with HF in Colombia and is also related with higher mortality in ambulatory patients during follow-up period. Our results highlight the relevance of anemia in the pathophysiology of HF. Nevertheless, due to its observational nature, out study results must be validated and further explored in future studies to elucidate the potential underlying mechanisms of this association.

PMID:39548365 | DOI:10.1186/s12872-024-04291-2

BMC Cardiovasc Disord. 2024 Nov 16;24(1):652. doi: 10.1186/s12872-024-04317-9.

ABSTRACT

BACKGROUND: Cardiovascular disease (CVD) is a major global health concern with increasing incident cases and deaths. Homocysteine (Hcy) has been investigated for its potential association with CVD, researchers have debated the extent to which Hcy should be considered a risk factor for cardiovascular diseases, as only 50% of CVD can be explained by classical risk factors.

METHODS: We conducted a prospective cohort study using NHANES 1999-2006 data, analyzing 1,739 US patients aged at least 30 with CVD. Cox proportional hazards regression and restricted cubic splines were used to examine the relationship between Hcy levels and mortality, adjusting for covariates.

RESULT: A total of 1,739 participants with cardiovascular disease (CVD) were enrolled, with a median follow-up period of 126 months. Among them, 1,194 participants died, including 501 deaths due to cardiovascular causes. After adjusting for covariates, the hazard ratios (HR) and 95% confidence intervals (CI) for CVD mortality at different levels of homocysteine (Hcy) (T1 (< 9.3), T2 (9.3-12.5), T3 (> 12.5)) were 1.26 (0.92, 1.73) (T2), and 1.69 (1.14, 2.51) (T3) (P for trend = 0.0086). The HR and 95% CI for all-cause mortality at different levels of Hcy were 1.22 (1.05, 1.42) (T2) and 1.64 (1.29, 2.09) (T3) (P for trend < 0.0001). Elevated Hcy levels were associated with increased risks of all-cause mortality and CVD deaths, even at levels below the conventional threshold. The nonlinear relationship was observed, with inflection points at 14.5 µmol/L for all-cause mortality and 14.6 µmol/L for CVD mortality. Subgroup analyses revealed interactions with age, serum vitamin B12, and smoking.

CONCLUSION: Our study supports the notion that elevated Hcy levels are associated with higher all-cause and CVD mortality risks in CVD participants. The impact of Hcy on health outcomes can be observed at lower concentrations than previously thought.

PMID:39548360 | DOI:10.1186/s12872-024-04317-9

J Dent Educ. 2024 Nov 15. doi: 10.1002/jdd.13785. Online ahead of print.

ABSTRACT

PURPOSE: To compare the educational outcomes of remote instruction (RI) in impression-taking using smart glasses with those of face-to-face instruction (FI) and paper-based self-learning (SL) and analyze the educational effects, aiming to develop a remote clinical training strategy.

METHODS: Participants were recruited from among the dental residents who were trained in the first-year clinical program at the university hospital in 2023. The participants were divided into three groups as the original skill level was equal, and the groups were assigned RI, FI, printed guidance, and SL. All the participants took impressions of the jaw models attached to the mannequin using alginate impression material. Next, assigned instructions were provided. Then again, the trainees took impressions of the jaw models. The pre- and postinstruction impressions of each participant were evaluated, and the change in the impression score was statistically analyzed.

RESULTS: The pre- and postinstruction scores of the trainees in the RI and FI groups showed a significant increase (p < 0.05), whereas no significant difference was observed in the score changes in the SL group. In the intergroup comparisons, the score changes of the RI and FI groups were greater than those of the SL group, although no significant difference was found between the score changes of the RI and FI groups (p < 0.05).

CONCLUSION: RI in impression-taking using smart glasses has a greater educational effectiveness than paper-based SL. It has also been suggested that RI can have educational efficacy similar to FI.

PMID:39548350 | DOI:10.1002/jdd.13785

Sci Rep. 2024 Nov 15;14(1):28176. doi: 10.1038/s41598-024-79999-4.

ABSTRACT

Low fertility is not conducive to healthy population development. The total fertility rate (TFR) is influenced by the education expansion (measured by the proportion of non-student women, NSP), marriage delay (measured by the proportion of married women, MP), and marital fertility rate (MFR). This study decomposes the TFR change into the changes in NSP, MP, and MFR using China’s census and 1% population sample survey data. During 1990-2020, the changes in NSP, MP, and MFR contributed – 22%, – 90%, and 12%, respectively, to the changes in TFR. The continuous decline in NSP reduced the TFR, and the intensity continued to increase over time. As the primary negative driving force, the rapid decline in MP also consistently reduced the TFR. The marital fertility rate had a downward effect on the TFR before 2000 and an upward effect after 2000. The effects of NSP, MP, and MFR on the TFR varied with the birth order, age and region (among cities, towns, and villages). In summary, China’s TFR has considerably changed in combination with changes in NSP, MP, and MFR. Without effective measures, China’s TFR may further decline into the lowest-low fertility trap.

PMID:39548321 | DOI:10.1038/s41598-024-79999-4