Tag: statistics

Folia Morphol (Warsz). 2022 Jul 12. doi: 10.5603/FM.a2022.0066. Online ahead of print.

ABSTRACT

The foramen magnum is the largest opening at the base of the skull. The dimensions of the foramen magnum are of significant clinical importance because of the vital structures that pass through it. The aim of the study was the morphometric analysis of the foramen magnum in children based on head computed tomography. The study was carried out on 84 CTs of the head of children aged 0-18 years; seven age groups were distinguished. The sagittal and transverse dimensions were measured to determine the growth rate, changes between groups, and differences in the foramen size by sex. Statistical analysis of changes was performed. The entire group’s mean transverse and sagittal dimensions were 29.08 mm (SD 3.4 mm) and 35.63 mm (SD 4.23 mm). By sex, the mean transverse dimension in girls was 28.53 mm (SD 3.25 mm), and in boys, 29.6 mm (SD 3.49 mm). The mean sagittal dimension was 35.15 mm (SD 3.76 mm) in girls and 36.09 mm (SD 4.64 mm) in boys. Both dimensions were higher for the male sex. A statistically significant increase in the foramen magnum size was demonstrated up to the age of 36 months in the following age groups; above that age, the increase was statistically insignificant. The dimensions were similar to those described in adults a moderate dependence of the foramen magnum size on age was found.

PMID:35818806 | DOI:10.5603/FM.a2022.0066

Folia Morphol (Warsz). 2022 Jul 12. doi: 10.5603/FM.a2022.0067. Online ahead of print.

ABSTRACT

BACKGROUND: To investigate the anatomical characteristics and symmetry of the bilateral glenoid structures of Chinese people and to explore the relationship between the glenoid bone structure and recurrent anterior dislocation.

MATERIALS AND METHODS: The control group included 131 individuals with no history of shoulder dislocation. The dislocation group consisted of 131 patients with a history of unilateral shoulder dislocation. All subjects underwent CT scans. Glenoid shape (pear-shaped, inverted comma-shaped, oval-shaped), width, height, depth, version angle, area, maximum fitting circle area and volume were measured.

RESULTS: There was no significant difference in normal bilateral glenoid of Chinese people (P > 0.05). There were statistically significant differences in depth, height to width ratio, maximum fitting circle area and shape between the dislocation and control groups (P < 0.05). Regression analyses showed that the glenoid depth (odds ratio 0.48; P < 0.01), the glenoid height to width ratio (odds ratio 28.61; P < 0.01), the glenoid maximum fitting circle area (odds ratio 1.01; P < 0.01) and the glenoid shape (P < 0.05; pear-shaped odds ratio 0.432; inverted comma-shaped odds ratio 0.954) were associated with anterior shoulder instability. Pear-shaped and inverted comma-shaped glenoid had lower risk of recurrent anterior shoulder dislocation compared to oval glenoid. ROC curve analysis showed that individuals with anterior shoulder instability had smaller glenoid depth and larger height to width ratio and the glenoid maximum fitting circle area compared with the control group.

CONCLUSIONS: The normal bilateral glenoids of Chinese people are basically symmetrical. The glenoid shape, depth, height to width ratio and maximum fitting circle area are risk factors for recurrent anterior shoulder dislocation. Evaluation of the glenoid bone structure enables more accurate prediction of the risk of recurrent shoulder dislocation.

PMID:35818805 | DOI:10.5603/FM.a2022.0067

Clin Transplant. 2022 Jul 12:e14771. doi: 10.1111/ctr.14771. Online ahead of print.

ABSTRACT

INTRODUCTION: The presence of median arcuate ligament (MAL) during orthotopic liver transplantation (OLT) may cause a significant reduction of the arterial hepatic flow. The aim of the present study is to investigate the impact of MAL on biliary complications in patients who underwent OLT.

METHODS: We performed a retrospective case-control study among patients who underwent OLT in Geneva University Hospital between 2007 and 2017, depending on the presence or absence of MAL. The matching was performed according to age, gender, lab-MELD score at time of OLT and type of donor (living or dead). The presence of MAL was assessed by an expert liver radiologist on the preoperative CT angiographic evaluation.

RESULTS: The incidence of MAL was 6.1% (19 patients). Baseline characteristics were comparable between the two groups. No significant difference in biliary complications was found between patients with and without MAL (37% and 24% respectively). No patient presented hepatic artery thrombosis. After logistic regression, in patients with MAL, the MAL release and gastroduodenal artery preservation compared to no treatment, showed an odds ratio for post-OLT biliary complications of 1.5 and 1.25 respectively. There was no difference in overall graft survival and in hazard for biliary complications between patients with and without MAL.

CONCLUSION: In the present study, we did not find any difference in the prevalence of biliary and arterial complications between patients with and without MAL. The choice of MAL treatment did not influence in a significant way the overall outcome and development of complications. However, if, at the end of arterial reconstruction, the arterial flow is not adequately established, MAL needs to be treated with the least invasive technique. This article is protected by copyright. All rights reserved.

PMID:35818793 | DOI:10.1111/ctr.14771

Clin Oral Implants Res. 2022 Jul 12. doi: 10.1111/clr.13973. Online ahead of print.

ABSTRACT

OBJECTIVE: To assess the marginal and bacterial microleakage in zirconia and CAD-CAM or cast Co-Cr implant abutments.

METHODS: Sixty-four conical connection implants with their respective abutments were divided into four groups (Co-Cr (milled, laser-sintered and cast) and Zirconia (milled)). All specimens were subjected to a chewing simulation and thermocycling. After aging process, specimens were submerged in a 0.2% methylene blue solution with Porphyromonas gingivalis (P.g) for 48 h. The marginal microleakage was measured by using a 40× optical microscopy at the internal part of the implant, and when positive microleakage was observed, a DNA isolation with a polymerase chain reaction (PCR) test was used. The microbiological assessment was based on colony forming units (CFUs).

RESULTS: Thirty (47%) implant-abutments presented microleakage and the PCR was performed on those specimens (1 Zirconia, 1 Co-Cr milled, 14 Co-Cr laser-sintered and 14 cast). Seven specimens (1 Co-Cr laser-sintered and 6 cast) presented values below the PCR detection limit (< 100 CFUs). The lowest CFUs count occurred in the Co-Cr milled group (5.17E+02 CFUs/ml) followed by zirconia (7.70E+03 CFUs/mL). The Co-Cr cast (9.39E+03 CFUs/ml) and laser-sintered (2.4E+05 CFUs/ml) groups had higher bacterial count. The CFU count comparison performed between Co-Cr cast and laser-sintered resulted in a statistically significant differences in favor of Co-CrCL (p < 0.05).

CONCLUSIONS: The abutment material and fabrication technique affected the implant-abutment microleakage. Although the CAD-CAM abutments presented favorable results, all tested groups presented microleakage.

PMID:35818785 | DOI:10.1111/clr.13973

Stat Methods Med Res. 2022 Jul 12:9622802221111546. doi: 10.1177/09622802221111546. Online ahead of print.

ABSTRACT

Recently, various methods have been developed to estimate the sample mean and standard deviation when only the sample size, and other selected sample summaries are reported. In this paper, we provide a unified approach to optimal estimation that can be easily adopted when only some summary statistics are reported. We show that the proposed estimators have the lowest variance among linear unbiased estimators. We also show that in the most commonly reported cases, that is, when only a three-number or five-number summary is reported, the newly proposed estimators match the previously developed estimators. Finally, we demonstrate the performance of the estimators numerically.

PMID:35818759 | DOI:10.1177/09622802221111546

Stat Methods Med Res. 2022 Jul 12:9622802221111559. doi: 10.1177/09622802221111559. Online ahead of print.

ABSTRACT

Interval-censored failure time and panel count data, which frequently arise in medical studies and social sciences, are two types of important incomplete data. Although methods for their joint analysis have been available in the literature, they did not consider the observation process, which may depend on the failure time and/or panel count of interest. This study considers a three-component joint model to analyze interval-censored failure time, panel counts, and the observation process within a unique framework. Gamma and distribution-free frailties are introduced to jointly model the interdependency among the interval-censored data, panel count data, and the observation process. We propose a sieve maximum likelihood approach coupled with Bernstein polynomial approximation to estimate the unknown parameters and baseline hazard function. The asymptotic properties of the resulting estimators are established. An extensive simulation study suggests that the proposed procedure works well for practical situations. An application of the method to a real-life dataset collected from a cardiac allograft vasculopathy study is presented.

PMID:35818765 | DOI:10.1177/09622802221111559

Clin Linguist Phon. 2022 Jul 12:1-16. doi: 10.1080/02699206.2022.2096483. Online ahead of print.

ABSTRACT

Adductor spasmodic dysphonia (ADSD) is a neurological dystonia characterised by involuntary adductor spasms of the larynx during speech. Spasm frequency is often reported to increase during syllables that begin with voiced speech sounds, especially glottal stops. Because of its underlying physical and acoustic complexities, the voicing contrast in American English (AE) appears unlikely to interact consistently with a singular physical phenomenon like laryngeal spasm. This retrospective study investigated additional phonetic contrasts and their relationship to spasm frequency. Standardised, 144-word recordings of 36 participants with adductor spasmodic dysphonia were analysed. Productions were coded for rater-perceived syllable stress, voiced/voiceless onset, vowel/consonant onset, and word-onset place and manner of production. Phonetic contexts were compared using independent sample t-tests and Kruskal-Wallis statistics. Contexts in which spasm varied significantly included stressed/unstressed syllables, content/function words, and multisyllabic/monosyllabic words. Study results reaffirm the clinical usefulness of standardised ADSD/ABSD sentences during differential diagnosis but conflict with previous studies that report a connection between ADSD spasm and phoneme voicing.

PMID:35818753 | DOI:10.1080/02699206.2022.2096483

Clin Exp Dent Res. 2022 Jul 11. doi: 10.1002/cre2.589. Online ahead of print.

ABSTRACT

OBJECTIVES: The aim of this study was to validate an active matrix metalloproteinase (MMP-8) point-of-care diagnostic tool in COVID-19 patients with periodontal disease.

SUBJECTS, MATERIALS, AND METHODS: Seventy-two COVID-19-positive and 30 COVID-19-negative subjects were enrolled in the study. Demographic data were recorded, periodontal examination carried out, and chairside tests run for evaluating the expression of active MMP-8 (aMMP-8) in the site with maximum periodontal breakdown via gingival crevicular fluid sampling as well as via a mouth rinse-based kit for general disease activity. In COVID-19-positive patients, the kits were run again once the patients turned COVID-19 negative.

RESULTS: The overall (n = 102) sensitivity/specificity of the mouthrinse-based kits to detect periodontal disease was 79.41%/36.76% and that of site-specific kits was 64.71%/55.88% while adjusting for age, gender, and smoking status increased the sensitivity and specificity (82.35%/76.47% and 73.53%/88.24, respectively). Receiver operating characteristic (ROC) analysis for the adjusted model revealed very good area under the ROC curve 0.746-0.869 (p < .001) and 0.740-0.872 (p < .001) (the aMMP-8 mouth rinse and site-specific kits, respectively). No statistically significant difference was observed in the distribution of results of aMMP-8 mouth rinse test (p = .302) and aMMP-8 site-specific test (p = .189) once the subjects recovered from COVID-19.

CONCLUSIONS: The findings of the present study support the aMMP-8 point-of-care testing (PoCT) kits as screening tools for periodontitis in COVID-19 patients. The overall screening accuracy can be further increased by utilizing adjunctively risk factors of periodontitis. The reported noninvasive, user-friendly, and objective PoCT diagnostic methodology may provide a way of stratifying risk groups, deciding upon referrals, and in the institution of diligent oral hygiene regimens.

PMID:35818743 | DOI:10.1002/cre2.589

Eur J Ophthalmol. 2022 Jul 11:11206721221113199. doi: 10.1177/11206721221113199. Online ahead of print.

ABSTRACT

PURPOSE: To investigate the role of oxidative stress and antioxidant system in the etiopathogenesis of pseudoexfoliation and progression of pseudoexfoliation syndrome to glaucoma.

MATERIAL AND METHOD: A total of 20 patients with pseudoexfoliation syndrome, 20 with pseudoexfoliation glaucoma, 20 with primary open-angle glaucoma, and 20 without pseudoexfoliation and glaucoma as a control group, who underwent cataract or glaucoma surgery between December 2020 and March 2021 in the Health Sciences University Beyoğlu Eye Training and Research Hospital, 80 patients were included in the study. Best corrected visual acuity (BCVA), intraocular pressure with applanation tonometry, detailed anterior and posterior segment examinations with biomicroscopy were performed in all patients included in the study. Approximately 0.1 cc of anterior chamber fluid was taken from all patients at the beginning of surgery. Total Oxidant Status (TOS) and Total Antioxidant Status (TAS) levels were measured by keeping the samples taken in the deep freezer of the cornea bank at -80 degrees, transferring them with cold chain transport rules, and examining them with automatic measurement method in the laboratories of the Medical Biochemistry Department of the University of Health Sciences. Oxidative Stress Index (OSI) value was calculated to measure the degree of oxidative stress.

RESULTS: TAS averages of the control and POAG groups were found to be statistically significantly higher than the PES and PEG groups (p = 0.0001, p = 0.0001). No significant difference was observed between the other groups (p > 0.05). The TOS averages of the control and POAG groups were found to be statistically significantly lower than the PES and PEG groups (p = 0.003, p = 0.0001; p = 0.01, p = 0.001), no statistically significant difference was observed between the other groups (p > 0.05). The OSI mean of the control and POAG groups was found to be statistically significantly lower than the PES and PEG groups (p = 0.001, p = 0.0001; p = 0.002, p = 0.0001), no statistically significant difference was observed between the other groups (p > 0.05).

CONCLUSION: Increased TOS and OSI and decreased TAS levels in the aqueous humour of patients with PES and PEG suggest that increased oxidative stress and decreased antioxidative defense system play a role in the etiopathogenesis of the disease.

PMID:35818741 | DOI:10.1177/11206721221113199

Natl Med J India. 2021 Nov-Dec;34(6):359-362. doi: 10.25259/NMJI_414_20.

ABSTRACT

Background In medical education, the need to obtain reliable and valid assessments is critical for the learning process. This study implemented a post-validation item analysis to create a supply of valid questions for incorporation into the question bank. Methods A cross-sectional study was performed in the College of Medicine, University of Bisha, Saudi Arabia. The study was targeting 250 items and 750 distractors from 2017 to 2020. The post-validation item analysis was done to evaluate the quality of the items using test-scoring and reporting software. Data were analysed by SPSS Version 25. Quantitative variables were expressed as mean (SD), while qualitative variables were expressed as number and percentage. An independent t-test was done to reveal the association between the item analysis parameters. A value of p<0.05 was considered statistically significant. Results The mean difficulty index (DIF I), discrimination index (DI) and distractors efficacy (DE) were 73.8, 0.26 and 73.5%, respectively. Of 250 items, 38.8% had an acceptable DIF I (30%-70%) and 66.4% had ‘good to excellent’ DI (>0.2). Of 750 distractors, 33.6%, 37%, 20% and 9.2% had zero, one, two and three non-functional distractors, respectively. The mean Kuder-Richardson was 0.76. The DIF I was significantly associated with DE (p=0.048). The post-validation item analysis of this study showed that a considerable proportion of questions had acceptable parameters and were recommended for item banking. However, some questions needed to be rephrased and reassessed or discarded. Conclusion Three-option multiple-choice questions should be considered for future examinations to improve the assessment process.

PMID:35818102 | DOI:10.25259/NMJI_414_20