Category: Statistics

Exp Gerontol. 2022 Jul 1:111884. doi: 10.1016/j.exger.2022.111884. Online ahead of print.

ABSTRACT

INTRODUCTION: Sarcopenia, the age-related loss of skeletal muscle strength and mass, carries a significant burden for affected individuals. There has been little investigation of sarcopenia using experimental medicine techniques to study human muscle tissue in detail. The aim of the Muscle Ageing Sarcopenia Studies Lifecourse (MASS_Lifecourse) study is to recruit up to 160 participants, equally divided between females and males between ages 45 and 85 years for detailed phenotyping of skeletal muscle health. Here we describe the protocol for the study and the characteristics of the first 80 participants.

METHODS: We are recruiting participants from three sources in the north-east of England. Study fieldwork comprises a home visit (or videocall) for consent and assessment of health, cognition, lifestyle, and wellbeing. This is followed by a visit to a clinical research facility for assessment of sarcopenia status and collection of samples including a vastus lateralis muscle biopsy. We produced descriptive statistics for the first 80 participants, including expressing their grip strength relative to normative data in the form of Z-scores.

RESULTS: The first 80 participants (53.8 % female) covered the target ages, ranging from 48 to 84 years. They were regularly physically active, reported good physical function and had a prevalence of sarcopenia (including probable sarcopenia) of 11.3 % based on the revised European consensus. Their grip strength was similar to that in the general population, with a mean Z-score of 0.09 standard deviations (95 % CI: -1.64, 1.83) above that expected.

CONCLUSIONS: The MASS_Lifecourse study combines comprehensive health and lifestyle data with a range of biological samples including skeletal muscle. The findings from planned analyses should contribute to improvements in the diagnosis, treatment, and prevention of sarcopenia.

PMID:35788023 | DOI:10.1016/j.exger.2022.111884

Urology. 2022 Jul 1:S0090-4295(22)00517-9. doi: 10.1016/j.urology.2022.05.038. Online ahead of print.

ABSTRACT

OBJECTIVE: To determine whether the omission of pre-procedure genitourinary exam for vasectomy inherent to a virtual consultation reduces the likelihood of successfully completing in-office vasectomy. Currently, the AUA Vasectomy guidelines encourage in-person examination when possible, though COVID-19 has catalyzed the uptake of virtual consultations at many institutions. We hypothesized that rates of completed in-office vasectomy do not significantly differ between patients examined during consultation in the office and those seen virtually with no exam.

METHODS: Virtual vasectomy consults from April to December 2020 were retrospectively reviewed and compared to a size-matched, randomly-selected control group who underwent in-office vasectomy consultation. The primary outcome was completion of in-office bilateral vasectomy. Baseline demographic characteristics were compared. Fisher’s exact test and Student’s t-test were performed on categorical and continuous variables, respectively.

RESULTS: Of 211 patients who underwent virtual vasectomy consultation during the study period, 153 presented for in-office vasectomy. They were compared to 153 vasectomies from the in-person consult cohort. No demographic differences were observed between virtual and in-office consult groups. No statistical difference was observed in completion rates of in-office vasectomy, which was 97.4% (149/153) in the virtual consult cohort and 98.7% (151/153) in the in-office consultation cohort (p = 0.68).

CONCLUSIONS: Rates of completed in-office vasectomy did not significantly differ based on consult platform, suggesting that a pre-vasectomy physical exam is not required to predict successful completion of the procedure. Telehealth should be utilized as an additional platform to improve access for male contraceptive procedures in a young and busy population.

PMID:35788017 | DOI:10.1016/j.urology.2022.05.038

Int J Biol Macromol. 2022 Jul 1:S0141-8130(22)01363-0. doi: 10.1016/j.ijbiomac.2022.06.150. Online ahead of print.

ABSTRACT

This study presents the preparation of cellulose micro-nanofibrils (CMNFs) from Enteromorpha (EP) and the application in PVA/acetylated distarch phosphate (ADSP)/CMNFs composite films. The Micro-nano scale, hydrophilicity, and strong hydrogen bond characteristics of CMNFs prepared form EP by acid hydrolysis were confirmed through the granular statistics, XRD analysis and chemical structure analysis. With the addition of CMNFs, the ultimate tensile strength and elongation at break of composite films are increased by 42.4 % and 90.3 %. An original Weibull statistical analysis shows the impact of CMNFs’ added amount on strength distribution and ultimate stress. SEM and polarizing microscope images show the CMNFs’ dispersion state in that films is optimal, when their addition was to be 2 %-3 % of total dry weight of PVA/ADSP matrix， which is consistent with the results of Weibull modulus analysis. The main thermal weight-loss process of the composite film is divided into four stages, CMNFs can significantly increase the thermostability at 280 °C to 400 °C. The experiment of water contact angle and water vapor transmission rate of the composite films confirmed that CMNFs can improve films’ hydrophilicity. This study provides basis for the preparation of hydrophilic CMNFs and mechanism of modification study PVA-based composites.

PMID:35788004 | DOI:10.1016/j.ijbiomac.2022.06.150

Burns. 2022 Jun 22:S0305-4179(22)00160-7. doi: 10.1016/j.burns.2022.06.010. Online ahead of print.

ABSTRACT

BACKGROUND: Intermittent Fasting (IF) has proved to have various positive effects on life span, diseases, and healing of tissues in rodents. We evaluated the protective effect of fasting in maintaining the ischemic zones in burn wounds.

METHODS: In this study, 20 rats were divided into two groups where the IF rats were deprived of food for three months. Burn wounds were created by burn comb model on the back of all rats. On days 3 and 21 after injury, five rats in each group were euthanized whereby samples were collected for histopathological, immunohistochemical (Bcl2, P53 and VEGF), and biochemical (MDA, TAC, HP) evaluations.

RESULTS: Histopathological analysis revealed epithelial layer and zone of ischemia remained viable in the intermittent fasting group on day 3. On the 21st day, epithelialization, angiogenesis, inflammation, fibrocyte-fibroblast, and collagen density were different in the ischemic and necrotic zones between the control and intermittent fasting groups (p<0.05). We found no statistical differences in Bcl2, P53, VEGF, MDA, TAC, and HP on day 3 between the intermittent fasting and control groups.

CONCLUSIONS: Intermittent fasting before burn wounds reduces tissue damage caused by ischemia and enhanced the viability of cells in zone of stasis. It also accelerated wound healing by increasing epithelialization and collagen production in the skin and regulating inflammatory responses. This intervention appears to be related to better collagen arrangement and angiogenesis.

PMID:35787965 | DOI:10.1016/j.burns.2022.06.010

Burns. 2022 Jun 10:S0305-4179(22)00144-9. doi: 10.1016/j.burns.2022.06.003. Online ahead of print.

ABSTRACT

Low- and middle-income countries (LMICs) remain drastically underrepresented in health research, with African countries producing less than 1% of the global output. This work investigates authorship patterns of publications on burns in LMICs. Original research studies addressing burn injuries in LMICs and published between 1st January 2015 and 31st December 2020 were included in the review. Descriptive statistics were performed for country affiliations of authors, World Bank Country Income Groups, WHO group, study-focus and country studied. Of the 458 results, 426 studies met the inclusion criteria. Nearly a quarter of papers on burns in LMICs had both first and senior authors from high-income countries (HICs, n = 95, 24.4%), more than half of the papers had both first and senior authors from upper middle- income countries (upper MICs, n = 222, 57.2%), while less than 1% (n = 3) had first and senior authors exclusively from lower-income countries (LICs). Eleven percent (n = 41/388) of all papers were written without either first nor senior author being from the country studied, and 17 of them (41%) had both first and senior authors from the USA. Twenty-five (6%) of the papers had the first author and not the senior author from the country of focus, while six (2%) had the senior and not the first author from the country of interest. To overcome global health challenges such as burns, locally led research is imperative. The maximum benefit of HIC-LMIC collaborations is achieved when LMICs play an active role in leading the research. When LMICs direct the research being conducted in their country, the harm of inherently inequitable relationships is minimized.

PMID:35787966 | DOI:10.1016/j.burns.2022.06.003

World Neurosurg. 2022 Jul 1:S1878-8750(22)00914-7. doi: 10.1016/j.wneu.2022.06.129. Online ahead of print.

ABSTRACT

OBJECTIVE: Angiographic treatment of asymptomatic cerebral vasospasm in aneurysmal subarachnoid hemorrhage remains controversial. We sought to investigate its relationship with the development of delayed cerebral ischemia.

METHODS: Consecutive patients admitted between July 2017 and June 2019, with a diagnosis of aneurysmal subarachnoid hemorrhage, were retrospectively analyzed. The rate of development of delayed cerebral ischemia was compared between a group of patients who underwent cerebral angiography for asymptomatic cerebral vasospasm and those who did not. The Mann-Whitney U test or chi-square test was used to compare the two groups.

RESULTS: 37 of the 94 patients with aneurysmal subarachnoid hemorrhage were screened for cerebral vasospasm, of whom 16 (43%) had moderate-severe vasospasm. When patients who underwent therapeutic cerebral angiography were compared with those who did not, and after adjusting for sex, age, and grade of subarachnoid hemorrhage, treatment was not found to be significantly associated with delayed cerebral ischemia (HR=0.82, 95% CI: 0.19-3.52, p=0.79). We found that the median length of stay in the intensive care unit and hospital increased significantly with the severity of cerebral vasospasm (p<0.001).

CONCLUSIONS: Cerebral angiography has a low rate of detecting moderate-severe cerebral vasospasm in asymptomatic patients. Moreover, there was no statistically significant difference in the rate of delayed cerebral ischemia between asymptomatic patients treated versus those not treated for cerebral vasospasm.There was significant association between the severity of CVS and the ICU and hospital length of stay. More studies are needed to evaluate the utility of treating asymptomatic cerebral vasospasm in high-grade aneurysmal subarachnoid hemorrhage.

PMID:35787959 | DOI:10.1016/j.wneu.2022.06.129

Dent Mater. 2022 Jul 1:S0109-5641(22)00193-2. doi: 10.1016/j.dental.2022.06.033. Online ahead of print.

ABSTRACT

OBJECTIVE: Evaluate the effect of different restorative filling techniques on the residual shrinkage stress (ShrS), cuspal strain (CS), depth of cure (DC), and enamel crack formation (Ec) in molars with MOD restorations.

METHODS: Post-gel shrinkage, elastic modulus, compressive and diametral tensile strength of the Filtek One Bulk Fill composite were calculated. Sixty molars with MOD preparations were restored using four filling techniques: Bulk; Horizontal; Oblique; Natural enamel and dentin substitution (NEDS) technique. CS was measured using a strain gauge (n = 10). The DC (n = 5) was measured using Knoop hardness. Shrinkage stress/strain was analyzed using 3D finite element analysis. The Ec analysis was carried out by transillumination. Two-way ANOVA with repeated measures and Tukey’s HSD test (α = 0.05) was performed for the CS data. Two-Way ANOVA and Tukey’s HSD test was performed for the DC data (α = 0.05).

RESULTS: CS was higher at the lingual cusp for the horizontal and NEDS technique. No statistical difference was found between the buccal and lingual CS values for the Bulk (p = 0.367) or Oblique techniques (p = 0.192). CS values were lower for the Bulk. More enamel cracks were found for the Bulk. DC was lower at 4 mm regardless the filling technique. The Horizontal showed the highest ShrS values. The Bulk generated the lower ShrS values.

SIGNIFICANCE: A Bulk technique caused the lowest shrinkage stress/strain. An Oblique technique yielded the best balance between stress, strain and crack formation. NEDS technique is a good alternative to decrease the number of increments while maintaining the stress levels nearby the Oblique technique.

PMID:35787894 | DOI:10.1016/j.dental.2022.06.033

Mayo Clin Proc. 2022 Jul;97(7):1339-1344. doi: 10.1016/j.mayocp.2022.02.026.

ABSTRACT

The use and misuse of prescription stimulants has escalated during the past decade, with concerns of being “the next epidemic.” The diagnosis of attention-deficit/hyperactivity disorder and the use of prescription stimulants have rapidly increased in children and adults in the past decade. Amphetamine use more than doubled from 2006 to 2016. In 2018, among illicit substance users in the past year (53.2 million), more than 5 million 12 years or older had misused prescription stimulants. The most commonly reported motivations for misuse were to help with alertness and concentration, in approximately 60% of respondents. Most persons who misused prescription stimulants received the medication from a friend or relative, who got it through a health care provider. It is important to reexamine the pattern of prescription stimulant use after the loosening of Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) criteria for attention-deficit/hyperactivity disorder diagnosis. Caveats to the this report could be the understudied specific populations (such as medical students), the exclusion of the military and institutionalized populations from the study, and the variations among individual states in stimulant prescribing patterns.

PMID:35787861 | DOI:10.1016/j.mayocp.2022.02.026

Prev Med. 2022 Jul 1:107127. doi: 10.1016/j.ypmed.2022.107127. Online ahead of print.

ABSTRACT

It is well known that the statistical analyses in health-science and medical journals are frequently misleading or even wrong. Despite many decades of reform efforts by hundreds of scientists and statisticians, attempts to fix the problem by avoiding obvious error and encouraging good practice have not altered this basic situation. Statistical teaching and reporting remain mired in damaging yet editorially enforced jargon of “significance”, “confidence”, and imbalanced focus on null (no-effect or “nil”) hypotheses, leading to flawed attempts to simplify descriptions of results in ordinary terms. A positive development amidst all this has been the introduction of interval estimates alongside or in place of significance tests and P-values, but intervals have been beset by similar misinterpretations. Attempts to remedy this situation by calling for replacement of traditional statistics with competitors (such as pure-likelihood or Bayesian methods) have had little impact. Thus, rather than ban or replace P-values or confidence intervals, we propose to replace traditional jargon with more accurate and modest ordinary-language labels that describe these statistics as measures of compatibility between data and hypotheses or models, which have long been in use in the statistical modeling literature. Such descriptions emphasize the full range of possibilities compatible with observations. Additionally, a simple transform of the P-value called the surprisal or S-value provides a sense of how much or how little information the data supply against those possibilities. We illustrate these reforms using some examples from a highly charged topic: trials of ivermectin treatment for Covid-19.

PMID:35787846 | DOI:10.1016/j.ypmed.2022.107127

Arch Phys Med Rehabil. 2022 Jul 1:S0003-9993(22)00485-3. doi: 10.1016/j.apmr.2022.06.003. Online ahead of print.

ABSTRACT

OBJECTIVE: This systematic review and meta-analysis aimed to review and quantify the changes in gait parameters after therapeutic intervention in adults with neurological disorders.

DATA SOURCES: A keyword search was performed in four databases: PubMed, CINAHL, Scopus, and Web of Science (01/2000-12/2021). We performed the search algorithm including all possible combinations of keywords. Full-text articles were examined further using forward/backward search methods.

STUDY SELECTION: Studies were thoroughly screened using the following inclusion criteria: Study design: Randomized Controlled Trial (RCT); adults ≥ 55 years old with a neurological disorder; therapeutic intervention; spatiotemporal gait characteristics; and Language: English.

DATA EXTRACTION: A standardized data extraction form was used to collect the following methodological outcome variables from each of the included studies: author, year, population, age, sample size, and spatiotemporal gait parameters such as cadence, step length, step width, or double limb support. A meta-analysis was performed among trials presenting with similar characteristics, including study population and outcome measure. If heterogeneity was > 50%, a random plot analysis was used, otherwise, a fixed plot analysis was done.

DATA SYNTHESIS: We included 25 out of 34 studies in our meta-analysis that examined gait in adults with neurological disorders. All analyses used effect sizes and standard error and a p < 0.05 threshold was considered statistically significant. Overall, we found that sensory (SS) and electrical stimulation (ES) had the most significant effect on step length (SS: z=5.44*, ES: z=2.42*) and gait speed (SS: z=6.19*, ES: z=7.38*) in adults with Parkinson’s disease (PD). Although balance or physical activity interventions were not found to be effective in modifying step length in adults with PD, they showed a significant effect on gait speed. Further, physical activity had the most significant effect on cadence in adults with PD (z=2.84*) relative to sensory stimulation effect on cadence (z=2.59*). For stroke, conventional physical therapy had the most significant effect on step length (z=3.12*) and cadence (z=3.57*).

CONCLUSION: Sensory stimulation such as auditory and somatosensory stimulation while walking had the most significant effect on step length in adults with PD. We also found that conventional PT did improve spatial gait parameters relative to other physical activity interventions in adults with PD and stroke.

PMID:35787837 | DOI:10.1016/j.apmr.2022.06.003