Category: Statistics

J Neurosurg Spine. 2021 Nov 26:1-11. doi: 10.3171/2021.8.SPINE21651. Online ahead of print.

ABSTRACT

OBJECTIVE: Degenerative cervical myelopathy (DCM) is a major global cause of spinal cord dysfunction. Surgical treatment is considered a safe and effective way to improve functional outcome, although information about long-term functional outcome remains scarce despite increasing longevity. The objective of this study was to describe functional outcome 10 years after surgery for DCM.

METHODS: A prospective observational cohort study was undertaken in a university-affiliated neurosurgery department. All patients who underwent surgery for DCM between 2008 and 2010 as part of the multicenter Cervical Spondylotic Myelopathy International trial were included. Participants were approached for additional virtual assessment 10 years after surgery. Functional outcome was assessed according to the modified Japanese Orthopaedic Association (mJOA; scores 0-18) score at baseline and 1, 2, and 10 years after surgery. The minimal clinically important difference was defined as 1-, 2-, or 3-point improvement for mild, moderate, and severe myelopathy, respectively. Outcome was considered durable when stabilization or improvement after 2 years was maintained at 10 years. Self-evaluated effect of surgery was assessed using a 4-point Likert-like scale. Demographic, clinical, and surgical data were compared between groups that worsened and improved or remained stable using descriptive statistics. Functional outcome was compared between various time points during follow-up with linear mixed models.

RESULTS: Of the 42 originally included patients, 37 participated at follow-up (11.9% loss to follow-up, 100% response rate). The mean patient age was 56.1 years, and 42.9% of patients were female. Surgical approaches were anterior (76.2%), posterior (21.4%), or posterior with fusion (2.4%). The mean follow-up was 10.8 years (range 10-12 years). The mean mJOA score increased significantly from 13.1 (SD 2.3) at baseline to 14.2 (SD 3.3) at 10 years (p = 0.01). A minimal clinically important difference was achieved in 54.1%, and stabilization of functional status was maintained in 75.0% in the long term. Patients who worsened were older (median 63 vs 52 years, p < 0.01) and had more comorbidities (70.0% vs 25.9%, p < 0.01). A beneficial effect of surgery was self-reported by 78.3% of patients.

CONCLUSIONS: Surgical treatment for DCM results in satisfactory improvement of functional outcome that is maintained at 10-year follow-up.

PMID:34826817 | DOI:10.3171/2021.8.SPINE21651

Neural Netw. 2021 Nov 16;146:1-10. doi: 10.1016/j.neunet.2021.11.010. Online ahead of print.

ABSTRACT

Prescription of Traditional Chinese Medicine (TCM) is a precious treasure accumulated in the long-term development of TCM. Artificial intelligence (AI) technology is used to build herb recommendation models to deeply understand regularities in prescriptions, which is of great significance to clinical application of TCM and discovery of new prescriptions. Most of herb recommendation models constructed in the past ignored the nature information of herbs, and most of them used statistical models based on bag-of-words for herb recommendation, which makes it difficult for the model to perceive the complex correlation between symptoms and herbs. In this paper, we introduce the properties of herbs as additional auxiliary information by constructing herb knowledge graph, and propose a graph convolution model with multi-layer information fusion to obtain symptom feature representations and herb feature representations with rich information and less noise. We apply the proposed model to the TCM prescription dataset, and the experiment results show that our model outperforms the baseline models in terms of Precision@5 by 6.2%, Recall@5 by 16.0% and F1-Score@5 by 12.0%.

PMID:34826774 | DOI:10.1016/j.neunet.2021.11.010

J Neurosurg Spine. 2021 Nov 26:1-8. doi: 10.3171/2021.8.SPINE21330. Online ahead of print.

ABSTRACT

OBJECTIVE: Robotics is a major area for research and development in spine surgery. The high accuracy of robot-assisted placement of thoracolumbar pedicle screws is documented in the literature. The authors present the largest case series to date evaluating 90-day complication, revision, and readmission rates for robot-assisted spine surgery using the current generation of robotic guidance systems.

METHODS: An analysis of a retrospective, multicenter database of open and minimally invasive thoracolumbar instrumented fusion surgeries using the Mazor X or Mazor X Stealth Edition robotic guidance systems was performed. Patients 18 years of age or older and undergoing primary or revision surgery for degenerative spinal conditions were included. Descriptive statistics were used to calculate rates of malpositioned screws requiring revision, as well as overall complication, revision, and readmission rates within 90 days.

RESULTS: In total, 799 surgical cases (Mazor X: 48.81%; Mazor X Stealth Edition: 51.19%) were evaluated, involving robot-assisted placement of 4838 pedicle screws. The overall intraoperative complication rate was 3.13%. No intraoperative implant-related complications were encountered. Postoperatively, 129 patients suffered a total of 146 complications by 90 days, representing an incidence of 16.1%. The rate of an unrecognized malpositioned screw resulting in a new postoperative radiculopathy requiring revision surgery was 0.63% (5 cases). Medical and pain-related complications unrelated to hardware placement accounted for the bulk of postoperative complications within 90 days. The overall surgical revision rate at 90 days was 6.63% with 7 implant-related revisions, representing an implant-related revision rate of 0.88%. The 90-day readmission rate was 7.13% with 2 implant-related readmissions, representing an implant-related readmission rate of 0.25% of cases.

CONCLUSIONS: The results of this multicenter case series and literature review suggest current-generation robotic guidance systems are associated with low rates of intraoperative and postoperative implant-related complications, revisions, and readmissions at 90 days. Future outcomes-based studies are necessary to evaluate complication, revision, and readmission rates compared to conventional surgery.

PMID:34826805 | DOI:10.3171/2021.8.SPINE21330

Arch Gerontol Geriatr. 2021 Nov 16;98:104576. doi: 10.1016/j.archger.2021.104576. Online ahead of print.

ABSTRACT

BACKGROUND: This study evaluated the association between changes in physical performance and blood pressure (BP) (e.g., systolic [SBP], diastolic [DBP], pulse pressure) in older women.

METHODS: 5627 women (mean age 69.8 ± 3.7 y) with grip strength, chair stand, gait speed performance and clinic-measured BP at baseline and at least one follow-up (years 1, 3 or 6) were included. Generalized estimating equation analysis of multivariable models with standardized point estimates described the longitudinal association between physical performance and BP changes in the overall cohort, and in models stratified by baseline cardiovascular disease (CVD), time-varying antihypertensive medication use (none, ≥1) and enrollment age (65-69 y; 70-79 y).

RESULTS: Overall, each z-score unit increment in grip strength was associated with 0.59 mmHg (95% CI 0.10, 1.08) higher SBP, and 0.39 mmHg (95% CI 0.11, 0.67) higher DBP. In stratified models, a standardized increment in grip strength was associated with higher SBP in women without CVD (0.81; 95% CI 0.23-1.39), among antihypertensive medication users (0.93; 95% CI 0.44, 1.41) and non-users (0.37; 95% CI 0.03, 0.71), and in those aged 65-69 y (0.64; 95% CI 0.04, 1.24). Similarly, a standardized increment in any of the three performance measures was associated with modestly higher DBP in antihypertensive medication users, and those aged 70-79 y. Associations between any performance measure and pulse pressure change were not significant.

CONCLUSION: These results suggest a positive, and statistically significant relationship between physical performance and BP that appears to be influenced by CVD history, antihypertensive medication use, and age.

PMID:34826770 | DOI:10.1016/j.archger.2021.104576

Clin Imaging. 2021 Nov 22;82:150-155. doi: 10.1016/j.clinimag.2021.11.006. Online ahead of print.

ABSTRACT

PURPOSE: To evaluate if a computer-aided diagnosis (CAD) system on ultrasound (US) can improve the diagnostic performance of inexperienced radiologists.

METHODS: We collected ultrasound images of 256 breast lesions taken between March and May 2020. We asked two experienced and two inexperienced radiologists to retrospectively review the US features of each breast lesion according to the Breast Imaging Reporting and Data System (BI-RADS) categories. A CAD examination with S-Detect™ software (Samsung Healthcare, Seoul, South Korea) was conducted retrospectively by another uninvolved radiologist blinded to the BIRADS values previously attributed to the lesions. Diagnostic performances of experienced and inexperienced radiologists and CAD were compared and the inter-observer agreement among radiologists was calculated.

RESULTS: The diagnostic performance of the experienced group in terms of sensitivity was significantly higher than CAD (p < 0.001). Conversely, the diagnostic performance of inexperienced group in terms of both sensitivity and specificity was significantly lower than CAD (p < 0.001). We obtained an excellent agreement in the evaluation of the lesions among the two expert radiologists (Kappa coefficient: 88.7%), and among the two non-expert radiologists (Kappa coefficient: 84.9%).

CONCLUSION: The US CAD system is a useful additional tool to improve the diagnostic performance of the inexperienced radiologists, eventually reducing the number of unnecessary biopsies. Moreover, it is a valid second opinion in case of experienced radiologists.

PMID:34826773 | DOI:10.1016/j.clinimag.2021.11.006

Forensic Sci Int. 2021 Nov 19;330:111108. doi: 10.1016/j.forsciint.2021.111108. Online ahead of print.

ABSTRACT

OBJECTIVE: This study aims to generate a statistical model based on magnetic resonance imaging of the knee and radiography of third molars in the lower jaw, for assessing age relative to the 18-year old threshold.

METHODS: In total, 58 studies correlating knee or tooth development to age were assessed, 5 studies for knee and 7 studies for tooth were included in the statistical model. The relation between the development of the anatomical site, based on a binary system, and age were estimated using logistic regression. Separate meta-populations for knee and tooth were generated from the individual based data for men and women. A weighted estimate of probabilities was made by combining the probability densities for knee and tooth. Margin of errors for males and females in different age groups and knee and tooth maturity were calculated within the larger framework of transition analysis using a logit model as a base. Evidentiary values for combinations of knee and tooth maturity were evaluated with likelihood ratios.

RESULTS: For males, the sensitivity for the method was calculated to 0.78 (probability of correctly classifying adults), the specificity 0.90 (probability of correctly classifying minors), the negative predictive value 0.80 (proportion identified minors are minors) and the positive predictive value 0.89 (proportion identified adults are adults) indicating a model better at identifying minors than adults. The point at which half the female population has reached closed knee lies before the 18-year threshold, adding the knee as an indicator lowers specificity and increases sensitivity. The sensitivity when using tooth as an indicator for females is 0.24 and specificity 0.97, signifying few minors misclassified as adults but also a low probability of identifying adults. The negative predictive value for women when using tooth as the sole indicator is 0.56 and positive predictive value 0.88. Probabilities were calculated for males and females assuming a uniform age distribution between 15 and 21years. The calculated margin of error of minors classified as adults in a population between 15 and 21 years with the model was 11% for males and 12% for females. Further, the evidentiary value as well as margin of error vary for different combinations of knee and tooth maturity.

CONCLUSION: The statistical model based on the combination of MRI knee and radiography of mandibular third molars is a valid method to assess age relative to the 18-year old threshold when applied on males and of limited value in females.

PMID:34826761 | DOI:10.1016/j.forsciint.2021.111108

Int J Med Inform. 2021 Nov 18;158:104626. doi: 10.1016/j.ijmedinf.2021.104626. Online ahead of print.

ABSTRACT

BACKGROUND: The prevalence of clinical inertia, the failure of appropriate treatment intensification in diabetes treatment, is a well-documented worldwide phenomenon. This project addresses the problem of clinical inertia through three interrelated activities, clinical decision support (CDSS), team-based care, and patient engagement in diabetes management.

OBJECTIVES: The purpose of this research is to provide analysis under the State-University Partnership Learning Network regarding the impact of an electronic decision support tool combined with team-based care workflow on provider decision-making and patient outcomes for the treatment of poorly controlled diabetes mellitus (diabetes) among patients receiving Kentucky Medicaid. The objectives of this study are to 1) assess clinical outcomes of type 2 diabetes in the Medicaid population with team-based care using CDSS, 2) evaluate physicians’ and pharmacists’ experience on CDSS.

METHODS: This is a quality improvement project using a mixed-method – longitudinal and control group comparison of outcomes based upon clinical measures and online surveys of providers and pharmacists involved in this project.

RESULTS: Patients treated by providers who changed the treatment regimen to one that either fully or partially followed the recommendation of the CDSS tool had a statistically significant reduction in HbA1c with an average initial HbA1c of 10.1 and the final HbA1c of 8. The online survey of physicians shows that more than 80% of physicians agree the use of CDSS will support improved patient outcomes. The use of a team-based care approach that includes pharmacists in implementing treatment changes was broadly supported by both physicians and pharmacists.

CONCLUSION: CDSS combined with team-based care can be effective in reducing HbA1c to targeted therapeutic levels. The use of CDSS provides a way to efficiently assess more than 160 potential frontline drugs and properly accelerate treatment. Consistent with the research literature, the inclusion of pharmacists can play a key role in team-based care to assess treatment alternatives and provide for improvement in outcomes and patient adherence for diabetes. The user surveys show both physicians and pharmacists have a positive attitude toward CDSS.

PMID:34826757 | DOI:10.1016/j.ijmedinf.2021.104626

Prev Vet Med. 2021 Nov 5;198:105533. doi: 10.1016/j.prevetmed.2021.105533. Online ahead of print.

ABSTRACT

Bovine Viral Diarrhea (BVD) is a ubiquitous endemic disease in most bovine populations that causes a negative economic impact on cattle production systems. However, true herd and individual prevalence in Chile have not been estimated based on statistical and epidemiological considerations and uncertainty regarding the infection’s extension at animal and herd levels. In addition, the risk factors that can influence how the infection has spread among the cattle premises have not been assessed yet. Therefore, the study aimed to estimate true herd and animal prevalence of active BVDV infection in pasture-based dairy herds and to evaluate risk factors potentially associated with the status of herds and the within-herd prevalence, using a Bayesian approach. A cross-sectional study was performed over a random stratified (proportional to herd size) sample of one-hundred and fifty dairy herds selected in Chile’s two leading dairy regions (Region de Los Ríos and Region de Los Lagos). We obtained 12.311 blood samples from lactating cows, but 4.998 randomly selected samples were processed due to budget constraints. For estimating BVDV Herd Prevalence (HP), a herd was considered infected if at least one positive animal to Ag-ELISA was found. In addition, a survey was completed on each farm, aiming to collect information to assess the influence of some variables over the state of the herds; both estimations were obtained using a Bayesian approach. True herd prevalence and true individual prevalence of BVDV active infection were estimated at 77 % and 3.5 % respectively, no significant differences were found between characteristics like herd size, location, vaccination, etc. Open herds and herds that mix herd categories are more likely to have higher BVDV prevalence.

PMID:34826733 | DOI:10.1016/j.prevetmed.2021.105533

Clin Neurol Neurosurg. 2021 Nov 18;211:107048. doi: 10.1016/j.clineuro.2021.107048. Online ahead of print.

ABSTRACT

Diffusion Tensor Imaging (DTI) enabled the investigation of brain White Matter (WM), both qualitatively to study the macrostructure, and quantitatively to study the microstructure. The quantitative analyses are mostly performed at the whole-tract level, i.e., providing one measure of interest per tract; however, along-tract approaches may provide finer details of the quality of the WM tracts. In this study, using the DWI data collected from 40 young and 40 old individuals, we compared the DTI measures of FA, MD, AD, and RD, estimated by both whole-tract and along-tract approaches in 18 WM bundles, between the two groups. The results of the whole-tract quantitative analysis showed a statistically significant (p-FWER < 0.05) difference between the old and young groups in 6 tracts for FA, 8 tracts for MD, 1 tract for AD, and 7 tracts for RD. On the contrary, the along-tract approach showed differences between the two groups in 10 tracts for FA, 14 tracts for MD, 8 tracts for AD, and 11 tracts for RD. All the differences between the along-tract measures of the two groups had a large effect size (Cohen’d > 0.80). This study showed that the along-tract approach for the analysis of brain WM reveals changes in some WM tracts which had not shown any changes in the whole-tract approach, and therefore this finding emphasizes the utilization of the along-tract approach along with the whole-tract method for a more accurate study of the brain WM.

PMID:34826755 | DOI:10.1016/j.clineuro.2021.107048

Forensic Sci Int Genet. 2021 Nov 18;56:102633. doi: 10.1016/j.fsigen.2021.102633. Online ahead of print.

ABSTRACT

Sherpa people, one of the high-altitude hypoxic adaptive populations, mainly reside in Nepal and the southern Tibet Autonomous Region. The genetic origin and detailed evolutionary profiles of Sherpas remain to be further explored and comprehensively characterized. Here we analyzed the newly-generated InDel genotype data from 628 Dingjie Sherpas by merging with 4222 worldwide InDel profiles and collected genome-wide SNP data (approximately 600K SNPs) from 1612 individuals in 191 modern and ancient populations to explore and reconstruct the fine-scale genetic structure of Sherpas and their relationships with nearby modern and ancient East Asians based on the shared alleles and haplotypes. The forensic parameters of 57 autosomal InDels (A-InDels) included in our used new-generation InDel amplification system showed that this focused InDel panel is informative and polymorphic in Dingjie Sherpas, suggesting that it can be used as the supplementary tool for forensic personal identification and parentage testing in Dingjie Sherpas. Descriptive findings from the PCA, ADMIXTURE, and TreeMix-based phylogenies suggested that studied Nepal Sherpas showed excess allele sharing with neighboring Tibeto-Burman Tibetans. Furthermore, patterns of allele sharing in f-statistics demonstrated that Nepal Sherpas had a different evolutionary history compared with their neighbors from Nepal (Newar and Gurung) but showed genetic similarity with 2700-year-old Chokhopani and modern Tibet Tibetans. QpAdm/qpGraph-based admixture sources and models further showed that Sherpas, core Tibetans, and Chokhopani formed one clade, which could be fitted as having the main ancestry from late Neolithic Qijia millet farmers and other deep ancestries from early Asians. Chromosome painting profiles and shared IBD fragments inferred from fineSTRUCTURE and ChromoPainter not only confirmed the abovementioned genomic affinity patterns but also revealed the fine-scale genetic microstructures among Sino-Tibetan speakers. Finally, natural-selection signals revealed via iHS, nSL and iHH12 showed natural selection signatures associated with disease susceptibility in Sherpas. Generally, we provided the comprehensive landscape of admixture and evolutionary history of Sherpa people based on the shared alleles and haplotypes from the InDel-based genotype data and high-density genome-wide SNP data. The more detailed genetic landscape of Sherpa people should be further confirmed and characterized via ancient genomes or single-molecule real-time sequencing technology.

PMID:34826721 | DOI:10.1016/j.fsigen.2021.102633