How Do We Determine if a Correlation Between Two Continuous Variables Is Statistically Significant?

OBJECTIVEForamen ovale electrodes (FOEs) are a minimally invasive method to localize mesial temporal seizures in cases in which noninvasive methods are inconclusive. The objective of this study was to identify factors predicting the ability of FOEs to yield a diagnosis in order to determine optimal candidates for this procedure.METHODSAll cases of diagnostic investigations performed with FOEs at the authors’ institution between 2005 and 2017 were reviewed. FOE investigation was defined as diagnostic if it led to a treatment decision. Demographic and clinical variables for diagnostic and nondiagnostic investigations were compared using a Wilcoxon rank-sum test for continuous variables and Fisher’s exact test for categorical variables.RESULTSNinety-three patients underwent investigations performed with FOEs during the study period and were included in the study. FOE investigation was diagnostic in 75.3% of cases. Of patients who underwent anterior temporal lobectomy following diagnostic FOE evaluation, 75.9% were Engel class I at last follow-up (average 40.1 months). When the diagnostic and nondiagnostic FOE groups were compared, patients who had diagnostic investigations were more likely to be male (57.1% male vs 26.1% in the nondiagnostic group, p = 0.015). They were also more likely to have temporal lesions on preoperative MRI (p = 0.018).CONCLUSIONSFOEs are a useful, minimally invasive diagnostic modality resulting in a treatment decision in 75% of cases. Male patients and patients with temporal lesions on MRI may be most likely to benefit from FOE investigation.

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Faculty Opinions recommendation of Natural history of imatinib-naive GISTs: a retrospective analysis of 929 cases with long-term follow-up and development of a survival nomogram based on mitotic index and size as continuous variables.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.13356067.14726207 ◽

2011 ◽

Author(s):

Richard Riedel

Keyword(s):

Natural History ◽

Retrospective Analysis ◽

Mitotic Index ◽

Continuous Variables ◽

Long Term Follow Up ◽

History Of

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GCS-Pupil Score Has a Stronger Association with Mortality and Poor Functional Outcome than GCS Alone in Pediatric Severe Traumatic Brain Injury

Pediatric Neurosurgery ◽

10.1159/000517330 ◽

2021 ◽

pp. 1-8

Author(s):

Binod Balakrishnan ◽

Heather VanDongen-Trimmer ◽

Irene Kim ◽

Sheila J. Hanson ◽

Liyun Zhang ◽

...

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Functional Outcome ◽

Cerebral Performance Category ◽

Regression Tree ◽

Classification And Regression Tree ◽

Continuous Variables ◽

Poor Functional Outcome ◽

Severity Scores ◽

Pupil Reactivity

Background: The Glasgow Coma Scale (GCS), used to classify the severity of traumatic brain injury (TBI), is associated with mortality and functional outcomes. However, GCS can be affected by sedation and neuromuscular blockade. GCS-Pupil (GCS-P) score, calculated as GCS minus Pupil Reactivity Score (PRS), was shown to better predict outcomes in a retrospective cohort of adult TBI patients. We evaluated the applicability of GCS-P to a large retrospective pediatric severe TBI (sTBI) cohort. Methods: Admissions to pediatric intensive care units in the Virtual Pediatric Systems (VPS, LLC) database from 2010 to 2015 with sTBI were included. We collected GCS, PRS (number of nonreactive pupils), cardiac arrest, abusive head trauma status, illness severity scores, pediatric cerebral performance category (PCPC) score, and mortality. GCS-P was calculated as GCS minus PRS. χ2 or Fisher’s exact test and Mann-Whitney U test compared categorical and continuous variables, respectively. Classification and regression tree analysis identified thresholds of GCS-P and GCS along with other independent factors which were further examined using multivariable regression analysis to identify factors independently associated with mortality and unfavorable PCPC at PICU discharge. Results: Among the 2,682 patients included in the study, mortality was 23%, increasing from 4.7% for PRS = 0 to 80% for PRS = 2. GCS-P identified more severely injured patients with GCS-P scores 1 and 2 who had worse outcomes. GCS-P ≤ 2 had higher odds for mortality, OR = 68.4 (95% CI = 50.6–92.4) and unfavorable PCPC, OR = 17.3 (8.1, 37.0) compared to GCS ≤ 5. GCS-P ≤ 2 also had higher specificity and positive predictive value for both mortality and unfavorable PCPC compared to GCS ≤ 5. Conclusions: GCS-P, by incorporating pupil reactivity to GCS scoring, is more strongly associated with mortality and poor functional outcome at PICU discharge in children with sTBI.

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Small Choroidal Melanoma: Correlation of Growth Rate with Pathology

Ocular Oncology and Pathology ◽

10.1159/000517203 ◽

2021 ◽

pp. 1-10

Author(s):

Vishal Raval ◽

Shiming Luo ◽

Emily C. Zabor ◽

Arun D. Singh

Keyword(s):

Growth Rate ◽

Retinal Pigment ◽

Choroidal Melanoma ◽

Case Series ◽

Subretinal Fluid ◽

Categorical Variables ◽

Continuous Variables ◽

Basal Diameter ◽

Orange Pigment ◽

Rpe Atrophy

Purpose: The aim of the study was to evaluate equivalence of growth rate and pathologic confirmation in small choroidal melanoma (SCM). Design: This study is a case series. Subjects, Participants, and Controls: A total of 61 patients with a choroidal melanocytic tumor of size 5.0–16.0 mm in the largest basal diameter and 1.0–2.5 mm in thickness were classified into the pathology-confirmed group (n = 19), growth-confirmed group (n = 30), and with combined observations (n = 12). Methods: Distribution of clinical variables (age, gender, laterality, tumor dimensions, tumor location, and presence of orange pigment, subretinal fluid, drusen, and retinal pigment epithelial [RPE] atrophy) between the groups was analyzed. Patient and disease characteristics were summarized as the median and interquartile range for continuous variables and the frequency and percentage for categorical variables. Comparisons were made using the Wilcoxon rank sum test for continuous variables and either Fisher’s exact test or the χ2 test for categorical variables with a p value threshold of 0.05 for statistical significance. Growth rate (change in basal dimension/12 months) diagnostic of SCM was quantified. Main Outcome Measures: The primary aim of this study was to test the hypothesis that “growth” was diagnostic of SCM with the secondary aim of quantifying the malignant “growth rate” (growth rate of SCM). Results: The clinical characteristics among all 3 groups were similar except more patients with symptoms (68 vs. 20 vs. 42%, p = 0.004) and juxtapapillary location (p = 0.03) were in the pathology group than in the growth-confirmed group. Those in the combined and growth-confirmed groups had more patients with drusen (11 vs. 60 vs. 50%, p = 0.003) and RPE atrophy (11 vs. 23 vs. 67%, p = 0.003), respectively, than in the pathology group. The median time to detect growth was 9 months (range 3–26 months). The mean growth rate in basal dimension was 1.8 mm/12 months (range, 0.0–7.4 mm; [95% CI: 1.32–2.28]). Conclusions and Relevance: Choroidal melanocytic lesions exhibiting a defined growth rate can be clinically diagnosed as SCM without a need for biopsy.

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Comparative Morbidity Profile of Elective vs Therapeutic Neck Dissection

Otolaryngology ◽

10.1177/01945998211008915 ◽

2021 ◽

pp. 019459982110089

Author(s):

Quinn Dunlap ◽

James Reed Gardner ◽

Amanda Ederle ◽

Deanne King ◽

Maya Merriweather ◽

...

Keyword(s):

Neck Dissection ◽

Surgical Complications ◽

Chart Review ◽

Care Center ◽

Tertiary Care ◽

Retrospective Chart Review ◽

Neck Surgery ◽

Continuous Variables ◽

Significant Difference ◽

History Of

Objective Neck dissection (ND) is one of the most commonly performed procedures in head and neck surgery. We sought to compare the morbidity of elective ND (END) versus therapeutic ND (TND). Study Design Retrospective chart review. Setting Academic tertiary care center. Methods Retrospective chart review of 373 NDs performed from January 2015 to December 2018. Patients with radical ND or inadequate chart documentation were excluded. Demographics, clinicopathologic data, complications, and sacrificed structures during ND were retrieved. Statistical analysis was performed with χ2 and analysis of variance for comparison of categorical and continuous variables, respectively, with statistical alpha set a 0.05. Results Patients examined consisted of 224 males (60%) with a mean age of 60 years. TND accounted for 79% (n = 296) as compared with 21% (n = 77) for END. Other than a significantly higher history of radiation (37% vs 7%, P < .001) and endocrine pathology (34% vs 2.6%, P < .001) in the TND group, no significant differences in demographics were found between the therapeutic and elective groups. A significantly higher rate of structure sacrifice and extranodal extension within the TND group was noted to hold in overall and subgroup comparisons. No significant difference in rate of surgical complications was appreciated between groups in overall or subgroup analysis. Conclusion While the significantly higher rate of structure sacrifice among the TND population represents an increased morbidity profile in these patients, no significant difference was found in the rate of surgical complications between groups. The significant difference seen between groups regarding history of radiation and endocrine pathology likely represents selection bias.

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The combined impact of Type D personality and depression on cardiovascular events after acute myocardial infarction

Psychological Medicine ◽

10.1017/s0033291721002932 ◽

2021 ◽

pp. 1-11

Author(s):

Yini Wang ◽

Xueqin Gao ◽

Zhenjuan Zhao ◽

Ling Li ◽

Guojie Liu ◽

...

Keyword(s):

Risk Factors ◽

Myocardial Infarction ◽

Acute Myocardial Infarction ◽

Significant Risk ◽

Type D Personality ◽

Adverse Outcomes ◽

Combined Effect ◽

Continuous Variables ◽

Type D

Abstract Background Type D personality and depression are the independent psychological risk factors for adverse outcomes in cardiovascular patients. The aim of this study was to examine the combined effect of Type D personality and depression on clinical outcomes in patients suffering from acute myocardial infarction (AMI). Methods This prospective cohort study included 3568 patients diagnosed with AMI between February 2017 and September 2018. Type D personality and depression were assessed at baseline, while the major adverse cardiac event (MACE) rate (cardiac death, recurrent non-fatal myocardial infarction, revascularization, and stroke) and in-stent restenosis (ISR) rate were analyzed after a 2-year follow-up period. Results A total of 437 patients developed MACEs and 185 had ISR during the follow-up period. The Type D (+) depression (+) and Type D (+) depression (−) groups had a higher risk of MACE [95% confidence interval (CI) 1.74–6.07] (95% CI 1.25–2.96) and ISR (95% CI 3.09–8.28) (95% CI 1.85–6.22). Analysis of Type D and depression as continuous variables indicated that the main effect of Type D, depression and their combined effect were significantly associated with MACE and ISR. Moreover, Type D (+) depression (+) and Type D (+) depression (−) emerged as significant risk factors for MACE and ISR in males, while only Type D (+) depression (+) was associated with MACE and ISR in female patients. Conclusions These findings suggest that patients complicated with depression and Type D personality are at a higher risk of adverse cardiovascular outcomes. Individual assessments of Type D personality and depression, and comprehensive interventions are required.

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Whole blood chromium concentration is very rarely elevated independently of whole blood cobalt

Scientific Reports ◽

10.1038/s41598-021-91512-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Olli Lainiala ◽

Mari Karsikas ◽

Aleksi Reito ◽

Antti Eskelinen

Keyword(s):

Whole Blood ◽

Cost Savings ◽

Chromium Concentration ◽

Continuous Variables ◽

Metal Debris ◽

Screening Guidelines ◽

Metal On Metal ◽

Hip Replacements

AbstractDue to the risk of adverse reactions to metal debris resulting from increased wear of the arthroplasty more than one million metal-on-metal (MoM) hip replacements worldwide are in active follow-up. Follow-up usually includes measurement of both whole blood cobalt (Co) and chromium (Cr) concentrations. Our experience is that Cr is seldom independently elevated. We wanted to ascertain whether blood Cr measurements could be omitted from follow-up protocols without lowering the quality of follow-up. We identified 8438 whole blood Co and Cr measurements performed without or prior to revision surgery. When the cut-off levels 5 µg/L and 7 µg/L were used, Cr was independently elevated in only 0.5% (95% confidence interval, CI, 0.3 to 0.6) and 0.2% (CI 0.1 to 0.3) of the measurements. The models with continuous variables showed that the higher the blood metal concentrations are the lower the percentage of measurements with Cr higher than Co. Our results suggest that whole blood Cr is very rarely independently elevated and therefore the authorities should consider omitting Cr measurements from their screening guidelines of MoM hip replacements. We believe this change in practice would simplify follow-up and lead to cost savings without decreasing the quality of follow-up.

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