Category: Statistics

Neurourol Urodyn. 2021 Jul 5. doi: 10.1002/nau.24740. Online ahead of print.

ABSTRACT

AIM: To compare the efficacy of the treatment with transcutaneous perineal electrostimulation versus intracavitary electrostimulation to reduce the frequency of urinary incontinence after radical prostatectomy and the impact on the quality of life (QoL).

METHODS: This single-blind equivalence-randomized controlled trial equally (1:1) randomly allocated men with urinary incontinence post radical prostatectomy into surface electrodes perineal group (intervention group, IG) and intra-anal probe group (control group, CG). Outcomes included changes in the 24h-Pad Test (main variable), and ICIQ-SF (International Consultation on Incontinence Questionnaire Short-Form), SF-12 (Short Form Health Survey), and I-QOL (incontinence quality of life questionnaire) questionnaires. Clinical data were collected at baseline, 6 and 10 weeks. For the comparisons between variables, χ² test and Student’s t test were used. Equivalence was analyzed by estimating the mean change (90% confidence interval) of urinary incontinence based on the Pad Test. The analysis was performed for the per-protocol and the intention-to-treat populations. Statistical significance level was set at p < 0.05.

RESULTS: Seventy patients were included, mean age 62.8 (SD 9.4) years. Mean baseline 24h-Pad Test was 328.3 g (SD 426.1) and a significant decrease (p < 0.001) in the grams of urine loss at 5 weeks (159.1 g in the IG and 121.7 g in the CG), and at 10 weeks of treatment (248.5 g in the IG and 235.8 g in the CG) was observed. However, the final difference in the grams of urine loss between both treatments showed the absence of statistical significance (p = 0.874). In both groups, the ICIQ-SF, I-QOL, and SF-12 questionnaires revealed a significant improvement in QoL.

CONCLUSION: Surface and intra-anal electrostimulation treatments reduced significantly losses of urine, but differences in grams of urine loss throughout the therapy between groups were not significant, suggesting that the efficacy of the two treatments is not statistically different. Nonetheless, the improvement observed in both groups was statistically significant and clinically relevant.

PMID:34224598 | DOI:10.1002/nau.24740

Spine (Phila Pa 1976). 2021 Jul 1. doi: 10.1097/BRS.0000000000004159. Online ahead of print.

ABSTRACT

STUDY DESIGN: Retrospective, randomized, radiographic study assessing age-related changes (ARCs) on lumbar magnetic resonance imaging (MRI) using an ensemble method.

OBJECTIVES: This study proposed to develop a novel reporting method to calculate a predicted “age estimate” for the ARC seen on lumbar MRI.

SUMMARY OF BACKGROUND DATA: Lumbar MRI reports include pathological findings but usually not the prevalence data of common findings which has been shown to decrease the need for narcotics in the management of non-specific lower back pain (NSLBP). Comparing the normal age estimation for lumbar spine degenerative changes/ARC on MRI and comparing this to the patient’s real age may improve patient outcome in the management of NSLBP.

METHODS: A total of 60 lumbar MRI were taken from patients aged between 0 and 100 years. Lumbar MRI features reported as associated with age on review of the literature were measured on each MRI and statistically evaluated for correlation with age. Factors found to be associated were then entered into an ensemble model consisting of several machine learning techniques. The resulting ensemble model was then tested to predict age for a further 10 random lumbar MRI scans. One further lumbar MRI was then assessed for observer variability.

RESULTS: Features that correlated with age were disc signal intensity, the appearance of paravertebral and psoas muscle, disc height, facet joint size, ligamentum flavum thickness, Schmorl nodes, Modic changes, vertebral osteophytes, and high-intensity zones. With the ensemble model, 80% of estimated spinal age were within 11 years of the subjects’ physical age.

CONCLUSION: It would appear that the intervertebral discs, and many other structures that are subjected to loading in and around the lumbar spine change their lumbar MRI appearance in a predictable way with increasing age. ARC on lumbar MRI can be assessed to predict an “expected age” for the subject.Level of Evidence: 2.

PMID:34224512 | DOI:10.1097/BRS.0000000000004159

J Strength Cond Res. 2021 Jun 30. doi: 10.1519/JSC.0000000000004086. Online ahead of print.

ABSTRACT

Szyszka, P and Czaplicki, A. Analysis of record scores in the clean and its variations in the long-term training of young weightlifters. J Strength Cond Res XX(X): 000-000, 2021-The main objectives of this study were to determine the time trajectories of record scores in the clean lift (C) and its derivatives achieved by young weightlifters in a 2-year training cycle and to estimate the quantitative relationships between these scores. The study involved 17 weightlifters who were tested 7 times at 3-month intervals. The computations were based on an individual growth curve approach. The study found statistically significant increases (p < 0.05) in record scores between consecutive measurements until the last measurement for the hang clean (HC), the second to last measurement for the C, and the fourth measurement for the power clean (PC) and the hang power clean (HPC). The overall mean ratios of the record scores in the C to those in the HC, PC, and HPC were approximately constant and amounted to 0.96, 0.89, and 0.80, respectively. Statistically significant differences (p < 0.05) between individual time trajectories of record scores in the C and its derivatives were also identified in the 2 consecutive annual training macrocycles. The results suggest that the long-term analysis of record scores in the C and its derivatives can be useful in assessing athletes’ sport level, in predicting their performance, and in proper exercise selection in the training of young weightlifters.

PMID:34224507 | DOI:10.1519/JSC.0000000000004086

J Glaucoma. 2021 Jul 1. doi: 10.1097/IJG.0000000000001907. Online ahead of print.

ABSTRACT

PURPOSE: To evaluate the effectiveness of bacterial cellulose membrane (BCM) in preventing fibrosis in trabeculectomy and the biocompatibility of BCM with conjunctiva and sclera.

METHODS: Twenty-one eyes of 21 adult rabbits underwent fornix-based trabeculectomy. Standard surgery was done to control group (CG, n=7). Mitomycin-C (0.3▒mg/mL, 3▒min) was applied to MMC group only (MMCG, n=7). BCM (~100▒µm thick,10×10▒mm,single layer) was covered on the sclerotomy area before conjunctiva was closed in BCM group (BCMG, n=7). Intraocular pressures (IOP) were measured before, and 7, 14, 28 and 45 days after surgery (IOP-POD7,POD14,POD28,POD45). The IOP decrease were expressed as DIOP%-POD7, DIOP%-POD14,DIOP%-POD28 and DIOP%-POD45. The rabbits were sacrificed on the 45th day. Conjunctival vessel (CV) number, degrees of fibrosis, total inflammation, foreign body reaction (FBR), inflammatory cell types (B-cells,T-cells,plasma cells, macrophages, bleb spaces and the expression of α-smooth muscle actin(α-SMA) were studied using histopathology and immunohistochemistry techniques. The groups were compared using nonparametric tests.

RESULTS: There was no statistically significant difference between the groups regarding baseline IOP and DIOP%-POD7 (P>0.05). While DIOP%-POD14, 28 and 45 were similar between BCMG and MMCG, they were significantly lower in CG (P<0.05). The lowest CV number was detected in the MMCG but the difference was not significant. There was no difference between BCMG and CG with regard to the numbers of B-cells, T-cells and macrophages, however these cells were significantly lower in MMCG (P<0.05). Five cases had mild and 2 cases had moderate FBR in the BCMG. There was mild to moderate inflammation in all BCM cases. While fibrosis and α-SMA staining were higher in the CG (P<0.001), they were minimal in the BCM and MMC groups.

CONCLUSIONS: BCM showed good biocompatibility and provided better control of IOP with minimal fibrosis in trabeculectomy site compared to the control group.

PMID:34224487 | DOI:10.1097/IJG.0000000000001907

J Pediatr Gastroenterol Nutr. 2021 Jun 28. doi: 10.1097/MPG.0000000000003220. Online ahead of print.

ABSTRACT

OBJECTIVE: Cannabis Hyperemesis Syndrome (CHS) is characterized by recurrent episodes of intractable emesis associated with heavy use of cannabis. Recognition of CHS can be problematic due to the lack of specific biomarkers, which can point the clinician to the diagnosis. We present, retrospectively, a series of adolescent/young adult patients who presented to a pediatric gastroenterology (GI) service with acute on chronic nausea and vomiting, subsequently found to have CHS with associated elevated urinary cannabis metabolite concentrations.

METHODS: We describe 15 patients referred to our pediatric GI division for intractable emesis with spot urinary cannabis metabolite carboxy-THC (THC-COOH) concentrations from January 1, 2018 through April 20, 2019. Urinary testing was performed using gas chromatography mass spectrometry (GC-MS) in a manner consistent with CLIA requirements at Mayo Clinic laboratory (Rochester, MN). The laboratory cutoffs were 3.0 ng/mL. Data was extracted via chart review and analyzed via online statistical application.

RESULTS: Fifteen patients (7 females, 8 males) were studied with an average age of 17.7 years. All patients reported frequent cannabis use for at least 1 month and exhibited intractable, non-bilious emesis for at least 2 weeks. Twelve patients also reported weight loss. Two patients had underlying gastrointestinal disease (one with Crohn’s Disease and one with irritable bowel syndrome). All patients had essentially normal GI workup including laboratory tests, imaging studies and endoscopies.Fourteen of 15 patients had urinary THC-COOH concentrations > 100ng/mL, with 7 individuals exhibiting levels > 500ng/mL. One patient had a urinary TCH-COOH concentration level under 100ng/mL had not used cannabis for 2 weeks. Most other patients had used cannabis within 2 days of providing a urine sample. The Binomial test for CHS patients with urinary THC-COOH levels over 100ng/mL was significant with a p-value of < 0.0005 (one tail test).

CONCLUSION: Cannabis Hyperemesis Syndrome is associated with an elevated urinary THC-COOH level usually exceeding 100ng/mL, which is indicative of significant chronic cannabis exposure. In patients with a history consistent with CHS, urine THC-COOH testing may help guide the diagnostic evaluation of these patients and decrease the need for further workup.

PMID:34224490 | DOI:10.1097/MPG.0000000000003220

Pain. 2021 Jun 29. doi: 10.1097/j.pain.0000000000002385. Online ahead of print.

ABSTRACT

Quantitative Sensory Testing (QST) can be useful to identify high-risk patients for the development of chronic postsurgical pain (CPSP). This systematic review aims to assess if presurgical sensory sensitivity measured using QST is associated with acute and CPSP after total joint arthroplasty.A systematic search was performed in Sep/2020 in PubMed, EMBASE, Web of Science and Scopus, using terms related to total joint arthroplasty and QST. Prospective studies were included if they reported an association between presurgical QST and postsurgical pain in adults with osteoarthritis undergoing primary unilateral total joint arthroplasty.From 2994 identified studies, 18 met the inclusion criteria (1869 patients). Total knee arthroplasty was the most common surgery (16 studies) and pressure pain threshold (PPT) was the most common test (11 studies), followed by dynamic measures (9 studies). Postsurgical pain was assessed at acute (5 studies), subacute (2 studies) and chronic (13 studies) time points. Risk of bias was assessed using the Quality in Prognosis Studies Tool, and evaluated as low-to-moderate in most domains. Fourteen studies reported at least one statistically significant association between QST and pain (acute: 4 studies, subacute: 1 study, chronic: 9 studies). PPT was associated with postsurgical pain in 6 studies (out of 11, 55%), heat pain threshold in 2 (out of 6, 33%), conditioned pain modulation in 1 (out of 6, 17%) and temporal summation of pain in 5 (out of 8, 63%). The predictive role of presurgical QST for post-arthroplasty pain remains unclear, mainly due to heterogeneous methodologies and inconsistent results.

PMID:34224493 | DOI:10.1097/j.pain.0000000000002385

J Cataract Refract Surg. 2021 Jun 28. doi: 10.1097/j.jcrs.0000000000000734. Online ahead of print.

ABSTRACT

PURPOSE: To investigate the accordance and repeatability of tomographic parameters measured by a novel Swept-Source optical coherence tomographer (SS-OCT, ANTERION), a rotating Scheimpflug camera (RSC, Pentacam) and a dual Scheimpflug-Placido system (DSP, Galilei G6).

SETTING: Department of Ophthalmology of Univ. Hospital Carl Gustav Carus, Dresden, Germany.

DESIGN: Prospective reliability analysis.

METHODS: Thirty randomly selected eyes of 30 healthy participants were enrolled in this study. Normal tomography were ensured by bilaterally evaluating appropriated parameters using RSC. All subjects received three consecutive measurements on each device by the same operator and in the uniform order RSC, SS-OCT and DSP. Anterior (ACP) and posterior (PCP) corneal parameters such as flat and steep keratometry and corneal thickness were analyzed. Repeatability was assessed by using a coefficient of repeatability (CR) and a coefficient of variation (CV). Agreement between RSC and SS-OCT as well as RSC and DSP were shown by Bland-Altman plots (BA).

RESULTS: CR of ACP did not exceed 0.5 D. There were no statistical differences in repeatability of ACP obtained from the three devices (P>0.05). For PCP and corneal thickness there was statistically significant higher repeatability mostly found for SS-OCT as opposed to RSC and DSP (P<0.05). For a wide range of analyzed parameters there were large limits of agreement (95%-LoA) found between the devices.

CONCLUSION: The SS-OCT showed highly repeatable measurements in healthy subjects regarding anterior, posterior and corneal thickness parameters. Repeatability of ACP did not differ between the devices. A mostly wide range of 95%-LoA prevents interchangeability between the devices.

PMID:34224476 | DOI:10.1097/j.jcrs.0000000000000734

J Cataract Refract Surg. 2021 Jun 28. doi: 10.1097/j.jcrs.0000000000000737. Online ahead of print.

ABSTRACT

PURPOSE: To compare corneal endothelial damage from longitudinal and torsional ultrasound during phacoemulsification.

SETTING: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

DESIGN: Experimental Study.

METHODS: Nine New Zealand white rabbits underwent bilateral surgery. After incision, the Intrepid Balanced tip of the Centurion (Alcon) Ozil handpiece was inserted into the anterior chamber and the following settings were used: 50 mL/minute flow, 70 mmHg intraocular pressure, 600 mmHg vacuum, and 60% longitudinal (one eye) or torsional (contralateral eye) ultrasound for 30 seconds. Cumulative dissipated energy (CDE) was noted. After euthanasia and enucleation, the corneas were removed, stained with trypan blue/alizarin red, and photographed (X400 photographs from 5 specific areas, and 1 overview photograph from each corneal button). The ImageJ program was used to evaluate cell damage and loss in the photographs obtained from each cornea.

RESULTS: Cavitation bubbles around the phaco tip was generally observed in the longitudinal group. CDE was 17.4 +/- 0.58 and 6.93 +/- 0.15 in the longitudinal and torsional groups, respectively (P = 0.003). The percentage of intact cells was statistically higher in the torsional group, and the percentage of lost cells was statistically higher in the longitudinal group (P = 0.003). This was observed in the analysis of the X400 photographs, as well as the overview photographs.

CONCLUSION: This study suggests that torsional ultrasound was associated with significantly less corneal endothelial cell damage than classical longitudinal tip motion, providing further insight on mechanisms of corneal endothelial damage during phacoemulsification.

PMID:34224479 | DOI:10.1097/j.jcrs.0000000000000737

J Cardiovasc Nurs. 2021 Jul 1. doi: 10.1097/JCN.0000000000000832. Online ahead of print.

ABSTRACT

BACKGROUND: Mental distress is reported internationally among patients with cardiac disease. A Danish survey found that 25% of patients with cardiac disease experienced symptoms indicating anxiety and that anxiety was associated with an increased risk of death.

AIM: The aims of this study were to (1) compare cause of death patterns among deceased cardiac patients with anxiety to those without anxiety and (2) examine the association between anxiety symptoms and specific causes of death.

METHODS: We used data from the DenHeart survey to evaluate symptoms of anxiety at discharge by using the Hospital Anxiety and Depression Scale. Data on mortality in the 3 years after discharge and cause of death according to International Classification of Diseases-10 classification came from national registers. Cause of death was compared between patients with and without anxiety using χ2 tests. The association between symptoms of anxiety and cause of death was investigated using logistic regression.

RESULTS: Of 12 913 patients included, a total of 1030 (8%) died within 3 years. After 1 year, 4% of patients with anxiety symptoms had died versus 2% of patients without; after 3 years, the proportions were 9% versus 8%, respectively. Almost all died of natural causes irrespective of anxiety symptoms. No statistically significant differences were found regarding the cause of death between patients with and without anxiety.

CONCLUSION: Despite higher mortality rates in patients with cardiac disease with anxiety symptoms, the pattern of cause of death was identical for patients with cardiac disease with and without anxiety symptoms. It seems that an acceleration of morbid processes leading to mortality is more likely than a difference in cause of death. However, further research is needed to better understand the behavioral and pathophysiological processes that cause the higher mortality seen among patients reporting symptoms of anxiety.

PMID:34224466 | DOI:10.1097/JCN.0000000000000832

Epidemiology. 2021 Jun 24. doi: 10.1097/EDE.0000000000001381. Online ahead of print.

ABSTRACT

Quantitative bias analyses allow researchers to adjust for uncontrolled confounding, given specification of certain bias parameters. When researchers are concerned about unknown confounders, plausible values for these bias parameters will be difficult to specify. Ding and VanderWeele developed bounding factor and E-value approaches that require the user to specify only some of the bias parameters. We describe the mathematical meaning of bounding factors and E-values as well as the plausibility of these methods in an applied context. We encourage researchers to pay particular attention to the assumption made, when using E-values, that the prevalence of the uncontrolled confounder among the exposed is 100% (or, equivalently, the prevalence of the exposure among those without the confounder is 0%). We contrast methods that attempt to bound biases or effects and alternative approaches such as quantitative bias analysis. We provide an example where failure to make this distinction led to erroneous statements. If the primary concern in an analysis is with known but unmeasured potential confounders, then E-values are not needed and may be misleading. In cases where the concern is with unknown confounders, the E-value assumption of an extreme possible prevalence of the confounder limits its practical utility.

PMID:34224472 | DOI:10.1097/EDE.0000000000001381