Stepping-up accurate quantification of chlorinated paraffins: Successful certification of the first matrix reference material.

BACKGROUND: Chlorinated paraffins (CPs) are industrial chemicals categorised as persistent organic pollutants because of their toxicity, persistency and tendency to long-range transport, bioaccumulation and biomagnification. Despite having been the subject of environmental attention for decades, analytical methods for CPs still struggle reaching a sufficient degree of accuracy. Among the issues negatively impacting the quantification of CPs, the unavailability of well-characterised standards, both as pure substances and as matrix (certified) reference materials (CRMs), has played a major role. The focus of this study was to provide a matrix CRM as quality control tool to improve the comparability of CPs measurement results. RESULTS: We present the process of certification of ERM®-CE100, the first fish reference material assigned with certified values for the mass fraction of short-chain and medium-chain chlorinated paraffins (SCCPs and MCCPs, respectively). The certification was performed in accordance with ISO 17034:2016 and ISO Guide 35:2017, with the value assignment step carried out via an intercomparison of laboratories of demonstrated competence in CPs analysis and applying procedures based on different analytical principles. After confirmation of the homogeneity and stability of the CRM, two certified values were assigned for SCCPs, depending on the calibrants used: 31 ± 9 µg kg-1 and 23 ± 7 µg kg-1. The MCCPs certified value was established as 44 ± 17 µg kg-1. All assigned values are relative to wet weight in the CRM that was produced as a fish paste to enhance similarity to routine biota samples. SIGNIFICANCE AND NOVELTY: The fish tissue ERM-CE100 is the first matrix CRM commercially available for the analysis of CPs, enabling analytical laboratories to improve the accuracy and the metrological traceability of their measurements. The certified CPs values are based on results obtained by both gas and liquid chromatography coupled with various mass spectrometric techniques, offering thus a broad validity to laboratories employing different analytical methods and equipment.

Prevalence and socio-demographic correlates of multi-modal cannabis use among young adults who currently use cannabis.

Cannabis use is common in young adulthood, yet little is known about the prevalence and patterns of multi-modal (i.e., use of more than one mode) cannabis use. Objective: We aimed to (1) determine the past 30-day prevalence of five modes (smoke, vape, edible, dab, other) of cannabis use, (2) describe the prevalence of multi-modal cannabis use (single vs. dual vs. poly-modal), and (3) identify socio-demographic correlates of multi-modal use among young adults. Method: Participants were 764 22-30-year-olds who currently used cannabis from Wave 9 (Spring 2019) of the Marketing and Promotions Across Colleges in Texas Project. Participants were 25.11 years old on average (SD = 1.81), 63.6% female, 38.7% identified as non-Hispanic white, 30.6% as Hispanic/Latino, 13.0% as Asian and 9.4% as Black, and 8.2% identified with two or more races or another race/ethnicity. Bivariate analyses and a multinomial regression were used to examine study questions. Results: Smoking was the most common mode of cannabis use followed by vaping and then edibles. Nearly 43% of participants reported single-modal cannabis use, 33% reported dual-modal use, and 24% reported poly-modal use. Males and those identifying as non-heterosexual were at a greater risk than their counterparts for using multiple modes of cannabis. Participants identifying as Black were at a reduced risk for poly-modal compared to single-modal use. Conclusion: Multi-modal use is common among young adults who currently use cannabis, indicating a need for universal efforts aimed at all young adults. Tailored interventions aimed toward those at elevated risk for multi-modal use also are needed.

Factors predictive of recurrence, metastasis and death in node-negative penile squamous cell carcinoma: A retrospective multicentre cohort study.

BACKGROUND: Penile squamous cell carcinoma (PSCC) carries significant morbidity and mortality. Literature is limited regarding prognostic factors, especially prognostic factors for development of metastasis. OBJECTIVES: To identify independent prognostic factors associated with poor outcomes, defined as local recurrence (LR), metastasis and disease-specific death (DSD) in clinically node-negative PSCC undergoing local therapy. METHODS: Thirty-two-year Retrospective Multicenter Cohort Study of 265 patients with histologically diagnosed PSCC at three tertiary care centres. Predictive models based on patient or tumour characteristics were developed. RESULTS: Local recurrence occurred in 56 patients, metastasis in 52 patients and DSD in 40 patients. In multivariable models, the following five factors were independent prognostic factors based on subhazard ratio (SHR): history of balanitis (LR SHR: 2.3; 95% CI 1.2-4.2), poor differentiation (metastasis SHR 1.9; 95% CI 1.0-3.6), invasion into the corpora (metastasis SHR: 3.0; 95% CI 1.5-5.8 and DSD SHR: 4.5; 95% CI 1.7-12.1), perineural invasion (PNI) (metastasis SHR: 2.8; 95% CI 1.4-5.5 and DSD SHR: 3.5; 95% CI, 1.6-7.8) and a history of phimosis (DSD SHR: 2.5; 95% CI 1.2-5.3). The 5-year cumulative incidence of metastasis was higher for tumours with PNI [cumulative incidence function (CIF) = 55%, 95% CI 38-75 vs. CIF 15%, 95% CI 11-22], corporal invasion (CIF: 35%, 95% CI 26-47 vs. 12%, 95% CI 7-19) and poorly differentiated tumours (CIF = 46%, 95% CI 31-64 vs. CIF 15%, 95% CI 11-22). CONCLUSIONS: History of balanitis, history of phimosis, PNI, corporal invasion and poor differentiation are independent risk factors associated with poor outcomes. Since poor differentiation and PNI currently constitute only T1b disease, prognostic staging can likely be improved.

Comparing the number of outdoor sugar-sweetened beverage and caffeinated beverage advertisements near schools by school type and school-level economic advantage.

INTRODUCTION: Sugar-sweetened beverage and caffeinated beverage consumption are associated with a variety of health issues among youth. Food and beverage marketing has been shown to affect youth's preferences, purchases, and consumption of marketed products. Previous research suggests that outdoor food and beverage marketing differs by community demographics, with more advertisements in lower-income communities and near schools. The purpose of this study is to examine the density of sugar-sweetened and caffeinated beverage advertisements near schools by school type (middle vs. high school) and by school-level SES. METHODS: Data are from the Outdoor Measuring and Evaluating the Determinants and Influence of Advertising (MEDIA)study, which documented and described all outdoor food and beverage advertisements near 47 middle and high schools in 2012. Beverage advertisements were categorized as: sugar-sweetened/caffeinated, sugar-sweetened/non-caffeinated, non-sugar-sweetened/caffeinated, or non-sugar-sweetened/non-caffeinated. Schools were categorized by type (middle vs high) and by SES as determined by the percentage of students qualifying for free or reduced-price lunch. Bootstrapped non-parametric Mann-Whitney U tests compared the number of advertisements in each category by school type and school-level SES (higher vs lower). RESULTS: Compared to schools with higher SES, schools with lower SES had significantly more advertisements for sugar-sweetened/non-caffeinated beverages (Medianlow = 28.5 (IQR 17-69), vs Medianhigh = 10.5 (IQR 4-17) (p = 0.002)., sugar-sweetened non-caffeinated (Medianlow = 46 (IQR 16-99) vs Medianhigh = 13.5 (IQR 6-25), p = 0.002), -sugar-sweetened caffeinated (Medianlow = 12 (IQR 8-19) vs Medianhigh = 6 (IQR 2-8), p = 0.000), and non-sugar-sweetened non-caffeinated (Medianlow = 30 (IQR 13-65) vs Medianhigh = 14 (IQR 4-29), p = 0.045).There were no significant differences by school type. CONCLUSION: This study adds to the literature demonstrating pervasive marketing of unhealthy products in lower-income communities. Disproportionate exposure to sugar-sweetened and caffeinated beverage advertisements in lower-income communities may contribute to the disparities in associated health outcomes by economic status.

Characterization of Thyroid Cancer among Hispanics in California, USA, from 2010 to 2020.

BACKGROUND: Previous studies on Hispanic thyroid cancer cases show sex disparities and an increased prevalence of large tumor sizes and nodal involvement. Here, we characterized Hispanic thyroid cancer cases in California. METHODS: We identified thyroid cancer cases from 2010 to 2020 using the California Cancer Registry by sex, race/ethnicity, histology, TNM stage, tumor size, lymph node involvement, and Charlson comorbidity score. The age-adjusted incidence rate (AAIR) and age-adjusted mortality rate (AAMR) for all causes of death were calculated. A Cox proportional hazards regression analysis was performed to evaluate the mortality risk from all causes of death by race. RESULTS: Overall, 56,838 thyroid cancer cases were identified, including 29.75% in Hispanics. Hispanics had the highest female-to-male incidence rate ratio (IRR 3.54) and the highest prevalence of T3/T4 tumor size (28.71%), the highest N1 nodal status (32.69%), and the highest AAMR (0.79 per 100,000 people). After adjusting for demographic and tumor covariates, compared to non-Hispanic White people, Hispanic ethnicity, with an HR of 1.22 (95% CI 1.18-1.25, p < 0.0001), remained a significant independent contributor to mortality risk. CONCLUSIONS: Hispanics had the greatest female-to-male IRR ratio, a greater prevalence of advanced disease features at diagnosis, along with the highest AAMR and increased mortality risk despite adjustments for demographic and tumor covariates. Further investigation into other risk factors is needed.

When to Transfer: Predictors of Pediatric High Flow Nasal Cannula Failure at a Community Hospital.

OBJECTIVES: To identify risk factors of high flow nasal cannula (HFNC) failure at a US pediatric hospital without a co-located ICU. METHODS: Retrospective cohort study of patients aged 0 to 18 years who were started on HFNC in the emergency department or inpatient unit at a community hospital over a 16-month period. Children with chronic medical conditions were excluded. Outcome was HFNC failure, defined as HFNC need greater than floor limit, noninvasive positive pressure, or mechanical ventilation. In bivariate analysis, we compared demographic and clinical factors between those with and without failure. We included variables in a multivariable model on the basis of statistical significance. We used Poisson regression with robust error variance to calculate the adjusted relative risk (aRR) of failure for each variable. RESULTS: Of 195 children, 51% had HFNC failure. In adjusted analysis, failure was higher in all age groups <12 months as compared with older children. For example, children aged 3 to 5 months had a higher risk of failure compared with patients 12 months or older (aRR 1.85, confidence interval [CI] 1.34-2.54). Patients with an asthma exacerbation had a higher risk of failure (aRR 1.39, CI 1.03-1.88). Patients whose respiratory rate or heart rate did not improve also had a higher risk of failure (aRR 1.73, CI 1.24-2.41; aRR 1.47, CI 1.14-1.90). CONCLUSIONS: Patients who were younger, had asthma, and did not have improved respiratory rate or heart rate after HFNC were more likely to experience HFNC failure.

Total Margin Control Is Superior to Traditional Margin Assessment for Treatment of Low-Stage Penile Squamous Cell Carcinoma.

PURPOSE: Penile cancer is rare, with significant morbidity and limited literature assessing utility of peripheral and deep en face margin assessment (PDEMA) vs traditional margin assessment (vertical sections) on treatment outcomes. MATERIALS AND METHODS: This was a 32-year retrospective multicenter cohort study at 3 academic tertiary care centers. The cohort consisted of 189 patients with histologic diagnosis of in situ or T1a cutaneous squamous cell carcinoma of the penis at Brigham and Women's, Massachusetts General Hospital (1988-2020), and Memorial Sloan Kettering Cancer Center (1995-2020) treated with PDEMA surgical excision, excision/circumcision, or penectomy/glansectomy. Local recurrence, metastasis, and disease-specific death were assessed via multivariable Cox proportional hazard models. RESULTS: The cohort consisted of 189 patients. Median age at diagnosis was 62 years. Median tumor diameter was 1.3 cm. The following outcomes of interest occurred: 30 local recurrences, 13 metastases, and 5 disease-specific deaths. Primary tumors were excised with PDEMA (N = 30), excision/circumcision (N = 110), or penectomy/glansectomy (N = 49). Of patients treated with traditional margin assessment (non-PDEMA), 12% had narrow or positive margins. Five-year proportions were as follows with respect to local recurrence-free survival, metastasis-free survival, and disease-specific survival/progression-free survival, respectively: 100%, 100%, and 100% following PDEMA; 82%, 96%, and 99% following excision/circumcision; 83%, 91%, and 95% following penectomy/glansectomy. A limitation is that this multi-institutional cohort study was not externally validated. CONCLUSIONS: Initial results are encouraging that PDEMA surgical management effectively controls early-stage penile squamous cell carcinoma.

Depressive symptoms prospectively increase risk for new onset cigarette and ENDS dependence symptoms.

Little research has examined the new onset of cigarette and Electronic Nicotine Delivery System (ENDS) dependence symptoms among young adults. This study aims to 1) examine new onset cigarette and ENDS dependence symptoms over a 4.5-year period and 2) examine how depressive symptoms impact new onset dependence symptoms among young adults. Participants were drawn from 24 colleges in Texas who were participating in a multi-wave cohort study (2014-2019). The present study included 4536 participants aged 18-25 who did not report cigarette or ENDS dependence symptoms at wave 1 (64.1% female; 65.2% non-white; m age = 20.62 [SD = 1.80] at wave 1). Cox's regression models were employed to determine the hazard of new onset cigarette and ENDS dependence symptoms overall and the impact of depressive symptoms. Models controlled for sociodemographic factors and other tobacco product use. 14.4% of participants reported new onset cigarette dependence symptoms and 14.6% reported new onset ENDS dependence symptoms over the 4.5 years of the study. Depressive symptoms significantly predicted increased risk for new onset cigarette (HR = 1.30, CI = [1.21, 1.39]) and ENDS (HR = 1.20, CI = [1.12, 1.29]) dependence symptoms. Young adults exhibited dependence symptoms for cigarettes and ENDS products at similar rates across the 4.5 years of the study. Elevated depressive symptoms increased risk of new onset cigarette and ENDS dependence symptoms, advancing evidence for the self-medication hypothesis. Tobacco and nicotine prevention and cessation programs and messaging are needed particularly among young adults who experience depressive symptoms.

Monitoring and reporting the US COVID-19 vaccination effort.

Immunizations are an important tool to reduce the burden of vaccine preventable diseases and improve population health.1 High-quality immunization data is essential to inform clinical and public health interventions and respond to outbreaks of vaccine-preventable diseases. To track COVID-19 vaccines and vaccinations, CDC established an integrated network that included vaccination provider systems, health information exchange systems, immunization information systems, pharmacy and dialysis systems, vaccine ordering systems, electronic health records, and tools to support mass vaccination clinics. All these systems reported data to CDC's COVID-19 response system (either directly or indirectly) where it was processed, analyzed, and disseminated. This unprecedented vaccine tracking effort provided essential information for public health officials that was used to monitor the COVID-19 response and guide decisions. This paper will describe systems, processes, and policies that enabled monitoring and reporting of COVID-19 vaccination efforts and share challenges and lessons learned for future public health emergency responses.

Factors Associated With Actionable Gastrointestinal Panel Results in Hospitalized Children.

OBJECTIVES: There is uncertainty regarding which hospitalized patients with acute gastroenteritis (AGE) benefit from gastrointestinal panel (GIP) testing. Unnecessary testing may lead to increased costs, overdiagnosis, and overtreatment. In general, AGE management and outcomes are most impacted if an actionable (bacterial or parasitic) result is obtained. We aimed to assess which clinical reasons for ordering GIP testing ("order indications") and patient factors were associated with actionable results. METHODS: This is a cross-sectional study of pediatric patients hospitalized between 2015 and 2018 at a large pediatric health care system with diarrhea and a GIP performed. Multivariable regression analysis was used to determine associations between actionable GIP results and order indication, stool frequency, and demographics. Findings were evaluated in patients with complex chronic conditions (CCC) and non-CCC patients. RESULTS: There were 1124 GIPs performed in 967 encounters. Non-CCC patients had more actionable results than CCC patients, and reasons for testing differed. Across both cohorts, age ≥1 year old was positively associated with actionable results. For non-CCC patients, actionable results were associated with "diarrhea with blood or pus" order indication and nonwinter season; international travel was associated with non-Clostridioides difficile bacteria and parasites. No order indications were associated with actionable results for CCC patients. CONCLUSIONS: Patient factors and order indications that may help identify children hospitalized for AGE with actionable GIP results include older age (regardless of CCC status), as well as bloody stools and international travel in previously healthy children. Prospective validation of these findings could help improve diagnostic stewardship and decrease unnecessary testing.

Complete response with pembrolizumab in recurrent squamous cell carcinoma of the oral tongue: A case report.

Immunotherapies such as immune checkpoint inhibitors have shown promising results in solid tumors associated with BRCA2, but there are no consistent predictors for who will respond to immunotherapy. More research is needed on the impact of this mutation in head and neck squamous cell carcinomas, particularly for recurrent/metastatic tumors. We report a case of stage IV oral squamous cell carcinoma associated with BRCA2 mutation that achieved complete remission with pembrolizumab treatment for relapsed disease.

School-Level Socioeconomic Status and Nutrient Content of Outdoor Food/Beverage Advertisements.

We examined if areas around schools with more students of lower socioeconomic status (SES) have more total food/beverage advertisements and/or more advertisements with poorer nutritional content as compared to areas around schools with fewer students with lower SES. All outdoor food/beverage advertisements within a half-mile radius of 47 middle and high schools in the United States were objectively documented in 2012 and coded for nutritional content. The total number of advertisements and the macronutrient and micronutrient contents (total calories, fat (g), protein (g), carbohydrate (g), sugar (g), and sodium (mg)) of food and beverage items depicted in the advertisements were calculated. In total, 9132 unique advertisements were recorded, with 3153 ads displaying food and beverages that could be coded for nutrient content. Schools located in areas of lower SES (≥60% students receiving free/reduced-price lunch) had significantly more advertisements displaying food and beverages that could be coded for nutrient content (z = 2.01, p = 0.04), as well as advertisements that contained more sodium (z = 2.20, p = 0.03), as compared to schools located in areas of higher SES. There were no differences in calorie, fat, protein, carbohydrate, or sugar content. Policies to reduce the prevalence of outdoor food and beverage advertising are warranted.

Objective Clinical Measurement Tools for Functional Evaluation of the Surgical Patient.

Following knee surgery, clinicians have traditionally used visually rated or time-based assessments of lower extremity movement quality to measure surgical outcomes, plan rehabilitation interventions, and measure success. These methods of assessment are prone to error and do not fully capture a patient's inefficient movement patterns post surgery. Further, currently available systems which objectively measure kinematics during these tasks are expensive and unidimensional. For these reasons, recent research has called for the development of objective and low-cost precision rehabilitation tools to improve clinical measurement of movement tasks. The purpose of this article is to highlight two such tools and their applications to knee surgery. The systems highlighted within this article are the Mizzou Point-of-Care Assessment System (MPASS) and the Mizzou Knee Arthrometer Testing System (MKATS). MPASS has demonstrated high levels of agreement with the gold-standard Vicon system in measuring kinematics during sit-to-stand (R > 0.71), lateral step-down (intraclass correlation coefficient [ICC] > 0.55, apart from ankle flexion), and drop vertical jump tasks (ICC > 0.62), as well as gait (R > 0.87). MKATS has been used to quantify differences in tibiofemoral motion between groups during lateral step-down, step-up-and-over, and step-up/step-down tasks. Objective measurement of clinical tasks using portable and inexpensive instruments, such as the MPASS and MKATS, can help clinicians identify inefficient movement patterns and asymmetries which may damage and wear down supporting structures within the knee and throughout the kinetic chain causing pain and discomfort. Identifying these issues can help clinicians to plan interventions and measure their progress at a lower cost than currently available systems. The MPASS and MKATS are useful tools which have many applications to knee surgery.

Experiences in the delivery of preconception and pregnancy care for LGBTIQA+ people: A systematic review and thematic synthesis of patient and healthcare provider perspectives.

BACKGROUND: The widespread availability of reproductive technology and family planning services has led to an increase in the number of available pathways to parenthood for LGBTIQA+ people. However, emerging research indicates that significant healthcare inequities have been documented among LGBTIQA+ people and attributed to the pervasiveness of structural and systemic discrimination that extends to preconception and pregnancy care. AIM: The aim of this systematic review was to synthesise qualitative research that has explored the experiences of LGBTIQA+ people in navigating preconception and pregnancy care services to inform healthcare quality improvement. METHOD: Six databases were searched for relevant research published between 2012 and 2023. The findings of all included studies underwent a secondary thematic synthesis, and methodological quality was assessed using the Joanna Briggs Institute Checklist for Qualitative Research. FINDINGS: A total of 37 studies were eligible for inclusion. Four major themes were constructed through thematic synthesis: (1) unavailability of information, services, and support; (2) clinical competencies of healthcare staff; (3) hetero- and cis-sexist care experiences; and (4) discrimination and traumatisation. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: The findings of this review indicate that LGBTIQA+ people experience significant challenges during the journey towards parenthood, marked predominantly by the pervasiveness of inequity, and defined by discriminatory healthcare processes. This review has led to several recommendations for future healthcare quality improvement through an investment in policies, procedures, and interactions that are sensitive to the needs of LGBTIQA+ people. Importantly, future research must be co-designed and led by LGBTIQA+ community input.

Moderators and Mediators of the Relationship of Shared Decision-Making and Satisfaction.

Background:Evidence suggests that health literacy, perceived availability of information and guidance to adapt to challenges (informational support), and symptoms of depression all have the potential to mediate or moderate the relationship between patient-rated involvement in decisions and satisfaction with care. If so these could be useful targets for improving patient experience. Methods: We prospectively enrolled 130 new adult patients visiting an orthopedic surgeon over a 4-month period. All patients were asked to complete measures of satisfaction with care (21-item Medical Interview Satisfaction Scale), perceived involvement in decisions (9-item Shared Decision-Making Questionnaire), symptoms of depression (the Patient-Reported Outcomes Measurement Information Scale [PROMIS] Depression Computerized Adaptive Test [CAT]), perceived availability of information and guidance to adapt to challenges (PROMIS Informational Support CAT), and the Newest Vital Sign test of health literacy. Results: The strong correlation between satisfaction with care (ρ = 0.60, P < .001) and perceived involvement in decisions was neither mediated nor moderated by health literacy, perceived availability of information and guidance, and symptoms of depression. Conclusions: The observation that patient-rated shared decision-making is strongly related to satisfaction with an office visit, independent of health literacy, perceived support, and symptoms of depression, is consistent with evidence that various measures of patient experience tend to correlate and emphasizes the importance of the patient-clinician relationship. Level of Evidence: Level II, prospective study.

Exposure to tobacco retail outlet tobacco marketing and initiation of cigarette and e-cigarette use: Depressive symptoms as a moderator.

INTRODUCTION: While tobacco retail outlet (TRO) marketing exposure has been associated with tobacco use, little research has explored how this relationship may vary by the experience of depressive symptoms. The purpose of this study was to examine if the relationship between TRO tobacco marketing exposure and tobacco use initiation is moderated by depressive symptoms among young adults. METHODS: Participants were drawn from 24 colleges in Texas who were participating in a multi-wave cohort study (2014-2019). The present study included 2020 cigarette or ENDS naïve participants at wave 2 (69.2% female; 32.1% white; m age=20.6 [SD=2.0] at wave 1). Generalized mixed-effects logistic regression analyses were used to examine the association between cigarette and ENDS TRO marketing exposure and subsequent initiation for both products with depressive symptoms as a moderator. RESULTS: The interaction between cigarette marketing and depressive symptoms was significant (OR=1.38 95% CI=[1.04,1.83]). Cigarette marketing did not impact cigarette initiation among participants with low depressive symptoms (OR=0.96 95% CI= [0.64,1.45]), but did impact cigarette initiation among participants with high depressive symptoms (OR=1.83 95% CI=[1.23,2.74]). There was no interaction effect for ENDS initiation. Main effects showed that ENDS marketing exposure predicted ENDS initiation (OR=1.43 95% CI=[1.10,1.87]). CONCLUSIONS: Exposure to tobacco marketing at TROs is an important risk factor for initiation of cigarette and ENDS use, particularly for cigarette initiation among those who experience greater levels of depressive symptoms. Future work is needed to better understand why this type of marketing is influential for this group.

Serial Subtraction Alters Lateral Step-down Tibiofemoral Kinematics in Healthy Adults.

This study evaluated the effects of two types of cognitive dual-tasking on three-dimensional knee kinematics during the lateral step-down. 19 healthy individuals (22.05±1.61 yrs., 173.92±9.21 cm, 67.99±12.65 kg) participated in this study. Participants completed 5 repetitions of a lateral step-down task for each leg and each testing condition (control, Stroop, and serial subtraction by seven). An electromagnetic motion sensor was attached to the femur via compression clamp placed about the medial and lateral epicondyles. Another sensor was attached 2 cm below the ipsilateral tibial tuberosity. A custom MATLAB algorithm located the knee joint axis of rotation from dynamic knee flexion and extension. Discrete kinematics at peak flexion were used in this study. Paired samples t-tests were used to compare average frontal, transverse, and sagittal plane knee position at maximum flexion between conditions for each leg. No significant differences were found for either limb between control and Stroop conditions. Comparisons revealed significant differences in frontal and transverse plane knee angles at peak flexion between the control and serial subtraction by seven conditions. These findings indicate serial subtraction by seven requires different cognitive processing abilities which may cause greater interference with some aspects of motor control.

The effect of clear aligners on speech: a systematic review.

OBJECTIVE: To assess the effect of clear aligners on the speech of patients undergoing orthodontic therapy through a systematic review of the literature. Search methods and selection criteria: The protocol of this systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) CRD42021278694. An electronic search of the Scopus, Embase, Pubmed, and Web of Science databases was done for papers published between January 2000 till September 2021. Studies that evaluated speech difficulties in patients undergoing orthodontic treatment with clear aligners using objective and subjective analyses were included. The evaluated primary outcome was speech difficulties. Secondary outcomes were time to adaptation and recovery from speech difficulties. Study quality was assessed based on the Cochrane Handbook for Systematic Reviews of Interventions Handbook guidelines and ROBINS-I tool. RESULTS: Two hundred and eighty-three articles were screened to identify seven studies (n = 332 patients) that assessed speech difficulty with aligners, of which two were randomized trials. Meta-analysis was not performed due to the heterogeneity in the study designs. Five studies compared speech difficulty with aligners to fixed appliances. Two studies showed a moderate risk of bias and five studies had a serious risk of bias. Level of evidence was downgraded to low due to the methodological insufficiencies and risk of bias in the studies. All seven studies reported that aligners could influence the clarity and delivery of speech, similar to fixed appliances. Various phonemes were affected including /s/,/z/,/zh/,/sh/,/th/,/ch/ on wearing aligners. Errors in articulation of consonants and sibilants were noted with lisping and speech impairment. These speech difficulties were temporary and most patients recovered in 7-14 days while few patients took 30-60 days to recover. CONCLUSION: The likelihood of speech difficulties appears high with clear aligners. However, patients adapt quickly and speech returns to normal. The results of this review must be interpreted with caution and more well-designed randomized trials examining long-term effects of aligners on speech are indicated. CLINICAL SIGNIFICANCE: Orthodontists should counsel patients opting for clear aligner treatment of the potential transient speech difficulties. REGISTRATION: The protocol for this systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) CRD42021278694.