Association of osteoarthritis risk factors with knee and hip pain in a population-based sample of 29-59 year olds in Denmark: a cross-sectional analysis.

BACKGROUND: This study aimed to a) describe the prevalence of knee and hip osteoarthritis risk factors in a population of 29-59 year old individuals, b) estimate the association between persistent knee/hip pain and osteoarthritis risk factors, and c) describe the prevalence of osteoarthritis risk factors, including specific biomechanical risk factors, in individuals with prolonged persistent knee or hip pain. METHODS: Participants completed the "Early Detection and Prevention" pilot study questionnaire, including items on presence of knee/hip pain within the last month and osteoarthritis risk factors. Individuals reporting knee/hip problems completed a second questionnaire, including items about most problematic joint and specific biomechanical osteoarthritis risk factors. After describing the prevalence of persistent knee/hip pain and osteoarthritis risk factors among respondents stratified for sex and age, logistic regression was used to estimate the strength of associations between osteoarthritis risk factors and presence of knee/hip pain. The prevalence of prolonged persistent pain (i.e. knee/hip pain reported at both questionnaires) and osteoarthritis risk factors among respondents with prolonged persistent knee and hip pain, were described. RESULTS: Two thousand six hundred sixty-one respondents completed the first survey. The one-month prevalence of persistent knee/hip pain was 27%. Previous knee/hip injury was associated with persistent knee/hip pain for both sexes in all age groups, while a family history of osteoarthritis was associated with persistent knee/hip pain in all age groups except for 29-39 year old men. A higher BMI was associated with persistent knee/hip pain in 40-59 year old women, and 50-59 year old men. Eight hundred sixty seven respondents completed the second questionnaire. Knee/hip injuries and surgeries were more common in individuals with prolonged persistent knee than hip pain. CONCLUSIONS: Knee/hip pain within the last month was frequent among individuals aged 29-59 years. Multiple known osteoarthritis risk factors were associated with presence of knee/hip pain. Joint injury and previous surgery were more common in individuals with knee than hip pain. The results support the notion that joint injury and overweight during early adulthood are signs of a trajectory towards symptomatic osteoarthritis later in life and may help earlier identification of groups at high risk of future symptomatic osteoarthritis. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT02797392 ). Registered April 29,2016

Statistical Multiplicity in Systematic Reviews of Anaesthesia Interventions: A Quantification and Comparison between Cochrane and Non-Cochrane Reviews

BACKGROUND: Systematic reviews with meta-analyses often contain many statistical tests. This multiplicity may increase the risk of type I error. Few attempts have been made to address the problem of statistical multiplicity in systematic reviews. Before the implications are properly considered, the size of the issue deserves clarification. Because of the emphasis on bias evaluation and because of the editorial processes involved, Cochrane reviews may contain more multiplicity than their non-Cochrane counterparts. This study measured the quantity of statistical multiplicity present in a population of systematic reviews and aimed to assess whether this quantity is different in Cochrane and non-Cochrane reviews. METHODS/PRINCIPAL FINDINGS: We selected all the systematic reviews published by the Cochrane Anaesthesia Review Group containing a meta-analysis and matched them with comparable non-Cochrane reviews. We counted the number of statistical tests done in each systematic review. The median number of tests overall was 10 (interquartile range (IQR) 6 to 18). The median was 12 in Cochrane and 8 in non-Cochrane reviews (difference in medians 4 (95% confidence interval (CI) 2.0-19.0). The proportion that used an assessment of risk of bias as a reason for doing extra analyses was 42% in Cochrane and 28% in non-Cochrane reviews (difference in proportions 14% (95% CI -8 to 36). The issue of multiplicity was addressed in 6% of all the reviews. CONCLUSION/SIGNIFICANCE: Statistical multiplicity in systematic reviews requires attention. We found more multiplicity in Cochrane reviews than in non-Cochrane reviews. Many of the reasons for the increase in multiplicity may well represent improved methodological approaches and greater transparency, but multiplicity may also cause an increased risk of spurious conclusions. Few systematic reviews, whether Cochrane or non-Cochrane, address the issue of multiplicity

The assessment of neuromuscular fatigue during 120 min of simulated soccer exercise

Purpose This investigation examined the development of neuromuscular fatigue during a simulated soccer match incorporating a period of extra time (ET) and the reliability of these responses on repeated test occasions. Methods Ten male amateur football players completed a 120 min soccer match simulation (SMS). Before, at half time (HT), full time (FT), and following a period of ET, twitch responses to supramaximal femoral nerve and transcranial magnetic stimulation (TMS) were obtained from the knee-extensors to measure neuromuscular fatigue. Within 7 days of the first SMS, a second 120 min SMS was performed by eight of the original ten participants to assess the reliability of the fatigue response. Results At HT, FT, and ET, reductions in maximal voluntary force (MVC; −11, −20 and −27%, respectively, P ≤ 0.01), potentiated twitch force (−15, −23 and −23%, respectively, P < 0.05), voluntary activation (FT, −15 and ET, −18%, P ≤ 0.01), and voluntary activation measured with TMS (−11, −15 and −17%, respectively, P ≤ 0.01) were evident. The fatigue response was robust across both trials; the change in MVC at each time point demonstrated a good level of reliability (CV range 6–11%; ICC2,1 0.83–0.94), whilst the responses identified with motor nerve stimulation showed a moderate level of reliability (CV range 5–18%; ICC2,1 0.63–0.89) and the data obtained with motor cortex stimulation showed an excellent level of reliability (CV range 3–6%; ICC2,1 0.90–0.98). Conclusion Simulated soccer exercise induces a significant level of fatigue, which is consistent on repeat tests, and involves both central and peripheral mechanisms

Playing exposure does not affect movement characteristics or physiological responses of elite youth footballers during an intensified period of competition.

This is an Accepted Manuscript of an article published by Taylor & Francis in Science and Medicine in Football on 08/05/18, available online: https://www.tandfonline.com/doi/full/10.1080/24733938.2018.1470664This study investigated the effect of playing time on physiological and perceptual responses to six, 60 min matches played over five days. Thirty youth football players (age = 14.1 ± 0.4 years; body mass = 57.4 ± 12.9 kg; stature 169.3 ± 7.7 cm) were grouped into low (<250 min; LPG, n = 18) and high (≥250 min; HPG, n = 12) match exposure groups and monitored daily for lower body power and perceived wellness. GPS technology was used to assess match running demands in total distance (m•min-1), low (<13 km•h-1) and high (≥13 km•h-1) speed running categories. Hypothesis based testing and effect sizes (ES) were used to analyse data. The HPG performed moderately more total distance (103.7 ± 10.4 cf. 90.2 ± 19.7 m•min-1, P = 0.03; ES=0.74 ± 0.63) and high speed running (26.7 ± 6.6 cf. 20.3 ± 6.5 m•min-1, P = 0.01; ES=0.87 ± 0.6) than the LPG across all six matches. Differences of a small magnitude were observed between groups for lower body power (P = 0.08; ES =0.59 ± 0.8) and perceived wellness (P = 0.09; ES=0.42 ± 0.4) which were both higher in the HPG. Youth football players appear well equipped to deal with intensified period of competition, such as those experienced in tournaments, irrespective of match exposure

Protocol for a sequential, prospective meta-analysis to describe coronavirus disease 2019 (COVID-19) in the pregnancy and postpartum periods.

We urgently need answers to basic epidemiological questions regarding SARS-CoV-2 infection in pregnant and postpartum women and its effect on their newborns. While many national registries, health facilities, and research groups are collecting relevant data, we need a collaborative and methodologically rigorous approach to better combine these data and address knowledge gaps, especially those related to rare outcomes. We propose that using a sequential, prospective meta-analysis (PMA) is the best approach to generate data for policy- and practice-oriented guidelines. As the pandemic evolves, additional studies identified retrospectively by the steering committee or through living systematic reviews will be invited to participate in this PMA. Investigators can contribute to the PMA by either submitting individual patient data or running standardized code to generate aggregate data estimates. For the primary analysis, we will pool data using two-stage meta-analysis methods. The meta-analyses will be updated as additional data accrue in each contributing study and as additional studies meet study-specific time or data accrual thresholds for sharing. At the time of publication, investigators of 25 studies, including more than 76,000 pregnancies, in 41 countries had agreed to share data for this analysis. Among the included studies, 12 have a contemporaneous comparison group of pregnancies without COVID-19, and four studies include a comparison group of non-pregnant women of reproductive age with COVID-19. Protocols and updates will be maintained publicly. Results will be shared with key stakeholders, including the World Health Organization (WHO) Maternal, Newborn, Child, and Adolescent Health (MNCAH) Research Working Group. Data contributors will share results with local stakeholders. Scientific publications will be published in open-access journals on an ongoing basis