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Diabetologia Jan 2022International trends in traditional diabetes complications (cardiovascular, renal, peripheral vascular, ophthalmic, hepatic or neurological diseases) and mortality rates... (Review)
Review
International trends in traditional diabetes complications (cardiovascular, renal, peripheral vascular, ophthalmic, hepatic or neurological diseases) and mortality rates are poorly characterised. An earlier review of studies published up to 2015 demonstrated that most data come from a dozen high-income countries (HICs) in North America, Europe or the Asia-Pacific region and that, in these countries at least, rates of acute glycaemic fluctuations needing medical attention and amputations, myocardial infarction and mortality were all declining over the period. Here, we provide an updated review of published literature on trends in type 2 diabetes complications and mortality in adults since 2015. We also discuss issues related to data collection, analysis and reporting that have influenced global trends in type 2 diabetes and its complications. We found that most data on trends in type 2 diabetes, its complications and mortality come from a small number of HICs with comprehensive surveillance systems, though at least some low- and middle-income countries (LMICs) from Africa and Latin America are represented in this review. The published data suggest that HICs have experienced declines in cardiovascular complication rates and all-cause mortality in people with diabetes. In parallel, cardiovascular complications and mortality rates in people with diabetes have increased over time in LMICs. However, caution is warranted in interpreting trends from LMICs due to extremely sparse data or data that are not comparable across countries. We noted that approaches to case ascertainment and definitions of complications and mortality (numerators) and type 2 diabetes (the denominator) vary widely and influence the interpretation of international data. We offer four key recommendations to more rigorously document trends in rates of type 2 diabetes complications and mortality, over time and worldwide: (1) increasing investments in data collection systems; (2) standardising case definitions and approaches to ascertainment; (3) strengthening analytical capacity; and (4) developing and implementing structured guidelines for reporting of data.
Topics: Adult; Africa; Blood Glucose; Diabetes Complications; Diabetes Mellitus, Type 2; Global Health; Humans; Mortality
PubMed: 34837505
DOI: 10.1007/s00125-021-05585-2 -
Pulmonary Circulation 2021This systematic review of literature and online reports critically appraised incidence and prevalence estimates of pulmonary arterial hypertension and chronic...
Epidemiology of pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension: identification of the most accurate estimates from a systematic literature review.
This systematic review of literature and online reports critically appraised incidence and prevalence estimates of pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension to identify the most accurate estimates. Medline® and Embase® databases were searched for articles published between 1 January 2003 and 31 August 2020. Studies were grouped according to whether they were registries (population-based estimates), clinical databases (hospital-based estimates) or claims/administrative databases. Registries were classified into systematic and non-systematic registries, according to whether every national centre participated. Of 7309 publications identified, 5414 were screened after removal of duplicates and 33 were included. Inclusion was based on study type, availability of a clear numerator (diagnosed population) and a population- or hospital-based denominator, or all primary data required to calculate estimates. Only the most recent publication from a database was included. Most studies were based on European data and very few included children. In adults, the range of estimates per million was approximately 20-fold for pulmonary arterial hypertension incidence (1.5-32) and prevalence (12.4-268) and of similar magnitude for chronic thromboembolic pulmonary hypertension incidence (0.9-39) and prevalence (14.5-144). Recent (≤5 years) national systematic registry data from centralised healthcare systems provided the following ranges in adult estimates per million: approximately 5.8 for pulmonary arterial hypertension incidence, 47.6-54.7 for pulmonary arterial hypertension prevalence, 3.1-6.0 for chronic thromboembolic pulmonary hypertension incidence and 25.8-38.4 for chronic thromboembolic pulmonary hypertension prevalence. These estimates were considered the most reliable and consistent for the scientific community to plan for resource allocation and improve detection rates.
PubMed: 33456755
DOI: 10.1177/2045894020977300 -
Journal of Clinical Epidemiology Oct 2020
Topics: COVID-19; Data Analysis; Evaluation Studies as Topic; Evidence-Based Medicine; Female; Humans; Male; Mathematics; Policy Making; SARS-CoV-2
PubMed: 32980129
DOI: 10.1016/j.jclinepi.2020.09.013 -
PloS One 2016To correct the incongruence of document types between the numerator and denominator in the traditional impact factor (IF), we make a corresponding adjustment to its... (Comparative Study)
Comparative Study
To correct the incongruence of document types between the numerator and denominator in the traditional impact factor (IF), we make a corresponding adjustment to its formula and present five corrective IFs: IFTotal/Total, IFTotal/AREL, IFAR/AR, IFAREL/AR, and IFAREL/AREL. Based on a survey of researchers in the fields of ophthalmology and mathematics, we obtained the real impact ranking of sample journals in the minds of peer experts. The correlations between various IFs and questionnaire score were analyzed to verify their journal evaluation effects. The results show that it is scientific and reasonable to use five corrective IFs for journal evaluation for both ophthalmology and mathematics. For ophthalmology, the journal evaluation effects of the five corrective IFs are superior than those of traditional IF: the corrective effect of IFAR/AR is the best, IFAREL/AR is better than IFTotal/Total, followed by IFTotal/AREL, and IFAREL/AREL. For mathematics, the journal evaluation effect of traditional IF is superior than those of the five corrective IFs: the corrective effect of IFTotal/Total is best, IFAREL/AR is better than IFTotal/AREL and IFAREL/AREL, and the corrective effect of IFAR/AR is the worst. In conclusion, not all disciplinary journal IF need correction. The results in the current paper show that to correct the IF of ophthalmologic journals may be valuable, but it seems to be meaningless for mathematic journals.
Topics: Algorithms; Journal Impact Factor; Mathematics; Ophthalmology; Periodicals as Topic; Surveys and Questionnaires; United States
PubMed: 26977697
DOI: 10.1371/journal.pone.0151414 -
Human Reproduction (Oxford, England) Dec 2016Which outcome measures are reported in RCTs for IVF? (Review)
Review
STUDY QUESTION
Which outcome measures are reported in RCTs for IVF?
SUMMARY ANSWER
Many combinations of numerator and denominator are in use, and are often employed in a manner that compromises the validity of the study.
WHAT IS KNOWN ALREADY
The choice of numerator and denominator governs the meaning, relevance and statistical integrity of a study's results. RCTs only provide reliable evidence when outcomes are assessed in the cohort of randomised participants, rather than in the subgroup of patients who completed treatment.
STUDY DESIGN, SIZE, DURATION
Review of outcome measures reported in 142 IVF RCTs published in 2013 or 2014.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Trials were identified by searching the Cochrane Gynaecology and Fertility Specialised Register. English-language publications of RCTs reporting clinical or preclinical outcomes in peer-reviewed journals in the period 1 January 2013 to 31 December 2014 were eligible. Reported numerators and denominators were extracted. Where they were reported, we checked to see if live birth rates were calculated correctly using the entire randomised cohort or a later denominator.
MAIN RESULTS AND THE ROLE OF CHANCE
Over 800 combinations of numerator and denominator were identified (613 in no more than one study). No single outcome measure appeared in the majority of trials. Only 22 (43%) studies reporting live birth presented a calculation including all randomised participants or only excluding protocol violators. A variety of definitions were used for key clinical numerators: for example, a consensus regarding what should constitute an ongoing pregnancy does not appear to exist at present.
LIMITATIONS, REASONS FOR CAUTION
Several of the included articles may have been secondary publications. Our categorisation scheme was essentially arbitrary, so the frequencies we present should be interpreted with this in mind. The analysis of live birth denominators was post hoc.
WIDER IMPLICATIONS OF THE FINDINGS
There is massive diversity in numerator and denominator selection in IVF trials due to its multistage nature, and this causes methodological frailty in the evidence base. The twin spectres of outcome reporting bias and analysis of non-randomised comparisons do not appear to be widely recognised. Initiatives to standardise outcome reporting, such as requiring all effectiveness studies to report live birth or cumulative live birth, are welcome. However, there is a need to recognise that early outcomes of treatment, such as stimulation response or embryo quality, may be appropriate choices of primary outcome for early phase studies.
STUDY FUNDING/COMPETING INTERESTS
J.W. is funded by a Doctoral Research Fellowship from the National Institute for Health Research. The views expressed in this publication are those of the authors and not necessarily those of the NHS, the National Institute for Health Research or the Department of Health. J.W. also declares that publishing research is beneficial to his career. J.W. and A.V. are statistical editors, and M.S. is Information Specialist, for the Cochrane Gynaecology and Fertility Group, although the views expressed here are not necessarily those of the group. D.R.B. is funded by the NHS as Scientific Director of a clinical IVF service. The authors declare no other conflicts of interest.
Topics: Birth Rate; Female; Fertilization in Vitro; Humans; Live Birth; Outcome Assessment, Health Care; Ovulation Induction; Pregnancy; Pregnancy Rate; Research Design; Treatment Outcome
PubMed: 27664214
DOI: 10.1093/humrep/dew227 -
BMC Pregnancy and Childbirth Mar 2021Annually, 14 million newborns require stimulation to initiate breathing at birth and 6 million require bag-mask-ventilation (BMV). Many countries have invested in... (Observational Study)
Observational Study
BACKGROUND
Annually, 14 million newborns require stimulation to initiate breathing at birth and 6 million require bag-mask-ventilation (BMV). Many countries have invested in facility-based neonatal resuscitation equipment and training. However, there is no consistent tracking for neonatal resuscitation coverage.
METHODS
The EN-BIRTH study, in five hospitals in Bangladesh, Nepal, and Tanzania (2017-2018), collected time-stamped data for care around birth, including neonatal resuscitation. Researchers surveyed women and extracted data from routine labour ward registers. To assess accuracy, we compared gold standard observed coverage to survey-reported and register-recorded coverage, using absolute difference, validity ratios, and individual-level validation metrics (sensitivity, specificity, percent agreement). We analysed two resuscitation numerators (stimulation, BMV) and three denominators (live births and fresh stillbirths, non-crying, non-breathing). We also examined timeliness of BMV. Qualitative data were collected from health workers and data collectors regarding barriers and enablers to routine recording of resuscitation.
RESULTS
Among 22,752 observed births, 5330 (23.4%) babies did not cry and 3860 (17.0%) did not breathe in the first minute after birth. 16.2% (n = 3688) of babies were stimulated and 4.4% (n = 998) received BMV. Survey-report underestimated coverage of stimulation and BMV. Four of five labour ward registers captured resuscitation numerators. Stimulation had variable accuracy (sensitivity 7.5-40.8%, specificity 66.8-99.5%), BMV accuracy was higher (sensitivity 12.4-48.4%, specificity > 93%), with small absolute differences between observed and recorded BMV. Accuracy did not vary by denominator option. < 1% of BMV was initiated within 1 min of birth. Enablers to register recording included training and data use while barriers included register design, documentation burden, and time pressure.
CONCLUSIONS
Population-based surveys are unlikely to be useful for measuring resuscitation coverage given low validity of exit-survey report. Routine labour ward registers have potential to accurately capture BMV as the numerator. Measuring the true denominator for clinical need is complex; newborns may require BMV if breathing ineffectively or experiencing apnoea after initial drying/stimulation or subsequently at any time. Further denominator research is required to evaluate non-crying as a potential alternative in the context of respectful care. Measuring quality gaps, notably timely provision of resuscitation, is crucial for programme improvement and impact, but unlikely to be feasible in routine systems, requiring audits and special studies.
Topics: Adolescent; Adult; Bangladesh; Data Accuracy; Female; Humans; Infant, Newborn; Live Birth; Male; Masks; Nepal; Perinatal Death; Positive-Pressure Respiration; Pregnancy; Registries; Resuscitation; Stillbirth; Surveys and Questionnaires; Tanzania; Young Adult
PubMed: 33765958
DOI: 10.1186/s12884-020-03422-9 -
International Journal of Sports... Feb 2021In the article Bartram JC, Thewlis D, Martin DT, Norton KI. Accuracy of W′ recovery kinetics in high performance cyclists—modeling intermittent work capacity. Int J...
In the article Bartram JC, Thewlis D, Martin DT, Norton KI. Accuracy of W′ recovery kinetics in high performance cyclists—modeling intermittent work capacity. Int J Sports Physiol Perform. 2018;13(6):724–728, https://doi.org/10.1123/ijspp.2017-0034, there was a typo in the equation for Skiba 2 in Figure 1—the numerator and denominator of the ending fraction in the last centered equation were transposed. The online version of this article has been corrected. The authors apologize for the error.
PubMed: 36626652
DOI: 10.1123/ijspp.2020-0912 -
Acta Psychologica Feb 2021Fractions are crucial, from math and science education to daily activities, but they are hard. A puzzling aspect of fractions is that people over-rely on the numerator...
Fractions are crucial, from math and science education to daily activities, but they are hard. A puzzling aspect of fractions is that people over-rely on the numerator when comparing a pair of fractions. Previous work has considered this numerator bias mostly as a reasoning mishap. Still, in a vast amount of pairwise comparisons, across many real-world domains, not just education textbooks, we report a high prior probability that the larger fraction has the larger numerator, and, for a relevant case, we provide formal arguments why. The existence of such a regularity suggests that the numerator bias may reflect a rational adaptation that detects and exploits likely events. In a pair of visual-proportion tasks (discrete and continuous fractions), we confirm that the numerator bias in participants adapts to experimented regularities. Even though weak education and math abilities play a role, adaptation to informative priors outside the classroom poses a challenge to educators, learners, and decision-makers.
Topics: Bias; Cognition; Humans; Mathematics; Problem Solving
PubMed: 33453615
DOI: 10.1016/j.actpsy.2020.103248 -
Spatial and Spatio-temporal Epidemiology Nov 2020Problems related to unknown or imprecisely measured populations at risk are common in epidemiologic studies of disease frequency. The size of the population at risk is... (Review)
Review
Problems related to unknown or imprecisely measured populations at risk are common in epidemiologic studies of disease frequency. The size of the population at risk is typically conceptualized as a denominator to be used in combination with a count of disease cases (a numerator) to calculate incidence or prevalence. However, the size of the population at risk can take other epidemiologic properties in relation to an exposure of interest and the count outcome, including confounding, modification, and mediation. Using spatial ecological studies of injury incidence as an example, we identify and evaluate five approaches that researchers have used to address "unknown denominator problems": ignoring, controlling for a proxy, approximating, controlling by study design, and measuring the population at risk. We present a case example and recommendations for selecting a solution given the data and the hypothesized relationship between an exposure of interest, a count outcome, and the population at risk.
Topics: Accidents, Traffic; Confounding Factors, Epidemiologic; Humans; Incidence; New York City; Population Surveillance; Research Design; Spatio-Temporal Analysis; Wounds and Injuries
PubMed: 33138954
DOI: 10.1016/j.sste.2020.100361