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41.
Aim: To describe how reliability assessment data in the WHO Multicentre Growth Reference Study (MGRS) were collected and analysed, and to present the results thereof.
Methods: There were two sources of anthropometric data (length, head and arm circumferences, triceps and subscapular skinfolds, and height) for these analyses. Data for constructing the WHO Child Growth Standards, collected in duplicate by observer pairs, were used to calculate inter-observer technical error of measurement (TEM) and the coefficient of reliability. The second source was the anthropometry standardization sessions conducted throughout the data collection period with the aim of identifying and correcting measurement problems. An anthropometry expert visited each site annually to participate in standardization sessions and provide remedial training as required. Inter- and intra-observer TEM, and average bias relative to the expert, were calculated for the standardization data.
Results: TEM estimates for teams compared well with the anthropometry expert. Overall, average bias was within acceptable limits of deviation from the expert, with head circumference having both lowest bias and lowest TEM. Teams tended to underestimate length, height and arm circumference, and to overestimate skinfold measurements. This was likely due to difficulties associated with keeping children fully stretched out and still for length/height measurements and in manipulating soft tissues for the other measurements. Intra- and inter-observer TEMs were comparable, and newborns, infants and older children were measured with equal reliability. The coefficient of reliability was above 95% for all measurements except skinfolds whose R coefficient was 75–93%.
Conclusion: Reliability of the MGRS teams compared well with the study's anthropometry expert and published reliability statistics.  相似文献   
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WHO Child Growth Standards based on length/height, weight and age   总被引:18,自引:0,他引:18  
Aim: To describe the methods used to construct the WHO Child Growth Standards based on length/height, weight and age, and to present resulting growth charts. Methods: The WHO Child Growth Standards were derived from an international sample of healthy breastfed infants and young children raised in environments that do not constrain growth. Rigorous methods of data collection and standardized procedures across study sites yielded very high-quality data. The generation of the standards followed methodical, state-of-the-art statistical methodologies. The Box-Cox power exponential (BCPE) method, with curve smoothing by cubic splines, was used to construct the curves. The BCPE accommodates various kinds of distributions, from normal to skewed or kurtotic, as necessary. A set of diagnostic tools was used to detect possible biases in estimated percentiles or z-score curves. Results: There was wide variability in the degrees of freedom required for the cubic splines to achieve the best model. Except for length/height-for-age, which followed a normal distribution, all other standards needed to model skewness but not kurtosis. Length-for-age and height-for-age standards were constructed by fitting a unique model that reflected the 0.7-cm average difference between these two measurements. The concordance between smoothed percentile curves and empirical percentiles was excellent and free of bias. Percentiles and z-score curves for boys and girls aged 0–60 mo were generated for weight-for-age, length/height-for-age, weight-for-length/height (45 to 110 cm and 65 to 120 cm, respectively) and body mass index-for-age.
Conclusion: The WHO Child Growth Standards depict normal growth under optimal environmental conditions and can be used to assess children everywhere, regardless of ethnicity, socio-economic status and type of feeding.  相似文献   
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IntroductionThe global prevalence of diabetes in 2019 in adults was estimated to be 9.3%. This study developed in Ecuador, for the first time, instruments to assess patient‐reported outcomes and experiences.MethodsThe Experiences of the Person with Diabetes (EPD) Questionnaire is a diabetes‐specific instrument. A mixed‐methods study was conducted. First, a qualitative item development phase that included four focus groups and six semi‐structured interviews with patients was conducted in different rural and urban areas of Ecuador to obtain information on culture, beliefs, demographics, diet and social perspectives. A second quantitative phase for psychometric validation was carried out in primary care settings of rural and urban areas of Ecuador.ResultsForty‐two and four hundred and eighty‐nine participants were included in each phase, respectively. The item development phase resulted in a questionnaire of 44 items (23 for perceived outcomes and 21 for experiences). In the validation study, most participants were women (58%) and from urban areas (57%). Exploratory factor analysis revealed three dimensions for each instrument. Outcomes instrument dimensions were symptoms and burnout, worries and fears and social limitations. Experiences instrument dimensions were information, patient‐centred care and care delivery. Cronbach''s α values of the total score and dimensions were high, ranging between .81 and .93 in both instruments. Confirmatory factor analysis showed an acceptable fit of the data.ConclusionThe EPD Questionnaire is probably the first instrument developed to assess patient‐reported experiences and perceived outcomes in a middle‐income country that included patients to capture all dimensions relevant for the intended population. Its psychometric properties are robust and could provide valuable information for clinicians and policymakers in the region.Patient or Public ContributionThe development of these instruments has taken into consideration patients and the public since their conception. A qualitative approach gathered relevant information related to the cultural, social and economic burden of different populations in Ecuador. Before validation, a pilot test was carried out with users of the National Health Services to obtain their perspectives and insights of the developed instrument. Finally, during the data analysis, we have given special consideration to social variables such as rural and urban populations.  相似文献   
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Background: Vitamin D plays a role in bone health, pain signaling, and inflammation. We examined the largely unknown relation of dietary vitamin D intake with pain incidence and pain changes over time in older adults. Methods: Data were taken from the Seniors-ENRICA-1 cohort, which included 950 individuals aged ≥60 years. Habitual vitamin D intake was assessed in 2012 with a validated diet history, and pain both in 2012 and 2017 with a scale ranging from 0 (no pain) to 6 (highest pain), according to its severity, frequency, and number of locations. Analyses on pain incidence and pain changes were performed in the 524 participants free of pain at baseline and the overall sample, respectively. Results: Higher dietary vitamin D intake was associated with lower 5-year pain incidence; the multivariable-adjusted odds ratio (95% confidence interval) was 0.88 (0.79,0.99) for every 1-µg/day increase in vitamin D intake, and 0.49 (0.28,0.88) for the highest (>3.52 µg/day) vs. lowest (<1.85 µg/day) tertile. Dietary vitamin D intake (highest vs. lowest tertile) was also associated with 5-year favorable pain changes: the multivariable-adjusted odds ratio of pain worsening vs. no change/pain improvement was 0.55 (0.36,0.86), and the β coefficient for changes in the pain scale was −0.56 (−1.03,−0.09). Similar results were found for pain severity, frequency, and number of pain locations. Conclusions: In an older adult population, where compliance with vitamin D intake recommendations was very low, a slightly increased dietary intake was associated with lower pain incidence and favorable pain changes over 5 years.  相似文献   
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Background:Pneumonia is a frequent diagnosis for patients admitted to Australian intensive care units (ICUs) for invasive ventilation. Physiotherapists in ICU provide interventions to enhance respiratory function and physical recovery.Objective:This retrospective cohort study aimed to describe physiotherapy management of adults with pneumonia who require invasive mechanical ventilation in a single Level 3 ICU in a quaternary teaching hospital.Methods:All adults admitted with a medical diagnosis of pneumonia requiring invasive mechanical ventilation over a two-year period were included. Demographic and clinical data, including APACHE II score, ventilator-free days (VFDs) to day 28, ICU length of stay (LOS), and type and frequency of physiotherapy episodes of care delivered in ICU, were collected from electronic medical records. Correlations between VFDs to day 28 and the frequency of physiotherapy interventions delivered per subject were examined using Spearman’s rho analysis.Results:From 208 records screened, 66 subjects with an ICU admission diagnosis of pneumonia, who required invasive mechanical ventilation, were included. Median (IQR) ICU LOS was 10 (5–17) days, and mortality rate was 15.2% (n=10). The cohort had a median of 20.5 (IQR 2–25) VFDs to day 28. Community-acquired pneumonia (66.7%, n=44) was the most frequent type of pneumonia diagnosis. There were 1110 episodes of physiotherapy care, with patients receiving a median of 13.5 (IQR 6.8–21.3) episodes during their ICU stay, with a median rate of 1.2 (IQR 1.0–1.6) episodes per day. Over 96.7% of patients with pneumonia received physiotherapy treatment during their ICU stay. Overall, physiotherapy treatments consisting only of respiratory techniques were most commonly provided (55.1%, n=612). Airway suctioning (92.4%, n=61), patient positioning (72.7%, n=48) or positioning advice to nurses (77.3%, n=51), and hyperinflation techniques (63.6%, n=42) were among the respiratory techniques most delivered.Conclusion:This study described the current intensive care physiotherapy management in a single center for adults with pneumonia who required invasive mechanical ventilation, demonstrating that respiratory physiotherapy interventions are often provided for this ICU patient cohort. Further research is warranted to determine the efficacy of respiratory physiotherapy interventions to justify their use for ICU patients with pneumonia receiving invasive mechanical ventilation.  相似文献   
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Staphylococcus epidermidis has emerged as the most important pathogen in infections related to indwelling medical devices, and although these infections are not life-threatening, their frequency and the fact that they are extremely difficult to treat represent a serious burden on the public health system. Treatment is complicated by specific antibiotic resistance genes and the formation of biofilms. Hence, novel therapeutic strategies are needed to fight these infections. A novel bacteriophage CUB-EPI_14 specific to the bacterial species S. epidermidis was isolated from sewage and characterized genomically and phenotypically. Its genome contains a total of 46,098 bp and 63 predicted genes, among which some have been associated with packaging and lysis-associated proteins, structural proteins, or DNA- and metabolism-associated proteins. No lysogeny-associated proteins or known virulence proteins were identified in the phage genome. CUB-EPI_14 showed stability over a wide range of temperatures (from −20 °C to 50 °C) and pH values (pH 3–pH 12) and a narrow host range against S. epidermidis. Potent antimicrobial and antibiofilm activities were observed when the phage was tested against a highly susceptible bacterial isolate. These encouraging results open the door to new therapeutic opportunities in the fight against resilient biofilm-associated infections caused by S. epidermidis.  相似文献   
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Non-alcoholic fatty liver disease (NAFLD) is currently considered the most common cause of liver disease. Its prevalence is increasing in parallel with the obesity and type 2 diabetes mellitus (DM2) epidemics in developed countries. Several recent studies have suggested that NAFLD may be the hepatic manifestation of a systemic inflammatory metabolic disease that also affects other organs, such as intestine, lungs, skin and vascular endothelium. It appears that local and systemic proinflammatory/anti-inflammatory cytokine imbalance, together with insulin resistance and changes in the intestinal microbiota, are pathogenic mechanisms shared by NAFLD and other comorbidities. NAFLD is more common in patients with extrahepatic diseases such as inflammatory bowel disease (IBD), obstructive syndrome apnea (OSA) and psoriasis than in the general population. Furthermore, there is evidence that this association has a negative impact on the severity of liver lesions. Specific risk characteristics for NAFLD have been identified in populations with IBD (i.e. age, obesity, DM2, previous bowel surgery, IBD evolution time, methotrexate treatment), OSA (i.e. obesity, DM2, OSA severity, increased transaminases) and psoriasis (i.e. age, metabolic factors, severe psoriasis, arthropathy, elevated transaminases, methotrexate treatment). These specific phenotypes might be used by gastroenterologists, pneumologists and dermatologists to create screening algorithms for NAFLD. Such algorithms should include non-invasive markers of fibrosis used in NAFLD to select subjects for referral to the hepatologist. Prospective, controlled studies in NAFLD patients with extrahepatic comorbidities are required to demonstrate a causal relationship and also that appropriate multidisciplinary management improves these patients’ prognosis and survival.  相似文献   
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