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Working with partial hand prostheses: An investigation into experiences of clinicians.
Carlyle K ,Buis A ,Donovan-Hall M ,Day S ... - 《-》
被引量: - 发表:1970年 -
The methacholine challenge test (MCT) is a standard evaluation method of assessing airway hyperresponsiveness (AHR) and its severity, and has significant clinical value in the diagnosis and treatment of bronchial asthma. A consensus working group consisting of experts from the Pulmonary Function and Clinical Respiratory Physiology Committee of the Chinese Association of Chest Physicians, the Task Force for Pulmonary Function of the Chinese Thoracic Society, and the Pulmonary Function Group of Respiratory Branch of the Chinese Geriatric Society jointly developed this consensus. Based on the "" published in 2014, the issues encountered in its use, and recent developments, the group has updated the Through an extensive collection of expert opinions, literature reviews, questionnaire surveys, and multiple rounds of online and offline discussions, the consensus addressed the eleven core issues in MCT's clinical practice, including indications, contraindications, preparation of provocative agents, test procedures and methods, quality control, safety management, interpretation of results, and reporting standards. The aim was to provide clinical pulmonary function practitioners in healthcare institutions with the tools to optimize the use of this technique to guide clinical diagnosis and treatment. Who is suitable for conducting MCT? What are contraindications for performing MCT?Patients with atypical symptoms and a clinical suspicion of asthma, patients diagnosed with asthma requiring assessment of the severity of airway hyperresponsiveness, individuals with allergic rhinitis who are at risk of developing asthma, patients in need of evaluating the effectiveness of asthma treatment, individuals in occupations with high safety risks due to airway hyperresponsiveness, patients with chronic diseases prone to airway hyperresponsiveness, others requiring assessment of airway reactivity.Absolute contraindications: (1) Patients who are allergic to methacholine (MCh) or other parasympathomimetic drugs, with allergic reactions including rash, itching/swelling (especially of the face, tongue, and throat), severe dizziness, and dyspnea; (2) Patients with a history of life-threatening asthma attacks or those who have required mechanical ventilation for asthma attacks in the past three months; (3) Patients with moderate to severe impairment of baseline pulmonary function [Forced Expiratory Volume in one second (FEV) less than 60% of the predicted value or FEV<1.0 L]; (4) Severe urticaria; (5) Other situations inappropriate for forced vital capacity (FVC) measurement, such as myocardial infarction or stroke in the past three months, poorly controlled hypertension, aortic aneurysm, recent eye surgery, or increased intracranial pressure.Relative contraindications: (1) Moderate or more severe impairment of baseline lung function (FEV%pred<70%), but individuals with FEV%pred>60% may still be considered for MCT with strict observation and adequate preparation; (2) Experiencing asthma acute exacerbation; (3) Poor cooperation with baseline lung function tests that do not meet quality control requirements; (4) Recent respiratory tract infection (<4 weeks); (5) Pregnant or lactating women; (6) Patients currently using cholinesterase inhibitors (for the treatment of myasthenia gravis); (7) Patients who have previously experienced airway spasm during pulmonary function tests, with a significant decrease in FEV even without the inhalation of provocative. How to prepare and store the challenge solution for MCT?Before use, the drug must be reconstituted and then diluted into various concentrations for provocation. The dilution concentration and steps for MCh vary depending on the inhalation method and provocation protocol used. It is important to follow specific steps. Typically, a specified amount of diluent is added to the methacholine reagent bottle for reconstitution, and the mixture is shaken until the solution becomes clear. The diluent is usually physiological saline, but saline with phenol (0.4%) can also be used. Phenol can reduce the possibility of bacterial contamination, and its presence does not interfere with the provocation test. After reconstitution, other concentrations of MCh solution are prepared using the same diluent, following the dilution steps, and then stored separately in sterile containers. Preparers should carefully verify and label the concentration and preparation time of the solution and complete a preparation record form. The reconstituted and diluted MCh solution is ready for immediate use without the need for freezing. It can be stored for two weeks if refrigerated (2-8 ℃). The reconstituted solution should not be stored directly in the nebulizer reservoir to prevent crystallization from blocking the capillary opening and affecting aerosol output. The temperature of the solution can affect the production of the nebulizer and cause airway spasms in the subject upon inhaling cold droplets. Thus, refrigerated solutions should be brought to room temperature before use. What preparation is required for subjects prior to MCT?(1) Detailed medical history inquiry and exclusion of contraindications.(2) Inquiring about factors and medications that may affect airway reactivity and assessing compliance with medication washout requirements: When the goal is to evaluate the effectiveness of asthma treatment, bronchodilators other than those used for asthma treatment do not need to be discontinued. Antihistamines and cromolyn have no effect on MCT responses, and the effects of a single dose of inhaled corticosteroids and leukotriene modifiers are minimal, thus not requiring cessation before the test. For patients routinely using corticosteroids, whether to discontinue the medication depends on the objective of the test: if assisting in the diagnosis of asthma, differential diagnosis, aiding in step-down therapy for asthma, or exploring the effect of discontinuing anti-inflammatory treatment, corticosteroids should be stopped before the provocation test; if the patient is already diagnosed with asthma and the objective is to observe the level of airway reactivity under controlled medication conditions, then discontinuation is not necessary. Medications such as IgE monoclonal antibodies, IL-4Rα monoclonal antibodies, traditional Chinese medicine, and ethnic medicines may interfere with test results, and clinicians should decide whether to discontinue these based on the specific circumstances.(3) Explaining the test procedure and potential adverse reactions, and obtaining informed consent if necessary. What are the methods of the MCT? And which ones are recommended in current clinical practice?Commonly used methods for MCT in clinical practice include the quantitative nebulization method (APS method), Forced Oscillalion method (Astograph method), 2-minute tidal breathing method (Cockcroft method), hand-held quantitative nebulization method (Yan method), and 5-breath method (Chai 5-breath method). The APS method allows for precise dosing of inhaled Methacholine, ensuring accurate and reliable results. The Astograph method, which uses respiratory resistance as an assessment indicator, is easy for subjects to perform and is the simplest operation. These two methods are currently the most commonly used clinical practice in China. What are the steps involved in MCT?The MCT consists of the following four steps:(1) Baseline lung function test: After a 15-minute rest period, the subjects assumes a seated position and wear a nose clip for the measurement of pulmonary function indicators [such as FEV or respiratory resistance (Rrs)]. FEV should be measured at least three times according to spirometer quality control standards, ensuring that the best two measurements differ by less than 150 ml and recording the highest value as the baseline. Usually, if FEV%pred is below 70%, proceeding with the challenge test is not suitable, and a bronchodilation test should be considered. However, if clinical assessment of airway reactivity is necessary and FEV%pred is between 60% and 70%, the provocation test may still be conducted under close observation, ensuring the subject's safety. If FEV%pred is below 60%, it is an absolute contraindication for MCT.(2) Inhalation of diluent and repeat lung function test for control values: the diluent, serving as a control for the inhaled MCh, usually does not significantly impact the subject's lung function. the higher one between baseline value and the post-dilution FEV is used as the reference for calculating the rate of FEV decline. If post-inhalation FEV decreases, there are usually three scenarios: ①If FEV decreases by less than 10% compared to the baseline, the test can proceed, continue the test and administer the first dose of MCh. ②If the FEV decreases by≥10% and<20%, indicating a heightened airway reactivity to the diluent, proceed with the lowest concentration (dose) of the provoking if FEV%pred has not yet reached the contraindication criteria for the MCT. if FEV%pred<60% and the risk of continuing the challenge test is considerable, it is advisable to switch to a bronchodilation test and indicate the change in the test results report. ③If FEV decreases by≥20%, it can be directly classified as a positive challenge test, and the test should be discontinued, with bronchodilators administered to alleviate airway obstruction.(3) Inhalation of MCh and repeat lung function test to assess decline: prepare a series of MCh concentrations, starting from the lowest and gradually increasing the inhaled concentration (dose) using different methods. Perform pulmonary function tests at 30 seconds and 90 seconds after completing nebulization, with the number of measurements limited to 3-4 times. A complete Forced Vital Capacity (FVC) measurement is unnecessary during testing; only an acceptable FEV measurement is required. The interval between two consecutive concentrations (doses) generally should not exceed 3 minutes. If FEV declines by≥10% compared to the control value, reduce the increment of methacholine concentration (dose) and adjust the inhalation protocol accordingly. If FEV declines by≥20% or more compared to the control value or if the maximum concentration (amount) has been inhaled, the test should be stopped. After inhaling the MCh, close observation of the subject's response is necessary. If necessary, monitor blood oxygen saturation and auscultate lung breath sounds. The test should be promptly discontinued in case of noticeable clinical symptoms or signs.(4) Inhalation of bronchodilator and repeat lung function test to assess recovery: when the bronchial challenge test shows a positive response (FEV decline≥20%) or suspiciously positive, the subject should receive inhaled rapid-acting bronchodilators, such as short-acting beta-agonists (SABA) or short-acting muscarinic antagonists (SAMA). Suppose the subject exhibits obvious symptoms of breathlessness, wheezing, or typical asthma manifestations, and wheezing is audible in the lungs, even if the positive criteria are not met. In that case, the challenge test should be immediately stopped, and rapid-acting bronchodilators should be administered. Taking salbutamol as an example, inhale 200-400 μg (100 μg per puff, 2-4 puffs, as determined by the physician based on the subject's condition). Reassess pulmonary function after 5-10 minutes. If FEV recovers to within 10% of the baseline value, the test can be concluded. However, if there is no noticeable improvement (FEV decline still≥10%), record the symptoms and signs and repeat the bronchodilation procedure as mentioned earlier. Alternatively, add Ipratropium bromide (SAMA) or further administer nebulized bronchodilators and corticosteroids for intensified treatment while keeping the subject under observation until FEV recovers to within 90% of the baseline value before allowing the subject to leave. What are the quality control requirements for the APS and Astograph MCT equipment?(1) APS Method Equipment Quality Control: The APS method for MCT uses a nebulizing inhalation device that requires standardized flowmeters, compressed air power source pressure and flow, and nebulizer aerosol output. Specific quality control methods are as follows:a. Flow and volume calibration of the quantitative nebulization device: Connect the flowmeter, an empty nebulization chamber, and a nebulization filter in sequence, attaching the compressed air source to the bottom of the chamber to ensure airtight connections. Then, attach a 3 L calibration syringe to the subject's breathing interface and simulate the flow during nebulization (typically low flow:<2 L/s) to calibrate the flow and volume. If calibration results exceed the acceptable range of the device's technical standards, investigate and address potential issues such as air leaks or increased resistance due to a damp filter, then recalibrate. Cleaning the flowmeter or replacing the filter can change the resistance in the breathing circuit, requiring re-calibration of the flow.b. Testing the compressed air power source: Regularly test the device, connecting the components as mentioned above. Then, block the opening of the nebulization device with a stopper or hand, start the compressed air power source, and test its pressure and flow. If the test results do not meet the technical standards, professional maintenance of the equipment may be required.c. Verification of aerosol output of the nebulization chamber: Regularly verify all nebulization chambers used in provocation tests. Steps include adding a certain amount of saline to the chamber, weighing and recording the chamber's weight (including saline), connecting the nebulizer to the quantitative nebulization device, setting the nebulization time, starting nebulization, then weighing and recording the post-nebulization weight. Calculate the unit time aerosol output using the formula [(weight before nebulization-weight after nebulization)/nebulization time]. Finally, set the nebulization plan for the provocation test based on the aerosol output, considering the MCh concentration, single inhalation nebulization duration, number of nebulization, and cumulative dose to ensure precise dosing of the inhaled MCh.(2) Astograph method equipment quality control: Astograph method equipment for MCT consists of a respiratory resistance monitoring device and a nebulization medication device. Perform zero-point calibration, volume calibration, impedance verification, and nebulization chamber checks daily before tests to ensure the resistance measurement system and nebulization system function properly. Calibration is needed every time the equipment is turned on, and more frequently if there are significant changes in environmental conditions.a. Zero-point calibration: Perform zero-point calibration before testing each subject. Ensure the nebulization chamber is properly installed and plugged with no air leaks.b. Volume calibration: Use a 3 L calibration syringe to calibrate the flow sensor at a low flow rate (approximately 1 L/s).c. Resistance verification: Connect low impedance tubes (1.9-2.2 cmHO·L·s) and high impedance tubes (10.2-10.7 cmHO·L·s) to the device interface for verification.d. Bypass check: Start the bypass check and record the bypass value; a value>150 ml/s is normal.e. Nebulization chamber check: Check each of the 12 nebulization chambers daily, especially those containing bronchodilators, to ensure normal spraying. The software can control each nebulization chamber to produce spray automatically for a preset duration (e.g., 2 seconds). Observe the formation of water droplets on the chamber walls, indicating normal spraying. If no nebulization occurs, check for incorrect connections or blockages. How to set up and select the APS method in MCT?The software program of the aerosol provocation system in the quantitative nebulization method can independently set the nebulizer output, concentration of the methacholine agent, administration time, and number of administrations and combine these parameters to create the challenge test process. In principle, the concentration of the methacholine agent should increase from low to high, and the dose should increase from small to large. According to the standard, a 2-fold or 4-fold incremental challenge process is generally used. In clinical practice, the dose can be simplified for subjects with good baseline lung function and no history of wheezing, such as using a recommended 2-concentration, 5-step method (25 and 50 g/L) and (6.25 and 25 g/L). Suppose FEV decreases by more than 10% compared to the baseline during the test to ensure subject safety. In that case, the incremental dose of the methacholine agent can be reduced, and the inhalation program can be adjusted appropriately. If the subject's baseline lung function declines or has recent daytime or nighttime symptoms such as wheezing or chest tightness, a low concentration, low dose incremental process should be selected. What are the precautions for the operation process of the Astograph method in MCT?(1) Test equipment: The Astograph method utilizes the forced oscillation technique, applying a sinusoidal oscillating pressure at the mouthpiece during calm breathing. Subjects inhale nebulized MCh of increasing concentrations while continuous monitoring of respiratory resistance (Rrs) plots the changes, assessing airway reactivity and sensitivity. The nebulization system employs jet nebulization technology, comprising a compressed air pump and 12 nebulization cups. The first cup contains saline, cups 2 to 11 contain increasing concentrations of MCh, and the 12th cup contains a bronchodilator solution.(2) Provocation process: Prepare 10 solutions of MCh provocant with gradually increasing concentrations.(3) Operational procedure: The oscillation frequency is usually set to 3 Hz (7 Hz for children) during the test. The subject breathes calmly, inhales saline solution nebulized first, and records the baseline resistance value (if the subject's baseline resistance value is higher than 10 cmHO·L·s, the challenge test should not be performed). Then, the subject gradually inhales increasing concentrations of methacholine solution. Each concentration solution is inhaled for 1 minute, and the nebulization system automatically switches to the next concentration for inhalation according to the set time. Each nebulizer cup contains 2-3 ml of solution, the output is 0.15 ml/min, and each concentration is inhaled for 1 minute. The dose-response curve is recorded automatically. Subjects should breathe tidally during the test, avoiding deep breaths and swallowing. Continue until Rrs significantly rises to more than double the baseline value, or if the subject experiences notable respiratory symptoms or other discomfort, such as wheezing in both lungs upon auscultation. At this point, the inhalation of the provocant should be stopped and the subject switchs to inhaling a bronchodilator until Rrs returns to pre-provocation levels. If there is no significant increase in Rrs, stop the test after inhaling the highest concentration of MCh. How to interpret the results of the MCT?The method chosen for the MCT determines the specific indicators used for interpretation. The most commonly used indicator is FEV, although other parameters such as Peak Expiratory Flow (PEF) and Rrs can also be used to assess airway hyperresponsiveness. The test results can be classified as positive, suspiciously positive, or negative, based on a combination of the judgment indicators and changes in the subject's symptoms. If FEV decreases by≥20% compared to the baseline value after not completely inhaling at the highest concentration, the result can be judged as positive for Methacholine bronchial challenge test. If the patient has obvious wheezing symptoms or wheezing is heard in both lungs, but the challenge test does not meet the positive criteria (the highest dose/concentration has been inhaled), and FEV decreases between 10% and 20% compared to the baseline level, the result can also be judged as positive. If FEV decreases between 15% and 20% compared to the baseline value without dyspnea or wheezing attacks, the result can be judged as suspiciously positive. Astograph method: If Rrs rises to 2 times or more of the baseline resistance before reaching the highest inhalation concentration, or if the subject's lungs have wheezing and severe coughing, the challenge test can be judged as positive. Regardless of the result of the Methacholine bronchial challenge test, factors that affect airway reactivity, such as drugs, seasons, climate, diurnal variations, and respiratory tract infections, should be excluded. When using the APS method, the severity of airway hyperresponsiveness can be graded based on PD-FEV or PC-FEV. Existing evidence suggests that PD shows good consistency when different nebulizers, inhalation times, and starting concentrations of MCh are used for bronchial provocation tests, whereas there is more variability with PC. Therefore, PD is often recommended as the quantitative assessment indicator. The threshold value for PD with the APS method is 2.5 mg.The Astograph method often uses the minimum cumulative dose (Dmin value, in Units) to reflect airway sensitivity. Dmin is the minimum cumulative dose of MCh required to produce a linear increase in Rrs. A dose of 1 g/L of the drug concentration inhaled for 1-minute equals 1 unit. It's important to note that with the continuous increase in inhaled provocant concentration, the concept of cumulative dose in the Astograph method should not be directly compared to other methods. Most asthma patients have a Dmin<10 Units, according to Japanese guidelines. The Astograph method, having been used in China for over twenty years, suggests a high likelihood of asthma when Dmin≤6 Units, with a smaller Dmin value indicating a higher probability. When Dmin is between 6 and 10 Units, further differential diagnosis is advised to ascertain whether the condition is asthma.A negative methacholine challenge test (MCT) does not entirely rule out asthma. The test may yield negative results due to the following reasons:(1) Prior use of medications that reduce airway responsiveness, such as β2 agonists, anticholinergic drugs, antihistamines, leukotriene receptor antagonists, theophylline, corticosteroids, etc., and insufficient washout time.(2) Failure to meet quality control standards in terms of pressure, flow rate, particle size, and nebulization volume of the aerosol delivery device.(3) Poor subject cooperation leads to inadequate inhalation of the methacholine agent.(4) Some exercise-induced asthma patients may not be sensitive to direct bronchial challenge tests like the Methacholine challenge and require indirect bronchial challenge tests such as hyperventilation, cold air, or exercise challenge to induce a positive response.(5) A few cases of occupational asthma may only react to specific antigens or sensitizing agents, requiring specific allergen exposure to elicit a positive response.A positive MCT does not necessarily indicate asthma. Other conditions can also present with airway hyperresponsiveness and yield positive results in the challenge test, such as allergic rhinitis, chronic bronchitis, viral upper respiratory infections, allergic alveolitis, tropical eosinophilia, cystic fibrosis, sarcoidosis, bronchiectasis, acute respiratory distress syndrome, post-cardiopulmonary transplant, congestive heart failure, and more. Furthermore, factors like smoking, air pollution, or exercise before the test may also result in a positive bronchial challenge test. What are the standardized requirements for the MCT report?The report should include: (1) basic information about the subject; (2) examination data and graphics: present baseline data, measurement data after the last two challenge doses or concentrations in tabular form, and the percentage of actual measured values compared to the baseline; flow-volume curve and volume-time curve before and after challenge test; dose-response curve: showing the threshold for positive challenge; (3) opinions and conclusions of the report: including the operator's opinions, quality rating of the examination, and review opinions of the reviewing physician. What are the adverse reactions and safety measures of MCT?During the MCT, the subject needs to repeatedly breathe forcefully and inhale bronchial challenge agents, which may induce or exacerbate bronchospasm and contraction and may even cause life-threatening situations. Medical staff should be fully aware of the indications, contraindications, medication use procedures, and emergency response plans for the MCT.
Pulmonary Function and Clinical Respiratory Physiology Committee of Chinese Association of Chest Physicians ,Chinese Thoracic Society ,Pulmonary Function Group of Respiratory Branch of Chinese Geriatric Society 《-》
被引量: - 发表:2024年 -
Description of the condition Malaria, an infectious disease transmitted by the bite of female mosquitoes from several Anopheles species, occurs in 87 countries with ongoing transmission (WHO 2020). The World Health Organization (WHO) estimated that, in 2019, approximately 229 million cases of malaria occurred worldwide, with 94% occurring in the WHO's African region (WHO 2020). Of these malaria cases, an estimated 409,000 deaths occurred globally, with 67% occurring in children under five years of age (WHO 2020). Malaria also negatively impacts the health of women during pregnancy, childbirth, and the postnatal period (WHO 2020). Sulfadoxine/pyrimethamine (SP), an antifolate antimalarial, has been widely used across sub-Saharan Africa as the first-line treatment for uncomplicated malaria since it was first introduced in Malawi in 1993 (Filler 2006). Due to increasing resistance to SP, in 2000 the WHO recommended that one of several artemisinin-based combination therapies (ACTs) be used instead of SP for the treatment of uncomplicated malaria caused by Plasmodium falciparum (Global Partnership to Roll Back Malaria 2001). However, despite these recommendations, SP continues to be advised for intermittent preventive treatment in pregnancy (IPTp) and intermittent preventive treatment in infants (IPTi), whether the person has malaria or not (WHO 2013). Description of the intervention Folate (vitamin B9) includes both naturally occurring folates and folic acid, the fully oxidized monoglutamic form of the vitamin, used in dietary supplements and fortified food. Folate deficiency (e.g. red blood cell (RBC) folate concentrations of less than 305 nanomoles per litre (nmol/L); serum or plasma concentrations of less than 7 nmol/L) is common in many parts of the world and often presents as megaloblastic anaemia, resulting from inadequate intake, increased requirements, reduced absorption, or abnormal metabolism of folate (Bailey 2015; WHO 2015a). Pregnant women have greater folate requirements; inadequate folate intake (evidenced by RBC folate concentrations of less than 400 nanograms per millilitre (ng/mL), or 906 nmol/L) prior to and during the first month of pregnancy increases the risk of neural tube defects, preterm delivery, low birthweight, and fetal growth restriction (Bourassa 2019). The WHO recommends that all women who are trying to conceive consume 400 micrograms (µg) of folic acid daily from the time they begin trying to conceive through to 12 weeks of gestation (WHO 2017). In 2015, the WHO added the dosage of 0.4 mg of folic acid to the essential drug list (WHO 2015c). Alongside daily oral iron (30 mg to 60 mg elemental iron), folic acid supplementation is recommended for pregnant women to prevent neural tube defects, maternal anaemia, puerperal sepsis, low birthweight, and preterm birth in settings where anaemia in pregnant women is a severe public health problem (i.e. where at least 40% of pregnant women have a blood haemoglobin (Hb) concentration of less than 110 g/L). How the intervention might work Potential interactions between folate status and malaria infection The malaria parasite requires folate for survival and growth; this has led to the hypothesis that folate status may influence malaria risk and severity. In rhesus monkeys, folate deficiency has been found to be protective against Plasmodium cynomolgi malaria infection, compared to folate-replete animals (Metz 2007). Alternatively, malaria may induce or exacerbate folate deficiency due to increased folate utilization from haemolysis and fever. Further, folate status measured via RBC folate is not an appropriate biomarker of folate status in malaria-infected individuals since RBC folate values in these individuals are indicative of both the person's stores and the parasite's folate synthesis. A study in Nigeria found that children with malaria infection had significantly higher RBC folate concentrations compared to children without malaria infection, but plasma folate levels were similar (Bradley-Moore 1985). Why it is important to do this review The malaria parasite needs folate for survival and growth in humans. For individuals, adequate folate levels are critical for health and well-being, and for the prevention of anaemia and neural tube defects. Many countries rely on folic acid supplementation to ensure adequate folate status in at-risk populations. Different formulations for folic acid supplements are available in many international settings, with dosages ranging from 400 µg to 5 mg. Evaluating folic acid dosage levels used in supplementation efforts may increase public health understanding of its potential impacts on malaria risk and severity and on treatment failures. Examining folic acid interactions with antifolate antimalarial medications and with malaria disease progression may help countries in malaria-endemic areas determine what are the most appropriate lower dose folic acid formulations for at-risk populations. The WHO has highlighted the limited evidence available and has indicated the need for further research on biomarkers of folate status, particularly interactions between RBC folate concentrations and tuberculosis, human immunodeficiency virus (HIV), and antifolate antimalarial drugs (WHO 2015b). An earlier Cochrane Review assessed the effects and safety of iron supplementation, with or without folic acid, in children living in hyperendemic or holoendemic malaria areas; it demonstrated that iron supplementation did not increase the risk of malaria, as indicated by fever and the presence of parasites in the blood (Neuberger 2016). Further, this review stated that folic acid may interfere with the efficacy of SP; however, the efficacy and safety of folic acid supplementation on these outcomes has not been established. This review will provide evidence on the effectiveness of daily folic acid supplementation in healthy and malaria-infected individuals living in malaria-endemic areas. Additionally, it will contribute to achieving both the WHO Global Technical Strategy for Malaria 2016-2030 (WHO 2015d), and United Nations Sustainable Development Goal 3 (to ensure healthy lives and to promote well-being for all of all ages) (United Nations 2021), and evaluating whether the potential effects of folic acid supplementation, at different doses (e.g. 0.4 mg, 1 mg, 5 mg daily), interferes with the effect of drugs used for prevention or treatment of malaria. To examine the effects of folic acid supplementation, at various doses, on malaria susceptibility (risk of infection) and severity among people living in areas with various degrees of malaria endemicity. We will examine the interaction between folic acid supplements and antifolate antimalarial drugs. Specifically, we will aim to answer the following. Among uninfected people living in malaria endemic areas, who are taking or not taking antifolate antimalarials for malaria prophylaxis, does taking a folic acid-containing supplement increase susceptibility to or severity of malaria infection? Among people with malaria infection who are being treated with antifolate antimalarials, does folic acid supplementation increase the risk of treatment failure? Criteria for considering studies for this review Types of studies Inclusion criteria Randomized controlled trials (RCTs) Quasi-RCTs with randomization at the individual or cluster level conducted in malaria-endemic areas (areas with ongoing, local malaria transmission, including areas approaching elimination, as listed in the World Malaria Report 2020) (WHO 2020) Exclusion criteria Ecological studies Observational studies In vivo/in vitro studies Economic studies Systematic literature reviews and meta-analyses (relevant systematic literature reviews and meta-analyses will be excluded but flagged for grey literature screening) Types of participants Inclusion criteria Individuals of any age or gender, living in a malaria endemic area, who are taking antifolate antimalarial medications (including but not limited to sulfadoxine/pyrimethamine (SP), pyrimethamine-dapsone, pyrimethamine, chloroquine and proguanil, cotrimoxazole) for the prevention or treatment of malaria (studies will be included if more than 70% of the participants live in malaria-endemic regions) Studies assessing participants with or without anaemia and with or without malaria parasitaemia at baseline will be included Exclusion criteria Individuals not taking antifolate antimalarial medications for prevention or treatment of malaria Individuals living in non-malaria endemic areas Types of interventions Inclusion criteria Folic acid supplementation Form: in tablet, capsule, dispersible tablet at any dose, during administration, or periodically Timing: during, before, or after (within a period of four to six weeks) administration of antifolate antimalarials Iron-folic acid supplementation Folic acid supplementation in combination with co-interventions that are identical between the intervention and control groups. Co-interventions include: anthelminthic treatment; multivitamin or multiple micronutrient supplementation; 5-methyltetrahydrofolate supplementation. Exclusion criteria Folate through folate-fortified water Folic acid administered through large-scale fortification of rice, wheat, or maize Comparators Placebo No treatment No folic acid/different doses of folic acid Iron Types of outcome measures Primary outcomes Uncomplicated malaria (defined as a history of fever with parasitological confirmation; acceptable parasitological confirmation will include rapid diagnostic tests (RDTs), malaria smears, or nucleic acid detection (i.e. polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), etc.)) (WHO 2010). This outcome is relevant for patients without malaria, given antifolate antimalarials for malaria prophylaxis. Severe malaria (defined as any case with cerebral malaria or acute P. falciparum malaria, with signs of severity or evidence of vital organ dysfunction, or both) (WHO 2010). This outcome is relevant for patients without malaria, given antifolate antimalarials for malaria prophylaxis. Parasite clearance (any Plasmodium species), defined as the time it takes for a patient who tests positive at enrolment and is treated to become smear-negative or PCR negative. This outcome is relevant for patients with malaria, treated with antifolate antimalarials. Treatment failure (defined as the inability to clear malaria parasitaemia or prevent recrudescence after administration of antimalarial medicine, regardless of whether clinical symptoms are resolved) (WHO 2019). This outcome is relevant for patients with malaria, treated with antifolate antimalarials. Secondary outcomes Duration of parasitaemia Parasite density Haemoglobin (Hb) concentrations (g/L) Anaemia: severe anaemia (defined as Hb less than 70 g/L in pregnant women and children aged six to 59 months; and Hb less than 80 g/L in other populations); moderate anaemia (defined as Hb less than 100 g/L in pregnant women and children aged six to 59 months; and less than 110 g/L in others) Death from any cause Among pregnant women: stillbirth (at less than 28 weeks gestation); low birthweight (less than 2500 g); active placental malaria (defined as Plasmodium detected in placental blood by smear or PCR, or by Plasmodium detected on impression smear or placental histology). Search methods for identification of studies A search will be conducted to identify completed and ongoing studies, without date or language restrictions. Electronic searches A search strategy will be designed to include the appropriate subject headings and text word terms related to each intervention of interest and study design of interest (see Appendix 1). Searches will be broken down by these two criteria (intervention of interest and study design of interest) to allow for ease of prioritization, if necessary. The study design filters recommended by the Scottish Intercollegiate Guidelines Network (SIGN), and those designed by Cochrane for identifying clinical trials for MEDLINE and Embase, will be used (SIGN 2020). There will be no date or language restrictions. Non-English articles identified for inclusion will be translated into English. If translations are not possible, advice will be requested from the Cochrane Infectious Diseases Group and the record will be stored in the "Awaiting assessment" section of the review until a translation is available. The following electronic databases will be searched for primary studies. Cochrane Central Register of Controlled Trials. Cumulative Index to Nursing and Allied Health Literature (CINAHL). Embase. MEDLINE. Scopus. Web of Science (both the Social Science Citation Index and the Science Citation Index). We will conduct manual searches of ClinicalTrials.gov, the International Clinical Trials Registry Platform (ICTRP), and the United Nations Children's Fund (UNICEF) Evaluation and Research Database (ERD), in order to identify relevant ongoing or planned trials, abstracts, and full-text reports of evaluations, studies, and surveys related to programmes on folic acid supplementation in malaria-endemic areas. Additionally, manual searches of grey literature to identify RCTs that have not yet been published but are potentially eligible for inclusion will be conducted in the following sources. Global Index Medicus (GIM). African Index Medicus (AIM). Index Medicus for the Eastern Mediterranean Region (IMEMR). Latin American & Caribbean Health Sciences Literature (LILACS). Pan American Health Organization (PAHO). Western Pacific Region Index Medicus (WPRO). Index Medicus for the South-East Asian Region (IMSEAR). The Spanish Bibliographic Index in Health Sciences (IBECS) (ibecs.isciii.es/). Indian Journal of Medical Research (IJMR) (journals.lww.com/ijmr/pages/default.aspx). Native Health Database (nativehealthdatabase.net/). Scielo (www.scielo.br/). Searching other resources Handsearches of the five journals with the highest number of included studies in the last 12 months will be conducted to capture any relevant articles that may not have been indexed in the databases at the time of the search. We will contact the authors of included studies and will check reference lists of included papers for the identification of additional records. For assistance in identifying ongoing or unpublished studies, we will contact the Division of Nutrition, Physical Activity, and Obesity (DNPAO) and the Division of Parasitic Diseases and Malaria (DPDM) of the CDC, the United Nations World Food Programme (WFP), Nutrition International (NI), Global Alliance for Improved Nutrition (GAIN), and Hellen Keller International (HKI). Data collection and analysis Selection of studies Two review authors will independently screen the titles and abstracts of articles retrieved by each search to assess eligibility, as determined by the inclusion and exclusion criteria. Studies deemed eligible for inclusion by both review authors in the abstract screening phase will advance to the full-text screening phase, and full-text copies of all eligible papers will be retrieved. If full articles cannot be obtained, we will attempt to contact the authors to obtain further details of the studies. If such information is not obtained, we will classify the study as "awaiting assessment" until further information is published or made available to us. The same two review authors will independently assess the eligibility of full-text articles for inclusion in the systematic review. If any discrepancies occur between the studies selected by the two review authors, a third review author will provide arbitration. Each trial will be scrutinized to identify multiple publications from the same data set, and the justification for excluded trials will be documented. A PRISMA flow diagram of the study selection process will be presented to provide information on the number of records identified in the literature searches, the number of studies included and excluded, and the reasons for exclusion (Moher 2009). The list of excluded studies, along with their reasons for exclusion at the full-text screening phase, will also be created. Data extraction and management Two review authors will independently extract data for the final list of included studies using a standardized data specification form. Discrepancies observed between the data extracted by the two authors will be resolved by involving a third review author and reaching a consensus. Information will be extracted on study design components, baseline participant characteristics, intervention characteristics, and outcomes. For individually randomized trials, we will record the number of participants experiencing the event and the number analyzed in each treatment group or the effect estimate reported (e.g. risk ratio (RR)) for dichotomous outcome measures. For count data, we will record the number of events and the number of person-months of follow-up in each group. If the number of person-months is not reported, the product of the duration of follow-up and the number of children evaluated will be used to estimate this figure. We will calculate the rate ratio and standard error (SE) for each study. Zero events will be replaced by 0.5. We will extract both adjusted and unadjusted covariate incidence rate ratios if they are reported in the original studies. For continuous data, we will extract means (arithmetic or geometric) and a measure of variance (standard deviation (SD), SE, or confidence interval (CI)), percentage or mean change from baseline, and the numbers analyzed in each group. SDs will be computed from SEs or 95% CIs, assuming a normal distribution of the values. Haemoglobin values in g/dL will be calculated by multiplying haematocrit or packed cell volume values by 0.34, and studies reporting haemoglobin values in g/dL will be converted to g/L. In cluster-randomized trials, we will record the unit of randomization (e.g. household, compound, sector, or village), the number of clusters in the trial, and the average cluster size. The statistical methods used to analyze the trials will be documented, along with details describing whether these methods adjusted for clustering or other covariates. We plan to extract estimates of the intra-cluster correlation coefficient (ICC) for each outcome. Where results are adjusted for clustering, we will extract the treatment effect estimate and the SD or CI. If the results are not adjusted for clustering, we will extract the data reported. Assessment of risk of bias in included studies Two review authors (KSC, LFY) will independently assess the risk of bias for each included trial using the Cochrane 'Risk of bias 2' tool (RoB 2) for randomized studies (Sterne 2019). Judgements about the risk of bias of included studies will be made according to the recommendations outlined in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2021). Disagreements will be resolved by discussion, or by involving a third review author. The interest of our review will be to assess the effect of assignment to the interventions at baseline. We will evaluate each primary outcome using the RoB2 tool. The five domains of the Cochrane RoB2 tool include the following. Bias arising from the randomization process. Bias due to deviations from intended interventions. Bias due to missing outcome data. Bias in measurement of the outcome. Bias in selection of the reported result. Each domain of the RoB2 tool comprises the following. A series of 'signalling' questions. A judgement about the risk of bias for the domain, facilitated by an algorithm that maps responses to the signalling questions to a proposed judgement. Free-text boxes to justify responses to the signalling questions and 'Risk of bias' judgements. An option to predict (and explain) the likely direction of bias. Responses to signalling questions elicit information relevant to an assessment of the risk of bias. These response options are as follows. Yes (may indicate either low or high risk of bias, depending on the most natural way to ask the question). Probably yes. Probably no. No. No information (may indicate no evidence of that problem or an absence of information leading to concerns about there being a problem). Based on the answer to the signalling question, a 'Risk of bias' judgement is assigned to each domain. These judgements include one of the following. High risk of bias Low risk of bias Some concerns To generate the risk of bias judgement for each domain in the randomized studies, we will use the Excel template, available at www.riskofbias.info/welcome/rob-2-0-tool/current-version-of-rob-2. This file will be stored on a scientific data website, available to readers. Risk of bias in cluster randomized controlled trials For the cluster randomized trials, we will be using the RoB2 tool to analyze the five standard domains listed above along with Domain 1b (bias arising from the timing of identification or recruitment of participants) and its related signalling questions. To generate the risk of bias judgement for each domain in the cluster RCTs, we will use the Excel template available at https://sites.google.com/site/riskofbiastool/welcome/rob-2-0-tool/rob-2-for-cluster-randomized-trials. This file will be stored on a scientific data website, available to readers. Risk of bias in cross-over randomized controlled trials For cross-over randomized trials, we will be using the RoB2 tool to analyze the five standard domains listed above along with Domain 2 (bias due to deviations from intended interventions), and Domain 3 (bias due to missing outcome data), and their respective signalling questions. To generate the risk of bias judgement for each domain in the cross-over RCTs, we will use the Excel template, available at https://sites.google.com/site/riskofbiastool/welcome/rob-2-0-tool/rob-2-for-crossover-trials, for each risk of bias judgement of cross-over randomized studies. This file will be stored on a scientific data website, available to readers. Overall risk of bias The overall 'Risk of bias' judgement for each specific trial being assessed will be based on each domain-level judgement. The overall judgements include the following. Low risk of bias (the trial is judged to be at low risk of bias for all domains). Some concerns (the trial is judged to raise some concerns in at least one domain but is not judged to be at high risk of bias for any domain). High risk of bias (the trial is judged to be at high risk of bias in at least one domain, or is judged to have some concerns for multiple domains in a way that substantially lowers confidence in the result). The 'risk of bias' assessments will inform our GRADE evaluations of the certainty of evidence for our primary outcomes presented in the 'Summary of findings' tables and will also be used to inform the sensitivity analyses; (see Sensitivity analysis). If there is insufficient information in study reports to enable an assessment of the risk of bias, studies will be classified as "awaiting assessment" until further information is published or made available to us. Measures of treatment effect Dichotomous data For dichotomous data, we will present proportions and, for two-group comparisons, results as average RR or odds ratio (OR) with 95% CIs. Ordered categorical data Continuous data We will report results for continuous outcomes as the mean difference (MD) with 95% CIs, if outcomes are measured in the same way between trials. Where some studies have reported endpoint data and others have reported change-from-baseline data (with errors), we will combine these in the meta-analysis, if the outcomes were reported using the same scale. We will use the standardized mean difference (SMD), with 95% CIs, to combine trials that measured the same outcome but used different methods. If we do not find three or more studies for a pooled analysis, we will summarize the results in a narrative form. Unit of analysis issues Cluster-randomized trials We plan to combine results from both cluster-randomized and individually randomized studies, providing there is little heterogeneity between the studies. If the authors of cluster-randomized trials conducted their analyses at a different level from that of allocation, and they have not appropriately accounted for the cluster design in their analyses, we will calculate the trials' effective sample sizes to account for the effect of clustering in data. When one or more cluster-RCT reports RRs adjusted for clustering, we will compute cluster-adjusted SEs for the other trials. When none of the cluster-RCTs provide cluster-adjusted RRs, we will adjust the sample size for clustering. We will divide, by the estimated design effects (DE), the number of events and number evaluated for dichotomous outcomes and the number evaluated for continuous outcomes, where DE = 1 + ((average cluster size 1) * ICC). The derivation of the estimated ICCs and DEs will be reported. We will utilize the intra-cluster correlation coefficient (ICC), derived from the trial (if available), or from another source (e.g., using the ICCs derived from other, similar trials) and then calculate the design effect with the formula provided in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2021). If this approach is used, we will report it and undertake sensitivity analysis to investigate the effect of variations in ICC. Studies with more than two treatment groups If we identify studies with more than two intervention groups (multi-arm studies), where possible we will combine groups to create a single pair-wise comparison or use the methods set out in the Cochrane Handbook to avoid double counting study participants (Higgins 2021). For the subgroup analyses, when the control group was shared by two or more study arms, we will divide the control group (events and total population) over the number of relevant subgroups to avoid double counting the participants. Trials with several study arms can be included more than once for different comparisons. Cross-over trials From cross-over trials, we will consider the first period of measurement only and will analyze the results together with parallel-group studies. Multiple outcome events In several outcomes, a participant might experience more than one outcome event during the trial period. For all outcomes, we will extract the number of participants with at least one event. Dealing with missing data We will contact the trial authors if the available data are unclear, missing, or reported in a format that is different from the format needed. We aim to perform a 'per protocol' or 'as observed' analysis; otherwise, we will perform a complete case analysis. This means that for treatment failure, we will base the analyses on the participants who received treatment and the number of participants for which there was an inability to clear malarial parasitaemia or prevent recrudescence after administration of an antimalarial medicine reported in the studies. Assessment of heterogeneity Heterogeneity in the results of the trials will be assessed by visually examining the forest plot to detect non-overlapping CIs, using the Chi2 test of heterogeneity (where a P value of less than 0.1 indicates statistical significance) and the I2 statistic of inconsistency (with a value of greater than 50% denoting moderate levels of heterogeneity). When statistical heterogeneity is present, we will investigate the reasons for it, using subgroup analysis. Assessment of reporting biases We will construct a funnel plot to assess the effect of small studies for the main outcome (when including more than 10 trials). Data synthesis The primary analysis will include all eligible studies that provide data regardless of the overall risk of bias as assessed by the RoB2 tool. Analyses will be conducted using Review Manager 5.4 (Review Manager 2020). Cluster-RCTs will be included in the main analysis after adjustment for clustering (see the previous section on cluster-RCTs). The meta-analysis will be performed using the Mantel-Haenszel random-effects model or the generic inverse variance method (when adjustment for clustering is performed by adjusting SEs), as appropriate. Subgroup analysis and investigation of heterogeneity The overall risk of bias will not be used as the basis in conducting our subgroup analyses. However, where data are available, we plan to conduct the following subgroup analyses, independent of heterogeneity. Dose of folic acid supplementation: higher doses (4 mg or more, daily) versus lower doses (less than 4 mg, daily). Moderate-severe anaemia at baseline (mean haemoglobin of participants in a trial at baseline below 100 g/L for pregnant women and children aged six to 59 months, and below 110 g/L for other populations) versus normal at baseline (mean haemoglobin above 100 g/L for pregnant women and children aged six to 59 months, and above 110 g/L for other populations). Antimalarial drug resistance to parasite: known resistance versus no resistance versus unknown/mixed/unreported parasite resistance. Folate status at baseline: Deficient (e.g. RBC folate concentration of less than 305 nmol/L, or serum folate concentration of less than 7nmol/L) and Insufficient (e.g. RBC folate concentration from 305 to less than 906 nmol/L, or serum folate concentration from 7 to less than 25 nmol/L) versus Sufficient (e.g. RBC folate concentration above 906 nmol/L, or serum folate concentration above 25 nmol/L). Presence of anaemia at baseline: yes versus no. Mandatory fortification status: yes, versus no (voluntary or none). We will only use the primary outcomes in any subgroup analyses, and we will limit subgroup analyses to those outcomes for which three or more trials contributed data. Comparisons between subgroups will be performed using Review Manager 5.4 (Review Manager 2020). Sensitivity analysis We will perform a sensitivity analysis, using the risk of bias as a variable to explore the robustness of the findings in our primary outcomes. We will verify the behaviour of our estimators by adding and removing studies with a high risk of bias overall from the analysis. That is, studies with a low risk of bias versus studies with a high risk of bias. Summary of findings and assessment of the certainty of the evidence For the assessment across studies, we will use the GRADE approach, as outlined in (Schünemann 2021). We will use the five GRADE considerations (study limitations based on RoB2 judgements, consistency of effect, imprecision, indirectness, and publication bias) to assess the certainty of the body of evidence as it relates to the studies which contribute data to the meta-analyses for the primary outcomes. The GRADEpro Guideline Development Tool (GRADEpro) will be used to import data from Review Manager 5.4 (Review Manager 2020) to create 'Summary of Findings' tables. The primary outcomes for the main comparison will be listed with estimates of relative effects, along with the number of participants and studies contributing data for those outcomes. These tables will provide outcome-specific information concerning the overall certainty of evidence from studies included in the comparison, the magnitude of the effect of the interventions examined, and the sum of available data on the outcomes we considered. We will include only primary outcomes in the summary of findings tables. For each individual outcome, two review authors (KSC, LFY) will independently assess the certainty of the evidence using the GRADE approach (Balshem 2011). For assessments of the overall certainty of evidence for each outcome that includes pooled data from included trials, we will downgrade the evidence from 'high certainty' by one level for serious (or by two for very serious) study limitations (risk of bias, indirectness of evidence, serious inconsistency, imprecision of effect estimates, or potential publication bias).
Crider K ,Williams J ,Qi YP ,Gutman J ,Yeung L ,Mai C ,Finkelstain J ,Mehta S ,Pons-Duran C ,Menéndez C ,Moraleda C ,Rogers L ,Daniels K ,Green P ... - 《Cochrane Database of Systematic Reviews》
被引量: - 发表:1970年 -
User surveys support designing a prosthetic wrist that incorporates the Dart Thrower's Motion.
Davidson M ,Bodine C ,Weir RFF 《-》
被引量: - 发表:1970年 -
Hand Surgeons' Understanding of Partial Hand Prostheses: Results of a National Survey Study.
Graham EM ,Baschuk CM ,Atkins DJ ,Hutchinson L ,Duncan CC ,Mendenhall SD ... - 《-》
被引量: - 发表:1970年
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