An increasing number of health system researchers use systematic review to synthesize research evidence to inform the development of health policies at global and national levels. However, there are methodological challenges facing the health system research in undertaking systematic reviews of health policy literatures. This paper explored the constraints and promise of systematic review as a tool for evidence-based health system research in developing countries. It introduced the systematic review method and its evolution in health research over the past decades. The paper then discussed the definition of health system research, as system science, and contrasted its features/characteristics to those of medical research. It discussed and analyzed if the systematic review could be an effective tool for evidence-based health system research, particularly in developing countries. The paper concludes that the systematic review may be a very useful tool that can be used for evidence-based health system research to address specific policy issues; however, research on some health system/policy issues may not be appropriate to use the systematic review at all.
Objectives To assess the effects of alpha-glucosidase inhibitors in patients with type 2 diabetes mellitus. Method We searched The Cochrane Library, MEDLINE, EMBASE, Current Contents, LILACS, databases of ongoing trials, reference lists of reviews on the topic of alpha-glucosidase inhibitors and we contacted experts and manufacturers for additional trials. Date of most recent search: December 2003 (Current Contents) and April 2003 (other databases). Randomised controlled trials of at least 12 weeks duration comparing alpha-glucosidase inhibitor monotherapy in patients with type 2 diabetes with any other intervention and that included at least one of the following outcomes: mortality, morbidity, quality of life, glycemic control, lipids, insulin levels, body weight, adverse events. Two reviewers read all abstracts, assessed quality and extracted data independently. Discrepancies were resolved by consensus or by the judgement of a third reviewer. A statistician checked all extracted data entrance in the database. We attempted to contact all authors for data clarification. Results We included 41 trials (8130 participants), 30 investigated acarbose, seven miglitol, one trial voglibose and three trials compared different alpha-glucosidase inhibitors. Study duration was 24 weeks in most cases and only two studies lasted amply longer than one year. We found only few data on mortality, morbidity and quality of life. Acarbose had a clear effect on glycemic control compared to placebo: glycated haemoglobin –0.77% (95% confidence interval –0.90 to –0.64), fasting blood glucose –1.1 mmol/L (95% confidence interval –1.4 to –0.9), post-load blood glucose –2.32 mmol/L (95% confidence interval –2.73 to –1.92). The effect on glycated haemoglobin by acarbose was not dose-dependent. We found a decreasing effect on post-load insulin and no clinically relevant effects on lipids or body weight. Adverse effects were mostly of gastro-intestinal origin and dose dependent. Compared to sulphonylurea, acarbose decreased fasting and post-load insulin levels by –24.8 pmol/L (95% confidence interval –43.3 to –6.3) and –133.2 pmol/L (95% confidence interval –184.5 to –81.8) respectively and acarbose caused more adverse effects. Conclusions It remains unclear whether alpha-glucosidase inhibitors influence mortality or morbidity in patients with type 2 diabetes. Conversely, they have a significant effect on glycemic control and insulin levels, but no statistically significant effect on lipids and body weight. These effects are less sure when alpha-glucosidase inhibitors are used for a longer duration. Acarbose dosages higher than 50 mg TID offer no additional effect on glycated haemoglobin but more adverse effects instead. Compared to sulphonylurea, alpha-glucosidase inhibitors lower fasting and post-load insulin levels and have an inferior profile regarding glycemic control and adverse effects.
ObjectiveTo systematically evaluate the measurement properties of observational pain assessment scales for pediatric patients after surgery. MethodsThe PubMed, Embase, CINAHL, PsycArticles, and SinoMed databases were electronically searched to collect studies related to the objects from inception to April 13, 2024. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. And the quality of measurement properties was rated using updated criteria for good measurement properties to determine recommendation levels. ResultsA total of 26 studies were finally included involving 12 observational pain assessment scales for pediatric patients after surgery. None reported measurement error or cross-cultural validity. The overall content validity of all 12 scales was evaluated by reviewers, with measurement properties rated as sufficient or inconsistent. For internal consistency, due to insufficient or uncertain content validity, the evidence quality was low. Eight scales calculated internal consistency, among which CHEOPS, CHIPPS, COMFORT, FLACC, and NCCPC-PV scales had sufficient measurement properties with evidence quality of low or above, receiving Grade A recommendations. ConclusionCompared with other scales, CHEOPS, CHIPPS, COMFORT, FLACC, and NCCPC-PV scales demonstrated good measurement property evaluation with acceptable evidence quality and can be recommended for use. Other scales still require further improvement in measurement property validation.
Objective To assess the effect and safety of clinical nutritional supplementation with different patterns for treating systematic inflammatory response syndrome (SIRS). Methods Randomized controlled trials (RCTs) were identified from MEDLINE (1996 to Nov. 2004), EMBASE (1984 to Nov. 2002), Cochrane Controlled Trials Register (Issue 4, 2004), Chinese Cochrane Centre Database (Issue 4, 2004), CBMdisc (1978 to Nov. 2004). We handsearched related published and unpublished data and their references. All RCTs of nutritional interventions for SIRS were included. Data were extracted and evaluated by two reviewers independently with designed extraction form. RevMan 4.2.7 software was used for data analysis. Results Six RCTs involving 353 patients were included. All the results of meta-analysis were listed as the following: ① Mortality: compared with routine nutrition, one study showed that glutamine had a statistical difference with RR 0.67 and 95%CI 0.31 to 1.32. Compared with no treatment, one study showed selenium had a statistical difference with RR 1.19, 95%CI 0.59 to 2.41. ② Compared with routine nutrition, one study showed that glutamine had a statistical difference on reducing the ratio of nasocomial infection of SIRS with RR 0.5, 95%CI 0.27 to 0.91, but had no statistical difference on reducing the ratio of multiple organ dysfunction syndrome with RR 1.53, 95%CI 0.64 to 3.66. ③ Improvement of the critical condition of SIRS: compared with routine nutrition, one study showed that glutamine had a statistical differences with WMD 4.0, 95%CI 2.36 to 5.64; compared with high calorie intake, two studies showed low calorie intake had a statistical difference with WMD 4.9, 95%CI 1.76 to 8.04. ④ Reduction of the complication of hyperglycemia and hypertriglyceridemia: compared with high calorie intake, one study showed low calorie intake had statistical difference with WMD －0.70, 95%CI －1.20 to －0.20 and WMD －1.80, 95% CI －2.42 to －1.16 respectively and all P≤0.01. ⑤ Increasing of the plasma IgG concentration: compared with routine nutrition, two studies showed that glutamine had a statistical difference with WMD 4.20, 95% CI 2.23 to 6.16. ⑥ Increasing of the nitrogen balance, intestinal permeability, the level of plasma concentration of anlbumin, prealbumin and TRF: compared with control interventions, glutamine, low calorie intake, selenium supplementation and fructose-glucose-xylitol mixture showed no statistical difference. Conclusions Glutamine, low calorie intake, selenium supplementation, FGX mixture may decrease the complication of infection or metabolism and be better than the controlled interventions; but there is no benefit on reducing the rate of death result from SIRS compared with controlled interventions. The evidence of most RCTs with poor quality is too weak to draw a conclusion. More high quality trials are required.
ObjectiveTo evaluate the efficacy and safety of bisphosphonates in preventing and treating glucocorticoid induced osteoporosis.
MethodsDatabases including PubMed, EMbase, The Cochrane Library (Issue 1, 2016), CNKI, WanFang Data and VIP were searched to collect randomized controlled trials (RCTs) related bisphosphonates for the prevention and treatment of glucocorticoid induced osteoporosis from inception to January 2016. Two reviewers independently screened literature, extracted data, and evaluated the risk of bias of included studies. Meta-analysis was performed using RevMan 5.3 software.
ResultsA total of 20 RCTs were included, which involved 2 330 patients. The results of meta-analysis showed that, compared with the placebo group, the bisphosphonates group could significantly increase the bone mineral density (BMD) at lumbar and femoral neck (MD=3.70, 95%CI 2.65 to 4.75, P<0.000 01; MD=2.18, 95%CI 1.30 to 3.06, P<0.000 01), but the bisphosphonates group could not decrease the incidence rates of vertebral fracture or non-vertebral fracture (OR=0.66, 95%CI 0.38 to 1.16, P=0.15; OR=0.73, 95%CI 0.42 to 1.28, P=0.28). There were no significant differences in the incidence rates of total adverse reactions and total severe adverse reactions between the two groups (OR=0.89, 95%CI 0.62 to 1.28, P=0.53; OR=0.93, 95%CI 0.62 to 1.39, P=0.72).
ConclusionCurrent evidence shows that, compared with placebo, bisphosphonates canld effectively prevent and treat the decrease of bone mineral density of glucocorticoid induced osteoporosis, not decrease the incidence of fracture, but not increase the incidence of adverse reactions.
Objective To systematically review the health state utility values in patients with schizophrenia, and to provide references for subsequent studies on the health economics of schizophrenia. Methods The PubMed, EMbase, The Cochrane Library, Web of Science, CNKI, WanFang Data, and VIP databases were searched from inception to December 1st, 2021 to collect studies on health state utility values in patients with schizophrenia. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of the included studies. Meta-analysis was then performed by Stata 15.0 software. Results A total of 19 studies were included. Patients’ utility values were 0.68 (95%CI 0.59 to 0.77) for direct measures, and 0.77 (95%CI 0.75 to 0.80) and 0.66 (95%CI 0.61 to 0.70) for indirect measures with the EQ-5D-5L and EQ-5D-3L as the primary scales. Utility values varied with measures, tariffs, regions, and populations. Conclusion Studies on health state utility value in schizophrenia are diversified in measurement methods, showing high inter-study heterogeneity. Therefore, it is necessary to promote the study on utility value measurement in schizophrenia in China.
ObjectiveTo systematically review the efficacy and safety of early oxygen therapy for patients with acute myocardial infarction (AMI).
MethodsWe searched databases including PubMed, EMbase, The Cochrane Library (Issue 11, 2015) and CBM from inception to October 2015, to collect randomized controlled trials (RCTs) about early oxygen therapy for patients with AMI. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, meta-analysis was performed by using RevMan 5.3 software.
ResultsA total of 7 RCTs involving 1 388 patients were included. The results of meta-analysis showed that, there were no significant differences between the oxygen therapy group and the control group in mortality (OR=1.12, 95%CI 0.57 to 2.20, P=0.75), the incidence of major cardiovascular and cerebrovascular events (MACCE) (OR=1.00, 95%CI 0.46 to 2.18, P=1.00), the incidence of arrhythmia (OR=1.01, 95%CI 0.45 to 2.24, P=0.98) and the incidence of cardiac death (OR=0.53, 95%CI 0.17 to 1.67, P=0.28). But, the oxygen therapy group had higher risk of recurrent myocardial infarction (OR=5.50, 95%CI 1.44 to 20.99, P=0.01) and longer average hospital length of stay (MD=1.28, 95%CI 1.10 to 1.47, P<0.0001).
ConclusionThe efficacy of early oxygen therapy for patients with AMI is not clear, even may increase the risk of recurrent myocardial infarction and the average hospital length of stay. Due to the limited quantity and quality of include studies, more high quality studies are needed to verify the above conclusion.
Objective To assess the efficacy and safety of Shenmai injection for children with viral myocarditis. Methods All randomized and quasi-randomized controlled trials (RCTs and quasi-RCTs) of Shenmai injection for children with viral myocarditis were searched from CBM (1981 to November 2009), CNKI (1980 to November 2009) and VIP (1989 to November 2009), The Cochrane Library (Issue 1,2010), PubMed (1966 to 2009), EMbase (1966 to 2009). Cochrane systematic reviews Handbook 5.0.1 was taken as a reference to quality evaluation of the included studies, and the Cochrane Collaboration’s RevMan 5.0 software was used for data analyses. Results A total of 15 RCTs were included. The quality of the included trials was low. The result of meta-analyses showed that: (1) The effective rate (RR 1.16, 95%CI 1.07 to 1.25) and the ECG improvement rate (RR 1.55, 95%CI 1.25 to 1.93) in Shenmai injection group were better than those in the control group. CK and CK-MB in Shenmai injection were lower than those in the control group, but the AST level was similar in the two groups. (2) The effective rate (RR 1.12, 95%CI 1.01 to 1.25) and the ECG improvement rate (RR 1.35, 95%CI 1.07 to 1.70) in Shenmai injection group were better than those in the western medicine plus routine therapy (RT) group. CK, AST and LDH in Shenmai injection group were lower than those in the western medicine plus RT group, but CK-MB was similar in the two groups. (3) The effective rate (RR 1.26, 95%CI 1.12 to 1.42) in Shenmai injection plus RT and western medicine group was better than that in RT and western medicine group. CK and LDH-1 in Shenmai injection plus RT and western medicine group were lower than those in RT and western medicine group. Adverse reactions of Shenmai injection in 4 studies included mild rash, rubicundity and chest distress. No severe adverse reactions were reported. Conclusion The evidence currently available shows that Shenmai injection may have some effect on children with viral myocarditis, including improving the effective rate, reducing myocardial enzymes and improving the ECG improvement rate. However, because of the low methodological quality of the included trials, this conclusion needs to be interpreted cautionsly, and more well-designed, high-quality RCTs need to be performed.
ObjectiveTo systematically review mortality risk prediction models for acute type A aortic dissection (AAAD). MethodsPubMed, EMbase, Web of Science, CNKI, WanFang Data, VIP and CBM databases were electronically searched to collect studies of mortality risk prediction models for AAAD from inception to July 31th, 2021. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Systematic review was then performed. ResultsA total of 19 studies were included, of which 15 developed prediction models. The performance of prediction models varied substantially (AUC were 0.56 to 0.92). Only 6 studies reported calibration statistics, and all models had high risk of bias. ConclusionsCurrent prediction models for mortality and prognosis of AAAD patients are suboptimal, and the performance of the models varies significantly. It is still essential to establish novel prediction models based on more comprehensive and accurate statistical methods, and to conduct internal and a large number of external validations.
