Some risks affecting the quality of published systematic reviews and in our teaching practice were listed and compared with the correct concept. The current problems include misunderstanding of the relationship of meta-analysis and systematic review, applying meta-analysis and assessing heterogeneity, randomization, allocate concealment, and how to make inclusion and exclusion criteria, etc. This paper aims to help Chinese reviewers improve the quality of their systematic reviews.
Objective To assess the benefits and harms of traditional Chinese medicine in the treatment of postmenopausal osteoporosis. Methods We electronically searched MEDLINE (1966-2003), EMBASE (1974-2003), Controlled Trials Register and The National Research Register, The Cochrane Library Issue 4, 2003, CBM disc, VIP, CNKI, and CMCC. We also handsearched some related journals. The search was conducted in Nov., 2003. The quality of included randomized controlled trials was evaluated and meta-analysis was conducted by RevMan 4.2.2. Results We identified 33 studies including 2 337 patients and 27 traditional Chinese medicines. Some traditional Chinese medicines alone or integrated Chinese and Western medicine may be effective for improving patients’ bone mineral density, serum oestradiol and serum calcium. For example, Compared with placebo, Bushen Yigu soft extraction with WMD 0.76, 95% confidence interval 0.65 to 0.87, Bushen Qianggu capsule with WMD 39.94, 95% confidence interval 35.12 to 44.76 were effective for improving the level of serum oestradiol.There were no confirmed results of the other traditional Chinese medicines because of the small number of studies or inconsistent conclusions among studies. We didn’t find obvious side effects. Conclusions Some traditional Chinese medicines may be effective for treating postmenopausal osteoporosis. Due to the limited evidence identified, we can not draw a firm conclusion. More randomised controlled trials of high quality are needed for ber evidence.
Objective To determine the efficacy of radioisotopes to control metastasic pain in patients with tumor bone metastases and complications due to bone metastases (hypercalcaemia, bone fracture and spinal cord compression). The effectiveness of radioisotopes in relation to patient survival and adverse effects were also assessed. Methods MEDLINE (1966 to April 2005),EMBASE (1966 to April 2005), The Cochrane Library (Issue 1, 2005) and CBMdisc (1979 to April 2005) were searched for randomized controlled trials (RCTs). Data were extracted by two reviewers using a designed extraction form. The quality of included RCTs was critically assessed. RevMan 4.2 software was used for data analysis. Results Four RCTs were included. The results of meta-analysis showed that small dose of radioisotopes couldn’t control metastatic pain in short term(2 months) with relative risk (RR) 1.13, 95%confidence interval (CI) 0.34 to 3.76, but large dose can significantly control metastatic pain in medium term(6 month) with RR 1.90, 95％CI 1.23 to 2.92; no evidence was available to assess long term(≥12 months) effects. No study provided data on quality of life, mortality, bone metastatic complications (hypercalcaemia, bone fracture) and analgesic use etc. Leukocytopenia and thrombocytopenia were secondary effects associated with the administration of radioisotopes. The incidences of leukocytopenia and thrombocytopenia were significantly greater in patients treated by radioisotopes with RR 8.28, 95％CI 2.24 to 30.67, and RR 3.70, 95％CI 1.59 to 9.04, respectively. Conclusions There is some evidence indicating that large dose of radioisotopes can relieve metastatic bone pain over one to six months, but adverse effects, particularly leukocytopenia and thrombocytopenia, have also been experienced.
Objective To evaluate the quality of controlled trials on 131I therapy for thyroglobulin positive and radioactive iodine negative metastases（131I WBS-/Tg+）. Methods We electronically searched MEDLINE (1966 to Mar. 2004), EMBASE (1984 to 2003), The Cochrane Central Register of Controlled Trial, CENTRAL (Issue 2, 2004), CBMdisc (1978 to 2004) and CNKI (1994 to 2004), and handsearched 5 radiotherapy and endocrinology journals (Jan. 1980 to Apr. 2003). The methodological quality of included studies was assessed by using quality assessment criteria of the Cochrane systematic review guideline. Results Three non-randomized controlled trials were included. One was historical controlled trial, and two prospective trials. The sample sizes of three trials were 26, 60 and 70 respectively without mentioning the calculation base. The comparability of baseline was mentioned but not comparable across the trials. No double blind studies were used in the assessment of 131I efficacy. The time of follow-up varied from 2 to 15 years. None studies mentioned the side effects of 131I therapy for 131I WBS-/Tg+ metastases. Only two studies applied statistical methods properly. Conclusions Problems about allocation of groups, double blind, sample size, and follow-up period continue to exist in published controlled trials. RCT or prospective controlled trials of high quality are urgently needed in order to define the efficacy and safety of 131I therapy for 131I WBS-/Tg+ metastases.
Objective To evaluate the efficacy of artificial total disc replacement for lumbar degenerative disc disease compared with lumbar fusion and other treatment. Methods We conducted electronic searching on The Cochrane Library (Issue 2, 2004) and Specialized Trials Register of Cochrane Back Group, MEDLINE (1966 to 2004)，EMBASE (1980 to 2004) and CBMdisk (2003), some Chinese Journals were handsearched, and researchers in the field were contacted. Data were extracted and evaluated by two reviewers independently. The quality evaluation of studies and data analysis followed the methods of The Cochrane Collaboration. Results Three studies including 152 patients met the inclusion criteria. Two studies used ProDisc Ⅱ, while the other one used SB-Ⅲ. The patients who received the disc replacement reported reduced pain and improved function in early postoperative period, better satisfaction rates at month 6 post operation; complications of operation were reported in two randomized controlled trials. Conclusions The quality of the included trials is inadequate to draw any conclusion about the efficacy of artificial total disc replacement. More trials with high quality on methodology are needed. Artificial discs could preserve motion of diseased level in the short term. Protection of adjacent levels can only be assessed when large studies with long term follow-up are conducted.
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.