***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: I SHALL discuss the combination of estimates of relative prevalence or incidence , commonly referred to as relative risk , obtained from retrospective 2 X 2 tables . Barnet Woolf ' described the method in 1954 and J. B. S. Haldane2 introduced some modifications shortly afterward in the Annals of Human Genetics . Figure 1 shows how  retrospective case and control data  may be classified . There are usually some background classes based on age , sex , race , occupation , and the like . Within each such class , individuals are further classified into a 2 X 2 table according to the presence or absence of the disease being studied and the presence or absence of a defined characteristic of focal interest . For any single 2 X 2 table , Cornfield3 has shown a simple way to estimate the risk of disease among those wvith the characteristic , relative to the risk of disease among those without the characteristic . This is done , as illustrated below Figure 1 , by taking the ratio of diagonal products of the cell frequencies . This is a maximum likelihood estimate of the relative risk of disease in the parent population , provided that it is assumed that the cases and controls have been selected at r and om and that cases comprise a negligible portion of the population . It is also possible to obtain a combined , unconditioned , maximum likelihood estimate of relative risk based on all of the 2 X 2 tables . However , the method is time-consuming , involving the iterative solution of sets of quadratic equations . Unless such a method is programed for the computer , I feel that the less tedious procedure to be described is adequate for most practical purpose s. Strictly speaking , the maximum likelihood estimate just described has infinite bias and it is positively skewed . To help remedy these defects , the number , 1/2 , is added to each cell frequency before obtaining the ratio of diagonal products ; furthermore , the natural logarithm of this ratio is taken . The result ing value is an estimate of natural log relative risk . Woolf pointed out that the logarithmic transformation tends to remove skew and Haldane showed that of all possible numbers which might be added to or subtracted from the cell frequencies , 1/2 is the number which reduces the bias of the estimate to a minimum . This estimate of log relative risk is shown in the first column of Figure 2 . The estimated Background The approximately 1100 medical journals now active in China are publishing a rapidly increasing number of research reports , including many studies identified by their authors as r and omized controlled trials . It has been noticed that these reports mostly present positive results , and their quality and authenticity have consequently been called into question . We investigated the adequacy of r and omization  of clinical trials published in recent years in China to determine how many of them met acceptable st and ards for allocating participants to treatment groups . Methods The China National Knowledge Infrastructure electronic data base was search ed for reports of r and omized controlled trials on 20 common diseases published from January 1994 to June 2005 . From this sample , a subset of trials that appeared to have used r and omization methods was selected . Twenty-one investigators trained in the relevant knowledge , communication skills and quality control issues interviewed the original authors of these trials about the participant r and omization methods and related quality -control features of their trials . Results From an initial sample of 37,313 articles identified in the China National Knowledge Infrastructure data base , we found 3137 apparent r and omized controlled trials . Of these , 1452 were studies of conventional medicine ( published in 411 journals ) and 1685 were studies of traditional Chinese medicine ( published in 352 journals ) . Interviews with the authors of 2235 of these reports revealed that only 207 studies adhered to accepted methodology for r and omization and could on those grounds be deemed authentic r and omized controlled trials ( 6.8 % , 95 % confidence interval 5.9–7.7 ) . There was no statistically significant difference in the rate of authenticity between r and omized controlled trials of traditional interventions and those of conventional interventions . R and omized controlled trials conducted at hospitals affiliated to medical universities were more likely to be authentic than trials conducted at level 3 and level 2 hospitals ( relative risk 1.58 , 95 % confidence interval 1.18–2.13 , and relative risk 14.42 , 95 % confidence interval 9.40–22.10 , respectively ) . The likelihood of authenticity was higher in level 3 hospitals than in level 2 hospitals ( relative risk 9.32 , 95 % confidence interval 5.83–14.89 ) . All r and omized controlled trials of pre-market drug clinical trial were authentic by our criteria . Of the trials conducted at university-affiliated hospitals , 56.3 % were authentic ( 95 % confidence interval 32.0–81.0 ) . Conclusion Most reports of r and omized controlled trials published in some Chinese journals lacked an adequate description of r and omization . Similarly , most so called ' r and omized controlled trials ' were not real r and omized controlled trials owing toa lack of adequate underst and ing on the part of the authors of rigorous clinical trial design . All r and omized controlled trials of pre-market drug clinical trial included in this research were authentic . R and omized controlled trials conducted by authors in high level hospitals , especially in hospitals affiliated to medical universities had a higher rate of authenticity . That so many non-r and omized controlled trials were published as r and omized controlled trials reflected the fact that peer review needs to be improved and a good practice guide for peer review including how to identify the authenticity of the study urgently needs to be developed OBJECTIVE To determine whether clinical trials originating in certain countries always have positive results . DATA SOURCES Abstract s of trials from Medline ( January 1966-June 1995 ) . STUDY SELECTION Two separate studies were conducted . The first included trials in which the clinical outcome of a group of subjects receiving acupuncture  was compared to that of a group receiving placebo , no treatment , or a nonacupuncture intervention . In the second study , r and omized or controlled trials of interventions other than  acupuncture  that were published in China , Japan , Russia/USSR , or Taiwan were compared to those published in Engl and . DATA EXTRACTION Blinded review ers determined inclusion and outcome and separately classified each trial by country of origin . DATA SYNTHESIS In the study of acupuncture  trials , 252 of 1085 abstract s met the inclusion criteria . Research conducted in certain countries was uniformly favorable to acupuncture ; all trials originating in China , Japan , Hong Kong , and Taiwan were positive , as were 10 out of 11 of those published in Russia/USSR . In studies that examined interventions other than acupuncture , 405 of 1100 abstract s met the inclusion criteria . Of trials published in Engl and , 75 % gave the test treatment as superior to control . The results for China , Japan , Russia/USSR , and Taiwan were 99 % , 89 % , 97 % , and 95 % , respectively . No trial published in China or Russia/USSR found a test treatment to be ineffective . CONCLUSIONS Some countries publish unusually high proportions of positive results . Publication bias is a possible explanation . Research ers undertaking systematic review s should consider carefully how to manage data from these countries BACKGROUND We conducted a r and omized study to determine whether any of three chemotherapy regimens was superior to cisplatin and paclitaxel in patients with advanced non-small-cell lung cancer . METHODS A total of 1207 patients with advanced non-small-cell lung cancer were r and omly assigned to a reference regimen of cisplatin and paclitaxel or to one of three experimental regimens : cisplatin and gemcitabine , cisplatin and docetaxel , or carboplatin and paclitaxel . RESULTS The response rate for all 1155 eligible patients was 19 percent , with a median survival of 7.9 months ( 95 percent confidence interval , 7.3 to 8.5 ) , a 1-year survival rate of 33 percent ( 95 percent confidence interval , 30 to 36 percent ) , and a 2-year survival rate of 11 percent ( 95 percent confidence interval , 8 to 12 percent ) . The response rate and survival did not differ significantly between patients assigned to receive cisplatin and paclitaxel and those assigned to receive any of the three experimental regimens . Treatment with cisplatin and gemcitabine was associated with a significantly longer time to the progression of disease than was treatment with cisplatin and paclitaxel but was more likely to cause grade 3 , 4 , or 5 renal toxicity ( in 9 percent of patients , vs. 3 percent of those treated with cisplatin plus paclitaxel ) . Patients with a performance status of 2 had a significantly lower rate of survival than did those with a performance status of 0 or 1 . CONCLUSIONS None of four chemotherapy regimens offered a significant advantage over the others in the treatment of advanced non-small-cell lung cancer PURPOSE This r and omized trial was design ed to determine whether paclitaxel plus carboplatin ( PC ) offered a survival advantage over vinorelbine plus cisplatin ( VC ) for patients with advanced non -- small-cell lung cancer . Secondary objectives were to compare toxicity , tolerability , quality of life ( QOL ) , and re source utilization . PATIENTS AND METHODS Two hundred two patients received VC ( vinorelbine 25 mg/m(2)/wk and cisplatin 100 mg/m(2)/d , day 1 every 28 days ) and 206 patients received PC ( paclitaxel 225 mg/m(2 ) over 3 hours with carboplatin area under the curve of 6 , day 1 every 21 days ) . Patients completed QOL question naires at baseline , 13 weeks , and 25 weeks . Re source utilization forms were completed at five time points through 24 months . RESULTS Patient characteristics were similar between the groups . The objective response rate was 28 % in the VC arm and 25 % in the PC arm . Median survival was 8 months in both arms , with 1-year survival rates of 36 % and 38 % , respectively . Grade 3 and 4 leukopenia ( P = .002 ) and neutropenia ( P = .008 ) occurred more frequently on the VC arm . Grade 3 nausea and vomiting were higher on the VC arm ( P = .001 , P = .007 ) , and grade 3 peripheral neuropathy was higher on the PC arm ( P < .001 ) . More patients on the VC arm discontinued therapy because of toxicity ( P = .001 ) . No difference in QOL was observed . Overall costs on the PC arm were higher than on the VC arm because of drug costs . CONCLUSION PC is equally efficacious as VC for the treatment of advanced non -- small-cell lung cancer .  PC is less toxic and better tolerated but more expensive than VC . New treatment strategies should be pursued OBJECTIVE To observe the clinical therapeutic effect and mechanism of Yiqi Yangyin Jiedu Decoction ( YYJD , a Chinese herbal recipe for strengthening qi , nourishing yin and removing toxic substance , consisting of milkvetch root 30 g , glehnia root 30 g , asparagus root 15 g , lilyturf root 15 g , grossy privet fruit 12 g , spikemoss herb 30 g , Chinese sage herb 30 g , manyleaf paris rhizome 30 g , etc . ) in treating patients with advanced nonsmall cell lung cancer ( NSCLC ) . METHODS Sixty patients with advanced lung cancer of qi-yin deficiency syndrome were r and omized into three groups : the TCM group ( A ) treated with YYJD , the chemotherapy group ( B ) treated by chemotherapy with NP or GP protocol , and the combined treated group ( C ) treated with YYJD and chemotherapy in combination . The efficacy was evaluated after two cycles of treatment . RESULTS The total effective rate for alleviating qi-yin deficiency syndrome in group A was 80 % , significantly higher than that in Group C and B ( 35 % and 20 % , P < 0.01 ) respectively . The KPS increasing and stabilizing rate in Group A and C was 90 % and 85 % respectively , significantly higher than that in Group B ( 75 % ) , and difference between A and B was significant ( P < 0.05 ) . In Group C after treatment , CD(3)+ showed a rising trend ( P = 0.05 ) , different to that in Group A and B ( P < 0.05 and P < 0.01 ) ; CD(4)+ significantly increased ( P < 0.05 ) and CD(4)+/CD(8)+ ratio showed increasing trend ( P = 0.06 ) , while in Group B both were decreased significantly , showed significantly difference ( P < 0.05 ) . CD(8)+ CD(28)+ significantly increased after treatment in Group A and C ( P < 0.01 and P < 0.05 ) , but showed decreasing trend ( P = 0.06 ) in Group B , significant difference was shown between B and C ( P < 0.05 ) . CONCLUSION YYJD can ameliorate the qi-yin deficiency syndrome evidently in advance lung cancer patients ; improve their quality of life , the mechanism might be by way of enhancing T-lymphocyte activity and killer T-cell function , to elevate the T-cell mediated immunity in a round way OBJECTIVE To observe the regulatory effect of Jianpi Wenshen Recipe ( JPWS ) , a Chinese herbal preparation for strengthening Pi and warming Shen , combined with chemotherapy on the level of estradiol ( E2 ) in patients with mid-late non-small cell lung cancer ( NSCLC ) , and to analyse the relationship between the changes of estradiol and tumor size . METHODS Fifty-one NSCLC patients were r and omized into three groups : 1 
    Output:
    
We found a large treatment effect of adding astragalus-based herbal treatment to st and ard chemotherapy regimens .