Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 15 de 15
Filter
1.
J Clin Epidemiol ; 167: 111265, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38266740

ABSTRACT

OBJECTIVES: To investigate the prevalence of meta-analyses containing potentially redundant randomized controlled trials (RCTs) and the factors associated with the presence of redundancy. STUDY DESIGN AND SETTING: This is a cross-sectional study, based on a random sample of references (n = 4500) that were published during 2020 and 2021, indexed in PubMed, Embase, or the Cochrane Database of Systematic Reviews, and retrieved through comprehensive searches using terms about systematic reviews and meta-analysis. From each systematic review, one meta-analysis fulfilling all the following criteria, if available, was included in this study: (1) assessing the effect of the intervention on a primary outcome of the systematic review; (2) combining RCTs only. The primary outcome was prevalence of meta-analyses containing potentially redundant RCTs. Potentially redundant RCTs referred to the trials that started 1 year after the overall effect estimate from cumulative meta-analysis had been statistically robust, as determined by trial sequential analysis when appropriate. The number of potentially redundant trials (if any) in each eligible meta-analysis and the number of participants involved in those trials were documented and contrasted across groups. Logistic regression analysis was conducted to explore the factors associated with presence of potential redundancy. RESULTS: Of the 448 eligible meta-analyses, 57 (12.7%, 95% confidence interval (CI) 9.8-16.2%) contained potentially redundant RCTs. When limited to the 333 low-heterogeneity meta-analyses, the prevalence was 17.1% (95% CI 13.5-21.5%). The total number of potentially redundant RCTs was 295 (involving 85,385 participants), accounting for 38.5% of the RCTs (and 30.3% of the participants) included in the 57 meta-analyses. In these meta-analyses, the median number of potentially redundant RCTs and the participants involved were 2 (range: 1-50) and 352 (range: 17-26997), respectively. Potentially redundant RCTs were more likely to be present in the meta-analyses evaluating pharmaceutical intervention (odds ratio [OR] 2.31, 95% CI 1.16-4.49), assessing efficacy outcomes (OR 7.25, 95% CI 0.85-61.87), containing more than 5 RCTs (OR 6.47, 95% CI 3.22-12.99), or with the earliest RCT reporting statistically significant effect estimate (OR 5.30, 95% CI 2.64-10.64). CONCLUSION: This study found that 12.7% to 17.1% of recently published meta-analyses contained potentially redundant RCTs, highlighting the importance of conducting or examining systematic reviews of existing evidence to justify new RCTs. More importantly, the study identified some scenarios in which redundancy was more likely to occur and thus has implications for trialists, funding agencies, ethics committees, and journal editors.


Subject(s)
Research Design , Humans , Cross-Sectional Studies , Prevalence , Randomized Controlled Trials as Topic , Systematic Reviews as Topic
2.
Lancet Microbe ; 4(4): e236-e246, 2023 04.
Article in English | MEDLINE | ID: mdl-36868258

ABSTRACT

BACKGROUND: The efficacy of SARS-CoV-2 vaccines in preventing severe COVID-19 illness and death is uncertain due to the rarity of data in individual trials. How well the antibody concentrations can predict the efficacy is also uncertain. We aimed to assess the efficacy of these vaccines in preventing SARS-CoV-2 infections of different severities and the dose-response relationship between the antibody concentrations and efficacy. METHODS: We did a systematic review and meta-analysis of randomised controlled trials (RCTs). We searched PubMed, Embase, Scopus, Web of Science, Cochrane Library, WHO, bioRxiv, and medRxiv for papers published between Jan 1, 2020 and Sep 12, 2022. RCTs on the efficacy of SARS-CoV-2 vaccines were eligible. Risk of bias was assessed using the Cochrane tool. A frequentist, random-effects model was used to combine efficacy for common outcomes (ie, symptomatic and asymptomatic infections) and a Bayesian random-effects model was used for rare outcomes (ie, hospital admission, severe infection, and death). Potential sources of heterogeneity were investigated. The dose-response relationships of neutralising, spike-specific IgG and receptor binding domain-specific IgG antibody titres with efficacy in preventing SARS-CoV-2 symptomatic and severe infections were examined by meta-regression. This systematic review is registered with PROSPERO, CRD42021287238. FINDINGS: 28 RCTs (n=286 915 in vaccination groups and n=233 236 in placebo groups; median follow-up 1-6 months after last vaccination) across 32 publications were included in this review. The combined efficacy of full vaccination was 44·5% (95% CI 27·8-57·4) for preventing asymptomatic infections, 76·5% (69·8-81·7) for preventing symptomatic infections, 95·4% (95% credible interval 88·0-98·7) for preventing hospitalisation, 90·8% (85·5-95·1) for preventing severe infection, and 85·8% (68·7-94·6) for preventing death. There was heterogeneity in the efficacy of SARS-CoV-2 vaccines against asymptomatic and symptomatic infections but insufficient evidence to suggest whether the efficacy could differ according to the type of vaccine, age of the vaccinated individual, and between-dose interval (p>0·05 for all). Vaccine efficacy against symptomatic infection waned over time after full vaccination, with an average decrease of 13·6% (95% CI 5·5-22·3; p=0·0007) per month but can be enhanced by a booster. We found a significant non-linear relationship between each type of antibody and efficacy against symptomatic and severe infections (p<0·0001 for all), but there remained considerable heterogeneity in the efficacy, which cannot be explained by antibody concentrations. The risk of bias was low in most studies. INTERPRETATION: The efficacy of SARS-CoV-2 vaccines is higher for preventing severe infection and death than for preventing milder infection. Vaccine efficacy wanes over time but can be enhanced by a booster. Higher antibody titres are associated with higher estimates of efficacy but precise predictions are difficult due to large unexplained heterogeneity. These findings provide an important knowledge base for interpretation and application of future studies on these issues. FUNDING: Shenzhen Science and Technology Programs.


Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , COVID-19 Vaccines/therapeutic use , Asymptomatic Infections , COVID-19/prevention & control , SARS-CoV-2 , Immunoglobulin G , Randomized Controlled Trials as Topic
3.
JAMA Netw Open ; 6(3): e234219, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36951864

ABSTRACT

Importance: Systematic reviews can help to justify a new randomized clinical trial (RCT), inform its design, and interpret its results in the context of prior evidence. Objective: To assess trends and factors associated with citing (a marker of the use of) prior systematic reviews in RCT reports. Design, Setting, and Participants: This cross-sectional study investigated 737 Cochrane reviews assessing health interventions to identify 4003 eligible RCTs, defined as those included in an updated version but not in the first version of a Cochrane review and published 2 years after the first version of the Cochrane review was published. Main Outcomes and Measures: The primary outcome was the citation of prior systematic reviews, Cochrane or others, as determined by screening references of eligible RCTs. Factors that may be associated with the citation of prior systematic reviews were also examined. Results: Among 4003 eligible RCTs, 1241 studies (31.0%) cited Cochrane reviews, 1698 studies (42.4%) cited prior non-Cochrane reviews, and 2265 studies (56.6%) cited either type of systematic review or both; 1738 RCTs (43.4%) cited no systematic reviews. The percentage of RCTs citing prior Cochrane reviews, non-Cochrane reviews, and either or both types of review increased from 28 studies (15.3%), 46 studies (25.1%), and 65 studies (35.5%) of 183 RCTs before 2008 to 42 studies (40.8%), 65 studies (64.1%), and 73 studies (71.8%) of 102 RCTs since 2020, respectively; the annual increases were 1.9% (95% CI, 1.4%-2.3%), 3.3% (95% CI, 2.9%-3.7%), and 3.0% (95% CI, 2.5%-3.5%), respectively. The proportion of RCTs citating prior systematic reviews varied considerably across clinical specialties, ranging from 28 of 106 RCTs (26.4%) in ophthalmology to 386 of 553 RCTs (69.8%) in psychiatry (P < .001). RCTs with 100 participants or more (risk ratio [RR], 1.16; 95% CI, 1.03-1.30), nonindustry funding (RR, 1.43; 95% CI, 1.27-1.61), and authors from high-income countries (RR, 1.10; 95% CI, 1.03-1.17) were more likely to cite systematic reviews than those with fewer than 100 participants, industry funding, and authors from low- and middle-income countries, respectively. A journal requirement to cite systematic reviews was not associated with the likelihood of citing a systematic review. Conclusions and Relevance: This study found that the citation of prior systematic reviews in RCT reports improved over time, but approximately 40% of RCTs failed to do so. These findings suggest that reference to prior evidence for initiating, designing, and reporting RCTs should be further emphasized to assure clinical relevance, improve methodological quality, and facilitate interpretation of new results.


Subject(s)
Randomized Controlled Trials as Topic , Systematic Reviews as Topic , Humans
4.
BMC Med ; 21(1): 69, 2023 02 24.
Article in English | MEDLINE | ID: mdl-36829177

ABSTRACT

BACKGROUND: Redundant clinical trials waste resources and unnecessarily put patients at risk for harm. The objectives of the study were to assess redundant randomized clinical trials (RCTs) conducted in mainland China or the USA among patients with ST segment elevation myocardial infarction (STEMI) and estimate the harm to patients enrolled in redundant RCTs. METHODS: We searched bibliographic databases for eligible RCTs comparing a routine therapy with a placebo or no treatment among patients with STEMI in mainland China or the United States. The routine therapy for STEMI included reperfusion (percutaneous coronary intervention or fibrinolytic therapy), P2Y12 receptor inhibitors, statins, and anticoagulants. Redundant RCTs were defined as those initiated or continued recruiting new patients 1 year after the experimental intervention was established as routine therapy in clinical practice guidelines. Cumulative meta-analyses were conducted to confirm the efficacy of these routine therapies. The primary outcome was the number of extra major adverse cardiac events (MACEs) attributable to the deprivation of routine therapies among patients in the control groups of redundant RCTs-that is, the number of extra MACEs that could have been prevented had these patients received routine therapy. RESULTS: Nine hundred eighty-three eligible RCTs conducted in mainland China were identified, of which 775 (78.8%) were redundant. None of the five eligible RCTs conducted in the United States were redundant. All redundant RCTs have reiterated the benefits of routine therapies for patients with STEMI, while none were cited by the 2019 clinical practice guideline for the management of STEMI. The 18,819 patients in the control groups of redundant RCTs experienced 3305 (95% CI: 3169-3441) extra MACEs, including 1091 (1014-1165) deaths, 576 (519-633) recurrent myocardial infarctions, 31 (19-42) revascularizations, 39 (23-54) strokes, 744 (679-810) heart failures, and 823 (754-893) patients with recurrent or exacerbated angina pectoris. Cumulative meta-analyses confirmed the efficacy of the routine therapies among patients in mainland China and supported using practice guidelines to define redundant RCTs. CONCLUSIONS: Redundant RCTs conducted in mainland China have resulted in unnecessary MACEs among patients with STEMI. While the reasons behind redundant RCTs need to be further investigated, these results suggest potential research waste and violation of research ethics.


Subject(s)
Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction , Stroke , Humans , ST Elevation Myocardial Infarction/etiology , ST Elevation Myocardial Infarction/therapy , Treatment Outcome , Randomized Controlled Trials as Topic , Stroke/etiology , Percutaneous Coronary Intervention/adverse effects , Percutaneous Coronary Intervention/methods
5.
Metabolites ; 12(12)2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36557297

ABSTRACT

We conducted a scoping review to map available evidence about the health impact of gut microbiota-derived metabolites. We searched PubMed and Embase for studies that assessed the health impact of ten metabolites on any health condition: deoxycholate or deoxycholic acid (DCA), lithocholate or lithocholic acid (LCA), glycolithocholate or glycolithocholic acid, glycodeoxycholate or glycodeoxycholic acid, tryptamine, putrescine, d-alanine, urolithins, N-acetylmannosamine, and phenylacetylglutamine. We identified 352 eligible studies with 168,072 participants. Most (326, 92.6%) were case-control studies, followed by cohort studies (14, 4.0%), clinical trials (8, 2.3%), and cross-sectional studies (6, 1.7%). Most studies assessed the following associations: DCA on hepatobiliary disorders (64 studies, 7976 participants), colorectal cancer (19 studies, 7461 participants), and other digestive disorders (27 studies, 2463 participants); LCA on hepatobiliary disorders (34 studies, 4297 participants), colorectal cancers (14 studies, 4955 participants), and other digestive disorders (26 studies, 2117 participants); putrescine on colorectal cancers (16 studies, 94,399 participants) and cancers excluding colorectal and hepatobiliary cancers (42 studies, 4250 participants). There is a need to conduct more prospective studies, including clinical trials. Moreover, we identified metabolites and conditions for which systemic reviews are warranted to characterize the direction and magnitude of metabolite-disease associations.

6.
Adv Nutr ; 12(6): 2244-2254, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34157098

ABSTRACT

Lutein, zeaxanthin, and meso-zeaxanthin are the only carotenoids found in the human macula and may have a role in visual function. These carotenoids are reported to protect the retina, and thus vision, as antioxidants and by acting as a blue light filter. Our objective was to determine a minimum concentration of lutein/zeaxanthin intake that is associated with a statistically significant and/or clinically important change in macular pigment optical density (MPOD) among adults with healthy eyes. We searched Ovid MEDLINE, CENTRAL, and the Commonwealth of Agriculture Bureau for English-language studies through to July 2020. Two reviewers screened results to identify studies that evaluated supplements or dietary sources of lutein/zeaxanthin on MPOD among adults with healthy eyes. One reviewer extracted data and assessed strength of evidence, which was confirmed by a second reviewer. Two independent reviewers assessed the risk of bias. Meta-analyses were stratified by total lutein/zeaxanthin dose. We included 46 studies (N = 3189 participants; mean age = 43 y; 42% male). There was no statistically significant change in MPOD among studies evaluating <5 mg/d of total lutein/zeaxanthin intake which primarily assessed dietary interventions for 3-6 mo (pooled mean difference, 0.02; 95% CI: -0.01 to 0.05). The pooled mean increase in MPOD was 0.04 units (95% CI: 0.02 to 0.07) among studies evaluating 5 to <20 mg/d of lutein/zeaxanthin and was 0.11 units (95% CI: 0.06 to 0.16) among studies evaluating ≥20 mg/d of lutein/zeaxanthin for 3-12 mo. MPOD increased with lutein/zeaxanthin intake, particularly at higher doses, among adults with healthy eyes. The effects of lutein/zeaxanthin intake at doses <5 mg/d or from dietary sources is less clear. Increased lutein/zeaxanthin intake can help with maintaining ocular health. Future research is needed to determine the minimum dose and duration of lutein/zeaxanthin intake that is associated with a clinically important change in MPOD or visual function.


Subject(s)
Macula Lutea , Macular Pigment , Adult , Dietary Supplements , Female , Humans , Lutein , Male , Zeaxanthins
7.
BMJ ; 372: n48, 2021 02 02.
Article in English | MEDLINE | ID: mdl-33531350

ABSTRACT

OBJECTIVE: To identify redundant clinical trials evaluating statin treatment in patients with coronary artery disease from mainland China, and to estimate the number of extra major adverse cardiac events (MACEs) experienced by participants not treated with statins in those trials. DESIGN: Cross sectional study. SETTING: 2577 randomized clinical trials comparing statin treatment with placebo or no treatment in patients with coronary artery disease from mainland China, searched from bibliographic databases to December 2019. PARTICIPANTS: 250 810 patients with any type of coronary artery disease who were enrolled in the 2577 randomized clinical trials. MAIN OUTCOME MEASURES: Redundant clinical trials were defined as randomized clinical trials that initiated or continued recruiting after 2008 (ie, one year after statin treatment was strongly recommended by clinical practice guidelines). The primary outcome is the number of extra MACEs that were attributable to the deprivation of statins among patients in the control groups of redundant clinical trials-that is, the number of extra MACEs that could have been prevented if patients were given statins. Cumulative meta-analyses were also conducted to establish the time points when statins were shown to have a statistically significant effect on coronary artery disease. RESULTS: 2045 redundant clinical trials were identified published between 2008 and 2019, comprising 101 486 patients in the control groups not treated with statins for 24 638 person years. 3470 (95% confidence interval 3230 to 3619) extra MACEs were reported, including 559 (95% confidence interval 506 to 612) deaths, 973 (95% confidence interval 897 to 1052) patients with new or recurrent myocardial infarction, 161 (132 to 190) patients with stroke, 83 (58 to 105) patients requiring revascularization, 398 (352 to 448) patients with heart failure, 1197 (1110 to 1282) patients with recurrent or deteriorated angina pectoris, and 99 (95% confidence interval 69 to 129) unspecified MACEs. CONCLUSIONS: Of more than 2000 redundant clinical trials on statins in patients with coronary artery disease identified from mainland China, an extra 3000 MACEs, including nearly 600 deaths, were experienced by participants not treated with statins in these trials. The scale of redundancy necessitates urgent reform to protect patients.


Subject(s)
Coronary Artery Disease/drug therapy , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Randomized Controlled Trials as Topic/standards , China , Coronary Artery Disease/mortality , Cross-Sectional Studies , Humans , Randomized Controlled Trials as Topic/statistics & numerical data , Research Design/standards , Systematic Reviews as Topic
8.
J Clin Epidemiol ; 132: 10-17, 2021 04.
Article in English | MEDLINE | ID: mdl-33309887

ABSTRACT

BACKGROUND AND OBJECTIVE: To evaluate the association between the nature of findings and the switching of registered primary outcomes among randomized controlled trials (RCTs) from mainland China. METHODS: This is a retrospective cohort study. We retrieved RCTs from trial registries and identified the corresponding journal articles from bibliographic databases until August 2019. Trial registries and journal articles were compared to evaluate whether registered primary outcomes with negative findings were more likely to be switched to secondary outcomes in the subsequent journal articles than those with positive findings. RESULTS: Switching of registered primary outcomes occurred in 131 (45%) of 294 RCTs. A total of 450 registered primary outcomes were matched to 522 (37%) primary outcomes and 871 (63%) secondary outcomes in the journal articles. Among RCTs registered before they started, the odds of switching primary outcomes with negative findings were 2.64 (95% CI: 1.16-6.02) times the odds of switching those with positive findings. Among RCTs registered when they were ongoing, the odds of switching primary outcomes with negative findings were 8.84 (95% CI: 3.62-25.93) times the odds of switching those with positive findings. CONCLUSION: The nature of findings may play a role in how likely a prespecified primary outcome is switched subsequently.


Subject(s)
Pharmaceutical Preparations , Randomized Controlled Trials as Topic/methods , Randomized Controlled Trials as Topic/statistics & numerical data , Registries/statistics & numerical data , Research Design/statistics & numerical data , China , Cohort Studies , Humans , Retrospective Studies
9.
JAMA Netw Open ; 3(12): e2027104, 2020 12 01.
Article in English | MEDLINE | ID: mdl-33270124

ABSTRACT

Importance: Duplicate publications of randomized clinical trials are prevalent in the health-related literature. To date, few studies have assessed the interaction between duplicate publication and the language of the original publication. Objective: To assess the existence of duplicate publication and the extent to which duplicate publication is associated with the language of the original publication. Design, Setting, and Participants: In this retrospective cohort study, eligible randomized clinical trials were retrieved from trial registries, and bibliographic databases were searched to determine their publication status. Eligible randomized clinical trials were for drug interventions from January 1, 2008, to December 31, 2014. The search and analysis were conducted from March 1 to August 31, 2019. The trial registries were either primary registries recognized by the World Health Organization or the Drug Clinical Trial Registry Platform sponsored by the China Food and Drug Administration. Exposures: Individual randomized clinical trials with positive vs negative results. Main Outcomes and Measures: Journal articles were classified as main articles (determined by largest sample size and longest follow-up among all journal articles derived from that randomized clinical trial) and duplicates. The duplicates were classified into 4 types: (1) unreferenced subgroup analysis (article did not disclose itself as a subgroup analysis or reference its main article); (2) unreferenced republication (article did not disclose itself as a replicate of the main article or reference it); (3) unreferenced interim analysis (article did not disclose itself as an interim analysis or reference its main article); and (4) partial duplicate (article did not disclose its sharing a subset of participants with other articles or reference them). Results: Among 470 randomized clinical trials published by August 2019 as journal articles, 55 (11.7%) had 75 duplicates, of which 53 (70.7%) were cross-language duplicates. Of the 75 duplicates, 33 (44.0%) were unreferenced republications, 25 (33.3%) unreferenced subgroup analyses, 15 (20.0%) unreferenced interim analyses, and 2 (2.7%) partial duplicates. When the main article of a randomized clinical trial was published in Chinese, those with positive findings were 2.48 (95% CI, 1.08-5.71) times more likely to have subsequent duplicate publication than those with negative findings. Conclusions and Relevance: In this study, most duplicates were cross-language duplicates and the most common type was unreferenced republication of the main article. Duplicate publication bias exists when the main articles of randomized clinical trials were published in Chinese, potentially misleading readers and compromising journals and evidence synthesis.


Subject(s)
Duplicate Publications as Topic , Randomized Controlled Trials as Topic , Translating , China , Humans , Language
11.
BMJ Open ; 10(9): e038123, 2020 09 13.
Article in English | MEDLINE | ID: mdl-32928858

ABSTRACT

INTRODUCTION: Hepatitis B virus (HBV) remains a public health threat and the main route of transmission is from mother to child (MTCT). Tenofovir disoproxil fumarate (TDF) treatment can reduce MTCT of HBV although the optimal timing to attain undetectable HBV DNA concentrations at delivery is unknown. This protocol describes the procedures following early initiation of maternal TDF prior to 20 weeks gestation to determine efficacy, safety and feasibility of this approach in a limited-resource setting. METHODS AND ANALYSES: One hundred and seventy pregnant women from the Thailand-Myanmar border between 12 and <20 weeks gestational age will be enrolled into a one-arm, open-label, TDF treatment study with cessation of TDF 1 month after delivery. Sampling occurs monthly prenatal, at birth and at 1, 2, 4 and 6 months post partum. Measurement of tenofovir concentrations in maternal and cord plasma is anticipated in 10-15 women who have detectable HBV DNA at delivery and matched to 20-30 women with no detectable HBV DNA. Infant HBsAg status will be determined at 2 months of age and HBV DNA confirmed in HBsAg positive cases. Adverse events including risk of flare and adherence, based on pill count and questionnaire, will be monitored. Infants will receive HBV vaccinations at birth, 2, 4 and 6 months and hepatitis B immunoglobulin at birth if the mother is hepatitis B e antigen positive. Infant growth and neurodevelopment at 6 months will be compared with established local norms. ETHICS AND DISSEMINATION: This study has ethical approval by the Ethics Committee of the Faculty of Tropical Medicine, Mahidol University (FTM ECF-019-06), Johns Hopkins University (IRB no: 00007432), Chiang Mai University (FAM-2559-04227), Oxford Tropical Research Ethics Committee (OxTREC Reference: 49-16) and by the local Tak Community Advisory Board (TCAB-02/REV/2016). The article will be published as an open-access publication. TRIAL REGISTRATION NUMBER: NCT02995005, Pre-results.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Pregnancy Complications, Infectious , Antiviral Agents/therapeutic use , Child , DNA, Viral , Female , Hepatitis B/drug therapy , Hepatitis B/prevention & control , Hepatitis B virus/genetics , Hepatitis B, Chronic/drug therapy , Humans , Infant , Infant, Newborn , Infectious Disease Transmission, Vertical/prevention & control , Myanmar , Pregnancy , Pregnancy Complications, Infectious/drug therapy , Pregnancy Complications, Infectious/prevention & control , Tenofovir/therapeutic use , Thailand , Viral Load
12.
JAMA Netw Open ; 3(5): e205894, 2020 05 01.
Article in English | MEDLINE | ID: mdl-32463469

ABSTRACT

Importance: Language and indexing biases may exist among Chinese-sponsored randomized clinical trials (CS-RCTs). Such biases may threaten the validity of systematic reviews. Objective: To evaluate the existence of language and indexing biases among CS-RCTs on drug interventions. Design, Setting, and Participants: In this retrospective cohort study, eligible CS-RCTs were retrieved from trial registries, and bibliographic databases were searched to determine their publication status. Eligible CS-RCTs were for drug interventions conducted from January 1, 2008, to December 31, 2014. The search and analysis were conducted from March 1 to August 31, 2019. Primary trial registries were recognized by the World Health Organization and the Drug Clinical Trial Registry Platform sponsored by the China Food and Drug Administration. Exposures: Individual CS-RCTs with positive vs negative results (positive vs negative CS-RCTs). Main Outcomes and Measures: For assessing language bias, the main outcome was the language of the journal in which CS-RCTs were published (English vs Chinese). For indexing bias, the main outcome was the language of the bibliographic database where the CS-RCTs were indexed (English vs Chinese). Results: The search identified 891 eligible CS-RCTs. Four hundred seventy CS-RCTs were published by August 31, 2019, of which 368 (78.3%) were published in English. Among CS-RCTs registered in the Chinese Clinical Trial Registry (ChiCTR), positive CS-RCTs were 3.92 (95% CI, 2.20-7.00) times more likely to be published in English than negative CS-RCTs; among CS-RCTs in English-language registries, positive CS-RCTs were 3.22 (95% CI, 1.34-7.78) times more likely to be published in English than negative CS-RCTs. These findings suggest the existence of language bias. Among CS-RCTs registered in ChiCTR, positive CS-RCTs were 2.89 (95% CI, 1.55-5.40) times more likely to be indexed in English bibliographic databases than negative CS-RCTs; among CS-RCTs in English-language registries, positive CS-RCTs were 2.19 (95% CI, 0.82-5.82) times more likely to be indexed in English bibliographic databases than negative CS-RCTs. These findings support the existence of indexing bias. Conclusions and Relevance: This study suggests the existence of language and indexing biases among registered CS-RCTs on drug interventions. These biases may distort evidence synthesis toward more positive results of drug interventions.


Subject(s)
Bias , Databases, Bibliographic/statistics & numerical data , Drug Therapy , Language , Randomized Controlled Trials as Topic/statistics & numerical data , Registries/statistics & numerical data , China , Databases, Bibliographic/standards , Humans , Negative Results/statistics & numerical data , Periodicals as Topic/statistics & numerical data , Publication Bias/statistics & numerical data , Registries/standards , Retrospective Studies
13.
Qual Life Res ; 26(8): 1969-2010, 2017 08.
Article in English | MEDLINE | ID: mdl-28315178

ABSTRACT

PURPOSE: To identify currently available patient-reported outcome measures (PROMs) used in patients with foot or ankle diseases; and to critically appraise, compare and synthesize the psychometric evidence for the identified PROMs. METHODS: Literature searches were performed in Medline and EMBASE from their inception to January 25th, 2016. Methodological quality was evaluated using the COSMIN checklist. The final rating of the methodological quality of each study for each property was the lowest rating among the items within that property. The psychometric evidence of the properties investigated in the included articles was assessed using the quality criteria established by Terwee et al. The methodological quality ratings and psychometric evidence assessments were synthesized using the method first proposed by Schellingerhout et al. RESULTS: In total, 3077 articles were identified by the literature search, from which 115 studies investigating 50 PRO instruments were included in the review process. The Foot Function Index (FFI) was the most explored instrument, while the Manchester-Oxford Foot Questionnaire (MOXFQ) demonstrated the best properties. CONCLUSION: Most PROMs on foot and ankle diseases have limited evidence for their psychometric properties. The MOXFQ, with the highest overall ratings, could be a useful PROM for evaluating patients with foot or ankle diseases, based on current available evidence. More research is needed to improve the quality of the standards used to assess PROMs and the studies making these assessments.


Subject(s)
Ankle/pathology , Foot/pathology , Patient Reported Outcome Measures , Psychometrics/methods , Quality of Life/psychology , Adolescent , Adult , Aged , Aged, 80 and over , Humans , Middle Aged , Surveys and Questionnaires , Young Adult
14.
Hum Vaccin Immunother ; 11(8): 2061-7, 2015.
Article in English | MEDLINE | ID: mdl-26090956

ABSTRACT

Vaccination in prevention mother-to-child transmission (PMTCT) of hepatitis B has been recommended since plasma-derived hepatitis B vaccines became available in China in 1986; however, less study evaluated practice effectiveness of PMTCT systematically. We conducted a prospective survey to evaluate the effectiveness of PMTCT practices in 3 provinces of southern China. We selected prefectures with low timely birth dose coverage in Yunnan, Guangxi, and Hunan provinces. Infants born to HBsAg positive mothers were evaluated at 7-12 months of age. We tested hepatitis B virus (HBV) surface antigen (HBsAg) and HBV e antigen (HBeAg) of mothers and tested HBsAg of infants born to HBsAg positive mothers using Enzyme-linked Immunosorbent Assay (ELISA) at provincial CDC laboratories. We used logistic regression analysis to analyze the risk factors for HBV infection. Among 3,094 infants born to HBsAg positive mothers, 172 were positive for HBsAg (5.6%). HBeAg status of pregnant women, timely birth dose (TBD) of hepatitis B vaccine were major predictors for HBV infection of infants. PMTCT practices greatly reduced the prevalence of HBsAg among infants born to HBsAg positive mothers China. However, the effectiveness of strategies used in PMTCT varied. HBsAg screening for pregnant women, monitoring of infants born to HBsAg positive mother should be enhanced to evaluate the effectiveness of program.


Subject(s)
Hepatitis B Surface Antigens/blood , Hepatitis B e Antigens/blood , Hepatitis B/prevention & control , Hepatitis B/transmission , Infectious Disease Transmission, Vertical/prevention & control , Adult , China/epidemiology , Enzyme-Linked Immunosorbent Assay , Female , Hepatitis B/epidemiology , Humans , Infant , Infant, Newborn , Male , Prevalence , Prospective Studies , Risk Factors
15.
Hum Vaccin Immunother ; 10(10): 2983-91, 2014.
Article in English | MEDLINE | ID: mdl-25483678

ABSTRACT

OBJECTIVE: The aim of the study was to estimate long-term cost­effectiveness of a hepatitis B vaccination catch-up program among children born between 1994 and 2001 (when they were 8­15 y old) in Shandong province, China, to provide information for nationwide evaluation and future policy making. METHODS: We determined the cost-effectiveness of the catch-up program compared with the status quo (no catch-up program). We combined a Decision Tree model and a Markov model to simulate vaccination and clinical progression after hepatitis B virus (HBV) infection. Parameters in the models were from the literature, a field survey, program files, and the National Notifiable Disease Reporting System (NNDRS). The incremental cost­effectiveness ratio (ICER) was used to compare the 2 alternative strategies. One-way sensitivity analysis, 2-way sensitivity analysis, and probability sensitivity analysis were used to assess parameter uncertainties. RESULTS: The catch-up program was dominant compared with the status quo. Using a total of 5.53 million doses of vaccines, the catch-up program could prevent 21,865 cases of symptomatic acute hepatitis B, 3,088 carrier states with positive hepatitis B surface antigen (HBsAg), and 812 deaths due to HBV infection. The catch-up program could add 28,888 quality-adjusted life years (QALYs) and save $192.01 million in the targeted population in the future. The models were robust, considering parameter uncertainties. CONCLUSION: The catch-up program in Shandong province among children born between 1994 and 2001 was 'very cost-saving.' It could save life years and reduce total future costs. Our study supported the desirability and impact of such a catch-up program throughout China.


Subject(s)
Cost-Benefit Analysis , Hepatitis B Vaccines/economics , Hepatitis B/prevention & control , Immunization Programs/economics , Mass Vaccination/economics , Adolescent , Child , China , Female , Hepatitis B/immunology , Hepatitis B Vaccines/therapeutic use , Hepatitis B virus/immunology , Humans , Male , Markov Chains , Quality-Adjusted Life Years
SELECTION OF CITATIONS
SEARCH DETAIL
...