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At least 667 records · Page 37Linked to original sources
PubMed2005

Correlations between physiological variables and performance in high level cross country off road cyclists.

OBJECTIVES: To examine the relations between maximal and submaximal indices of aerobic fitness and off road cycling performance in a homogeneous group of high level mountain bikers. METHODS: 12 internationally competitive mountain bikers completed the study. Maximum oxygen uptake (Vo(2max)), peak power output (PPO), power output (PO), and oxygen uptake (Vo(2)) at first (VT) and second (RCT) ventilatory thresholds were measured in the laboratory, and correlated with race time during a cross country circuit race. RESULTS: The only physiological indices of aerobic fitness correlated with off road cycling performance were PO and Vo(2) at RCT when normalised to body mass (r = -0.63 and r = -0.66, respectively; p<0.05). VT, Vo(2max), and PPO were not correlated to performance in this homogeneous group of high level mountain bikers. CONCLUSIONS: The results of this study suggest that submaximal indices of aerobic fitness such as PO and Vo(2) at RCT are more important determinants of off road cycling performance than maximal indices such as PPO and Vo(2max). This study confirms the importance of body mass for mountain biking performance. As aerobic fitness explained only 40% of the variance, other physiological and technical factors should be investigated, as they may be important determinants of cross country performance among elite mountain bikers.

Adult↗
PubMed2005

Controversial choice of a control intervention in a trial of ventilator therapy in ARDS: standard of care arguments in a randomised controlled trial.

When evaluating an innovative intervention in a randomised controlled trial (RCT), choosing an appropriate control intervention is necessary for a clinically meaningful result. An RCT reported in 2000 addressed the relative merits of two tidal volume ventilatory strategies, 6 ml/kg (innovative) and 12 ml/kg (control), in patients with acute respiratory distress syndrome. Critics claim that the 12 ml/kg volume did not represent the clinical practice standard at that time, and that lower tidal volumes had been used in some patients prior to randomisation. The trialists responded that current practice involved the use of a broad range of tidal volumes, including 12 ml/kg. Appropriate control interventions for RCTs can be ensured by: a systematic review of the relevant literature; a formal survey of expert clinicians; and publication of the proposed research protocol to solicit critical appraisal. A global survey of experts during the RCT's design stage would have been of probative value in determining the appropriate control tidal volume. Hypothetical, but plausible, results of such a survey are presented and examined to demonstrate the value of this method.

Choice Behavior↗
PubMed2001

Is it in a neonate's best interest to enter a randomised controlled trial?

Clinicians are required to act in the best interest of neonates. However, it is not obvious that entry into a randomised controlled trial (RCT) is in a neonate's best interest because such trials often involve additional onerous procedures (such as intramuscular injections) in return for which the neonate receives unproven treatment or a placebo. On the other hand, neonatology needs to develop its evidence base, and RCTs are central to this task. The solution posited here is based on two points. First, "best interest" is not equivalent to "the best possible interest" only to "best interest within a certain realm". The realm of deliberation when asking the title question is the neonate's health. Deliberating in this realm may involve the exclusion from consideration of some factors that might be thought relevant (such as parental wealth). Furthermore, circumstances may dictate the need to deliberate on other factors that might be thought irrelevant (such as health care resources). Second, deciding on a neonate's best interest does not involve "putting oneself in its shoes". Rather, it involves asking in what it has an interest, or stake. These will include some things in which we all, as human beings, have a stake, such as medical progress. Putting these two points together, in the realm of health the answer to whether RCT entry is in a neonate's best interest is usually very finely balanced. Where this is the case, it is reasonable to invoke a broader notion of best interest and include a broader range of elements in which the neonate has a stake, including medical progress. In this way RCT entry can, usually, be said to be in a neonate's best interest.

Child Advocacy↗
PubMed2006

Exercise intensity during repeated days of racing in professional triathletes.

The purpose of this study was to estimate the exercise intensity from the competition heart rate (HR) of professional triathletes during a multi-triathlon race. Five internationally ranked professional triathletes completed incremental cycling and running tests to assess the first and second ventilatory thresholds (i.e., VT and RCT) and the HR at VT and RCT. HR was then monitored during a 5 d multi-triathlon race: a prologue time trial (PTT, 0.2 km swim -- 5 km cycle -- 1.2 km run) that opened the race; short-distance triathlons (SHD; 1.3 km swim -- 36 km cycle -- 8.4 km run) performed on the 2nd and 5th days; and sprint-distance triathlons (SPD; 0.75 km swim -- 20 km cycle -- 5 km run) performed on the 3rd and 4th days. All trials except the last (i.e., the second SHD) were performed above HR corresponding to RCT. PTT elicited significantly higher mean HR than the other trials (except for the first SPD trial). In contrast, the last SHD elicited significantly lower HR than the other trials. These responses were globally similar in the 3 segments (i.e., swim, cycle, and run). This study demonstrates that the triathletes performed at very high intensity during a drafting-permitted multi-triathlon race. However, as shown for multi-day cycling distances, the HR responses depended on (i) the distance covered and (ii) group behavior.

Adult↗
PubMed2002

Effects of amylin-related peptides on food intake, meal patterns, and gastric emptying in rats.

We previously demonstrated that amylin inhibits food intake and gastric emptying in rats with half-maximal effective doses (ED(50)s) of 8 and 3 pmol x kg(-1) x min(-1) and maximal inhibitions of 78 and 60%, respectively. In this study of identical design, rats received intravenous infusions of salmon calcitonin (sCT), rat calcitonin (rCT), rat calcitonin gene-related peptide (rCGRP), and rat adrenomedullin (rADM) for 3 h at dark onset, and food intake was measured for 17 h or for 15 min and gastric emptying of saline was measured during the final 5 min. sCT, rCGRP, and rADM inhibited food intake with estimated ED(50)s of 0.5, 26, and 35 pmol x kg(-1) x min(-1) and maximal inhibitions of 88, 90, and 49%, respectively. rCT was not effective at doses up to 100 pmol x kg(-1) x min(-1). sCT, rCGRP, rADM, and rCT inhibited gastric emptying with ED(50)s of 1, 130, 160, and 730 pmol x kg(-1) x min(-1) and maximal inhibitions of 60, 66, 60, and 33%, respectively. These results suggest that amylin and sCT may act by a common mechanism to decrease food intake, which includes inhibition of gastric emptying.

Adrenomedullin↗
PubMed1998

Pragmatic Randomised Controlled Trials for Complex Therapies.

In order to be able to 'predict' the extent or likelihood of success of an intervention, it is essential to know that exposure and effect are causally related. The randomised controlled clinical trial (RCT) is commonly referred to as the golden standard to establish causality. Apart from ethical constraints or rare diseases it is rarely impossible to do an RCT. Sometimes, however, RCTs may not be feasible (at least at first glance) due to e. g. patients' or therapists' reluctance to participate, lack of funding, organisational limitations, or because technical skills to deliver a therapy are not available. A variety of design alternatives have been proposed to overcome these problems, e. g. clinician-preferred treatment, single consent design, double consent randomised design, prerandomisation, cluster randomisation, and response-adaptive designs ('play the winner'). For complex ('combined modality') therapies it seems reasonable to study the effect of the whole treatment package on the patient rather than the value of individual components. Change to open label or optional cross-over allow 'individualized treatment' as well as 'individualized outcome' within the framework of the RCT. For clinicians and researchers it seems wise to put more emphasis on the search for a suitable and appropriate de-sign for their current problem rather than to artificially tailor their study to an awkward standard design (or even abandon the idea to seek an answer to an open question): Much more alternatives exist than one would imagine.

Journal Article↗
PubMed1997

A case report of a double-blind, randomized trial of inhaled steroids in a patient with lung transplant bronchiolitis obliterans.

Lung transplant bronchiolitis obliterans syndrome (BOS) is the most significant long-term cause of morbidity and mortality after lung transplantation. Although augmented immunosuppression is used by most centers, reported on treatment to reverse BOS are largely anecdotal. We performed a double-blind, randomized, controlled trial (RCT) with ten treatment pairs of 2 weeks duration each comparing inhaled fluticasone propionate (2 x 1,000 micrograms/day) with placebo in a patient with BOS grade 2 who previously showed an improvement in lung function after inhaled steroids. The Baseline Dyspnea Index and the Modified Medical Research Council Dyspnea Scale showed a significant improvement during fluticasone treatment compared with the placebo period (2.7 +/- 0.2 vs. 2.0 +/- 0.3; p = 0.043; and 1.7 +/- 0.2 vs. 2.4 +/- 0.2; p = 0.043). The patient correctly identified fluticasone and placebo, respectively, in eight of ten trial pairs (p = 0.016). The values of forced expiratory volume in 1 s were significantly higher during the fluticasone period (1,207 +/- 10 ml; 95% confidence interval, CI, 1,187-1,227 ml) compared to the placebo period (1,150 +/- 6 ml; 95% CI 1,138-1,162 ml; p = 0.0012). In conclusion, this n-of-1 RCT suggests the efficacy of high-dose inhaled fluticasone in our patient with lung transplant BOS. We propose to conduct a multicenter RCT of high-dose inhaled steroids. Until further data are available, this treatment modality should be offered to patients with lung transplant BOS.

Administration, Inhalation↗
PubMed2003

Effects of intravenous apolipoprotein A-I/phosphatidylcholine discs on LCAT, PLTP, and CETP in plasma and peripheral lymph in humans.

OBJECTIVE: We have previously shown that intravenous apolipoprotein A-I/phosphatidylcholine (apoA-I/PC) discs increase plasma pre-beta HDL concentration and stimulate reverse cholesterol transport (RCT) in humans. We have now investigated the associated changes in the following 3 HDL components that play key roles in RCT: lecithin:cholesterol acyltransferase (LCAT), cholesteryl ester transfer protein (CETP), and phospholipid transfer protein (PLTP). METHODS AND RESULTS: apoA-I/PC discs (40 mg/kg over 4 hours) were infused into 8 healthy men. Samples of blood and prenodal peripheral lymph were collected for 24 to 48 hours. At 12 hours, plasma LCAT concentration had increased by 0.40+/-0.90 mg/L (+7.8%; mean+/-SD; P<0.05), plasma cholesterol esterification rate by 29.0+/-9.0 nmol/mL per h (+69.5%; P<0.01), plasma CETP concentration by 0.5+/-0.2 mg/L (+29.7%; P<0.01), and plasma PLTP activity by 1.45+/-0.67 micromol/mL per h (+23.9%; P<0.01). In contrast, plasma PLTP concentration had decreased by 4.4+/-2.7 mg/L (-44.8%; P<0.01). The changes in PLTP were accompanied by alterations in the relative proportions of large lipoproteins containing inactive PLTP and small particles containing PLTP of high specific activity. No changes were detected in peripheral lymph. CONCLUSIONS: Nascent HDL secretion may induce changes in PLTP, LCAT, and CETP that promote RCT by catalyzing pre-beta HDL production, cholesterol esterification in HDLs, and cholesteryl ester transfer from HDLs to other lipoproteins.

Adult↗
PubMed2006

Cholesteryl ester transfer protein (CETP) inhibition beyond raising high-density lipoprotein cholesterol levels: pathways by which modulation of CETP activity may alter atherogenesis.

Raising high-density lipoprotein cholesterol (HDL-C) is a promising strategy in the struggle to prevent cardiovascular disease, and cholesteryl ester transfer protein (CETP) inhibitors have been developed to accomplish this. The first results are encouraging, and, in fact, in rabbits, inhibition of CETP reduces atherosclerosis. Because human data regarding the reduction of atheroma burden require more time, the biochemical mechanisms underlying the putative atheroprotection of CETP inhibitors are currently dissected, and several pathways have emerged. First, CETP inhibition increases HDL-C and reduces low-density lipoprotein cholesterol (LDL-C) levels consistent with CETP lipid transfer activity and its role in reverse cholesterol transport (RCT). This coincides with putative beneficial increases in both HDL and LDL size. However, many aspects regarding the impact of CETP inhibition on the RCT pathway remain elusive, in particular whether the first step concerning cholesterol efflux from peripheral tissues to HDL is influenced. Moreover, the relevance of scavenger receptor BI and consequently the central role of HDL in human RCT is still unclear. Second, CETP inhibition was shown recently to increase antioxidant enzymes associated with HDL, in turn associated with decreased oxidation of LDL. Atheroprotection in man is currently anticipated based on the improvement of these biochemical parameters known to influence atherosclerosis, but final confirmation regarding the impact of CETP inhibition on cardiovascular outcome will have to come from trials evaluating clinical end points.

Adipose Tissue↗
PubMed1997

Cholesteryl ester transfer protein activity enhances plasma cholesteryl ester formation. Studies in CETP transgenic mice and human genetic CETP deficiency.

The plasma cholesteryl ester transfer protein (CETP) promotes the removal of HDL cholesteryl esters and is thought to stimulate reverse cholesterol transport (RCT). However, mechanisms by which CETP may stimulate RCT are poorly understood. Thus, we examined the relationship between plasma CETP expression and plasma cholesteryl ester formation in CETP transgenic (Tg) mice, hamsters, and human subjects with genetic CETP deficiency. Incubation of CETP Tg mouse plasma showed a 20% to 40% increase in plasma cholesterol esterification rate (CER, P < .05) compared with control mice. Injection of a neutralizing CETP monoclonal antibody (MAb) (TP2) into natural flanking region CETP Tg mice resulted in an increase in plasma free cholesterol (FC) concentration, FC/CE ratio, FC/phosphatidylcholine ratio, and hepatic CETP mRNA. In hamsters, CETP inhibition also resulted in an increase in plasma FC/phosphatidylcholine ratio and increased CETP mRNA in adipose tissue. In humans with two common CETP gene mutations (an intron 14 splicing defect and a D442G missense mutation), mean plasma CERs were 39 and 60, respectively, compared with 89 nmol x mL-1 x h-1 in normal subjects. By contrast, lecithin:cholesterol acyltransferase (LCAT) mass was normal in CETP-deficient subjects. MAb neutralization of CETP activity in incubated human plasma did not alter the LCAT reaction, even after supplementation with discoidal HDL and VLDL. Thus, genetic alterations in CETP levels lead to secondary changes in the plasma LCAT reaction, possibly because of remodeling of HDL by CETP acting in concert with other factors in vivo. In human genetic CETP deficiency, a moderate impairment in the plasma LCAT reaction may contribute to a defect in RCT, providing a potential mechanism to explain the recently observed excess of coronary heart disease in these subjects.

Animals↗
PubMed2001

High density lipoproteins and arteriosclerosis. Role of cholesterol efflux and reverse cholesterol transport.

High density lipoprotein (HDL) cholesterol is an important risk factor for coronary heart disease, and HDL exerts various potentially antiatherogenic properties, including the mediation of reverse transport of cholesterol from cells of the arterial wall to the liver and steroidogenic organs. Enhancement of cholesterol efflux and of reverse cholesterol transport (RCT) is considered an important target for antiatherosclerotic drug therapy. Levels and composition of HDL subclasses in plasma are regulated by many factors, including apolipoproteins, lipolytic enzymes, lipid transfer proteins, receptors, and cellular transporters. In vitro experiments as well as genetic family and population studies and investigation of transgenic animal models have revealed that HDL cholesterol plasma levels do not necessarily reflect the efficacy and antiatherogenicity of RCT. Instead, the concentration of HDL subclasses, the mobilization of cellular lipids for efflux, and the kinetics of HDL metabolism are important determinants of RCT and the risk of atherosclerosis.

Animals↗
PubMed2003

Validity of a simple ST-elevation acute myocardial infarction risk index: are randomized trial prognostic estimates generalizable to elderly patients?

BACKGROUND: Risk-stratification scores derived from randomized clinical trial (RCT) data should be evaluated in community-based populations. A simple risk-stratification index for patients with ST-segment elevation myocardial infarction derived from an RCT population was recently proposed, but it has not been validated in a community-based cohort. METHODS AND RESULTS: We evaluated the simple risk index using data from 49 711 patients > or =65 years of age hospitalized with ST-elevation myocardial infarction. We evaluated the distribution of patients in the 5 simple risk index groups, compared observed and published 30-day mortality rates, and assessed the score's discrimination and calibration. The simple risk index provided poor discrimination (c=0.62) and calibration (goodness of fit P<0.001) for survival at 30 days. Risk score distribution was skewed, because two thirds (66.1%) of all patients were classified in the highest-risk group, whereas fewer than 11.0% were classified in the 3 lowest-risk groups. Thirty-day mortality estimates were lower than those observed in the cohort (risk group 2 to 5: 1.9% to 17.4% versus 5.3% to 27.9%). Risk index discrimination, calibration, score distribution, and mortality estimates were worse among patients who did not receive acute reperfusion therapy than among those who did. CONCLUSIONS: The limited performance of the simple risk index highlights the limitations of applying prognostic models derived in RCT populations to the general population of patients 65 years and older. Prognostic scores must be validated in community-based cohorts before integration into clinical practice.

Aged↗
PubMed2005

Pharmacological activation of liver X receptors promotes reverse cholesterol transport in vivo.

BACKGROUND: Liver X receptors (LXRs) are ligand-activated transcription factors involved in the control of lipid metabolism and inflammation. Synthetic LXR agonists have been shown to inhibit the progression of atherosclerosis in mice, but the mechanism is uncertain. LXR agonism upregulates the genes encoding ATP binding cassette transporters A1 (ABCA1) and G1 (ABCG1) in macrophages, thus promoting efflux of cholesterol; it also upregulates liver and intestinal ABCG5 and ABCG8, helping to promote biliary and fecal excretion of cholesterol. Thus, LXR agonism may inhibit atherosclerosis through promotion of reverse cholesterol transport (RCT) in vivo, but this has not been proven. We previously described an in vivo method to trace the movement of cholesterol from 3H-cholesterol-labeled J774 macrophages into plasma, into liver, and ultimately into the bile and feces as free cholesterol or bile acids. In the present study we used this approach to test the hypothesis that administration of the synthetic LXR agonist GW3965 would increase the rate of macrophage RCT in vivo. METHODS AND RESULTS: Three different mouse models-wild-type C57BL/6 mice, LDLR/apobec-1 double knockout mice, and human apolipoprotein (apo)B/cholesteryl ester transfer protein (CETP) double transgenic mice-were treated with either vehicle or GW3965. Mice were injected intraperitoneally with 3H-cholesterol-labeled and cholesterol-loaded macrophages and monitored for the appearance of 3H-tracer in plasma, liver, and feces. Administration of GW3965 significantly increased the levels of 3H-tracer in plasma and feces in all 3 mouse models. CONCLUSIONS: These results demonstrate that administration of the LXR agonist GW3965 increases the rate of RCT from macrophages to feces in vivo.

APOBEC-1 Deaminase↗
PubMed1999

Coughing in laryngectomized patients.

Ablation of the larynx implies withdrawal of afferent information from receptors involved both in the control of expiratory flow and in the genesis of protective airway reflexes including coughing. To investigate the effects of laryngectomy on the sensory and motor component of coughing, maximal voluntary cough (MVC) efforts as well as the reflex cough (RC) responses at threshold (T) and suprathreshold (1.8 x T, ST) levels induced by inhalation of progressively increasing concentrations of ultrasonically nebulized distilled water (fog) were analyzed in 10 laryngectomized patients and 10 control subjects. Cough intensity was indexed in terms of both the peak amplitude of the integrated electromyographic activity of abdominal muscles (IEMGP) and the ratio of IEMGP to the duration of the expiratory ramp (TEC), i.e., the rate of rise of IEMG activity (IEMGP/TEC). Cough peak flow was also recorded. Cough threshold was similar in patients and controls, as were IEMGP, TEC, and IEMGP/ TEC recorded during MVC and RCST. In contrast, during RCT, patients' IEMGP was significantly reduced (p < 0.05), thus leading to a significant decrease in IEMGP/TEC (p < 0.05) even in the absence of significant differences in TEC. Cough flow closely correlated with IEMG-related variables. Cough volume acceleration, i. e., the ratio of cough peak flow to the corresponding time to cough peak flow was also significantly reduced in the patients, especially during RCT (p < 0.01). The results suggest that the lack of signals arising from the larynx may result in a reduction of cough volume acceleration as well as in the intensity of abdominal muscle contractions during RCT. These factors may contribute to facilitate the onset and/or the persistence of chest infections in laryngectomized patients.

Abdominal Muscles↗
PubMed2005

Hepatic expression of scavenger receptor class B type I (SR-BI) is a positive regulator of macrophage reverse cholesterol transport in vivo.

Hepatic expression of the scavenger receptor class B type I (SR-BI) promotes selective uptake of HDL cholesterol by the liver and is believed to play a role in the process of reverse cholesterol transport (RCT). We hypothesized that hepatic SR-BI expression is a regulator of the rate of integrated macrophage-to-feces RCT and used an in vivo model to test this hypothesis. Cholesterol-loaded and [3H]cholesterol-labeled J774 macrophages were injected intraperitoneally into mice, after which the appearance of the [3H]cholesterol in the plasma, liver, and feces over 48 hours was quantitated. Mice overexpressing SR-BI in the liver had significantly reduced [3H]cholesterol in the plasma but markedly increased [3H] tracer excretion in the feces over 48 hours. Conversely, mice deficient in SR-BI had significantly increased [3H]cholesterol in the plasma but markedly reduced [3H] tracer excretion in the feces over 48 hours. These studies demonstrate that hepatic SR-BI expression, despite its inverse effects on steady-state plasma HDL cholesterol concentrations, is an important positive regulator of the rate of macrophage RCT.

Animals↗
PubMed1998

A systematic review of compression therapy for venous leg ulcers.

The aim of the study was to determine the relative effectiveness of compression therapies used in the treatment of venous leg ulcers. Randomized controlled trials (RCT) were sought using a search strategy that aimed to identify relevant RCT by searching eight electronic databases (including Medline, Embase and CINHAL), conference proceedings and hand searching key journals. In addition, citations within papers were scrutinized to identify any relevant studies. Suitability for inclusion in this review was determined by a critical appraisal of key determinants of the quality of the trials. Trials that included patients of mixed ulcer aetiology were excluded unless the results of patients with venous disease were reported separately. Data was extracted independently by two reviewers and synthesized quantitatively and qualitatively. Losses to follow-up/withdrawals were assumed to be failures of treatment. A total of 132 articles were identified, and of these eight fulfilled the inclusion criteria. The remaining 126 trials were excluded due to trial design flaws, the inclusion of mixed/arterial aetiology ulcers or because they were non-RCT. Meta-analysis using a random-effects model showed the benefits of multi-layer and elastic compression bandages. It was concluded that more high-quality trials are required and that more emphasis should be placed on economic and quality of life data to try to ascertain the cost-effectiveness and utility of the treatment options available.

Bandages↗
PubMed2001

The CONSORT statement: revised recommendations for improving the quality of reports of parallel group randomized trials.

To comprehend the results of a randomized controlled trial (RCT), readers must understand its design, conduct, analysis and interpretation. That goal can only be achieved through complete transparency from authors. Despite several decades of educational efforts, the reporting of RCTs needs improvement. Investigators and editors developed the original CONSORT (Consolidated Standards of Reporting Trials) statement to help authors improve reporting by using a checklist and flow diagram. The revised CONSORT statement presented in this paper incorporates new evidence and addresses some criticisms of the original statement.The checklist items pertain to the content of the Title, Abstract, Introduction, Methods, Results and Discussion. The revised checklist includes 22-items selected because empirical evidence indicates that not reporting the information is associated with biasedestimates of treatment effect or the information is essential to judge the reliability or relevance of the findings. We intended the flow diagram to depict the passage of participants through an RCT. The revised flow diagram depicts information from four stages of a trial (enrollment, intervention allocation, follow-up, and analysis). The diagram explicitly includes the number of participants, for each intervention group, included in the primary data analysis. Inclusion of these numbers allows the reader to judge whether the authors have performed an intention-to-treat analysis.In sum, the CONSORT statement is intended to improve the reporting of an RCT, enabling readers to understand a trial's conduct and to assess the validity of its results.

Humans↗
PubMed2005

A simplified search strategy for identifying randomised controlled trials for systematic reviews of health care interventions: a comparison with more exhaustive strategies.

BACKGROUND: It is generally believed that exhaustive searches of bibliographic databases are needed for systematic reviews of health care interventions. The CENTRAL database of controlled trials (RCTs) has been built up by exhaustive searching. The CONSORT statement aims to encourage better reporting, and hence indexing, of RCTs. Our aim was to assess whether developments in the CENTRAL database, and the CONSORT statement, mean that a simplified RCT search strategy for identifying RCTs now suffices for systematic reviews of health care interventions. METHODS: RCTs used in the Cochrane reviews were identified. A brief RCT search strategy (BRSS), consisting of a search of CENTRAL, and then for variants of the word random across all fields (random$.af.) in MEDLINE and EMBASE, was devised and run. Any trials included in the meta-analyses, but missed by the BRSS, were identified. The meta-analyses were then re-run, with and without the missed RCTs, and the differences quantified. The proportion of trials with variants of the word random in the title or abstract was calculated for each year. The number of RCTs retrieved by searching with "random$.af." was compared to the highly sensitive search strategy (HSSS). RESULTS: The BRSS had a sensitivity of 94%. It found all journal RCTs in 47 of the 57 reviews. The missing RCTs made some significant differences to a small proportion of the total outcomes in only five reviews, but no important differences in conclusions resulted. In the post-CONSORT years, 1997-2003, the percentage of RCTs with random in the title or abstract was 85%, a mean increase of 17% compared to the seven years pre-CONSORT (95% CI, 8.3% to 25.9%). The search using random$.af. reduced the MEDLINE retrieval by 84%, compared to the HSSS, thereby reducing the workload of checking retrievals. CONCLUSION: A brief RCT search strategy is now sufficient to locate RCTs for systematic reviews in most cases. Exhaustive searching is no longer cost-effective, because in effect it has already been done for CENTRAL.

Abstracting and Indexing↗