188 resultados para cluster randomised control trial
Resumo:
Background
Learning to read is a key goal during primary school: reading difficulties may curtail children’s learning trajectories. Controversy remains regarding what types of interventions are effective for children at risk for academic failure, such as children in disadvantaged areas. We present data from a complex intervention to test the hypothesis that phonic skills and word recognition abilities are a pivotal and specific causal mechanism for the development of reading skills in children at risk for poorer literacy outcomes.
Method
Over 500 pupils across 16 primary schools took part in a Cluster Randomised Controlled Trial from school year 1 to year 3. Schools were randomly allocated to the intervention or the control arm. The intervention involved a literacy-rich after-school programme. Children attending schools in the control arm of the study received the curriculum normally provided. Children in both arms completed batteries of language, phonic skills, and reading tests every year. We used multilevel mediation models to investigate mediating processes between intervention and outcomes.
Findings
Children who took part in the intervention displayed improvements in reading skills compared to those in the control arm. Results indicated a significant indirect effect of the intervention via phonics encoding.
Discussion
The results suggest that the intervention was effective in improving reading abilities of children at risk, and this effect was mediated by improving children’s phonic skills. This has relevance for designing interventions aimed at improving literacy skills of children exposed to socio-economic disadvantage. Results also highlight the importance of methods to investigate causal pathways from intervention to outcomes.
Resumo:
Background and aims
Public health campaigns recommend increased fruit and vegetable (FV) consumption as an effective means of cardiovascular risk reduction. During an 8 week randomised control trial among hypertensive volunteers, we noted significant improvements in endothelium-dependent vasodilatation with increasing FV consumption. Circulating indices of inflammation, endothelial activation and insulin resistance are often employed as alternative surrogates for systemic arterial health. The responses of several such biomarkers to our previously described FV intervention are reported here.
Methods and results
Hypertensive volunteers were recruited from medical outpatient clinics. After a common 4 week run-in period during which FV consumption was limited to 1 portion per day, participants were randomised to 1, 3 or 6 portions daily for 8 weeks. Venous blood samples for biomarker analyses were collected during the pre and post-intervention vascular assessments. A total of 117 volunteers completed the 12 week study. Intervention-related changes in circulating levels of high sensitivity C-reactive protein (hsCRP), soluble intracellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), von Willebrand factor (vWF) and plasminogen activator inhibitor-1 (PAI-1) did not differ significantly between FV groups. Similarly, there were no significant between group differences of change in homeostasis model assessment (HOMA) scores.
Conclusions
Despite mediating a significant improvement in acetylcholine induced vasodilatation, increased FV consumption did not affect a calculated measure of insulin resistance or concentrations of the circulating biomarkers measured during this study. Functional indices of arterial health such as endothelium-dependent vasomotion are likely to provide more informative cardiovascular end-points during short-term dietary intervention trials.
Resumo:
Topic Background: Peace education initiatives in schools are often based on social psychological theories assuming that social identity affects ingroup and outgroup attitudes and, in turn, behaviors relating to relevant outgroups. However, research evidence on the role of children's social identity has often failed to take account of different social identity dimensions or to conceptualise behavior in the context of children's understandings of the social world. While recent research relating to bullying and bystander behavior amongst children has addressed the latter point, this has rarely been considered in conjunction with a differentiated view of social identity. This paper is therefore distinctive as it will address the role of social identity dimensions with regards to reported behavior as captured in bystander scenarios relating to outgroup derogation. This is particularly important in the context of divided societies, where peace education initiatives are crucial in promoting positive community relations for the future and where such initiative may be hampered by communities' concerns about loss of identity. In the context of Northern Ireland, a divided society emerging from conflict, social identity, outgroup attitudes and behaviours have been key concepts addressed by peace educators
for many years.
Research questions: This paper therefore set out to investigate the relationship between social identity, measured as affiliation with the group and exploration of its meaning for the child, sectarian attitudes and pupils' reported willingness to challenge sectarian bullying in their school environment in Northern Ireland.
Research methods: The findings are based on the analysis of a baseline survey, which forms part of a randomised control trial of an intervention aimed at promoting community relations and reconciliation. The trial includes 35 primary and post-primary schools and about 800 pupils from 8-11 years old who completed an online questionnaire at the start of the programme. Main instruments for this study included adapted scales measuring identity affiliation and identity exploration, sectarian attitudes and scenarios capturing pupils' intentions in bystander situations relating to sectarian bullying.
Analytical framework: Results are analysed using regression analysis and additionally investigate gender and religious differences.
Research findings and/or contribution to knowledge: Results are discussed in the light of the role of social identity dimensions and their relationship to outgroup attitudes and willingness to challenge outgroup derogation. The paper concludes with potential implications for peace education initiatives in Northern Ireland and beyond.
Resumo:
Background: Potentially inappropriate prescribing (PIP) in older people is common in primary care and can result in increased morbidity, adverse drug events, hospitalizations and mortality. The prevalence of PIP in Ireland is estimated at 36% with an associated expenditure of over [euro sign]45 million in 2007. The aim of this paper is to describe the application of the Medical Research Council (MRC) framework to the development of an intervention to decrease PIP in Irish primary care.
Methods: The MRC framework for the design and evaluation of complex interventions guided the development of the study intervention. In the development stage, literature was reviewed and combined with information obtained from experts in the field using a consensus based methodology and patient cases to define the main components of the intervention. In the pilot stage, five GPs tested the proposed intervention. Qualitative interviews were conducted with the GPs to inform the development and implementation of the intervention for the main randomised controlled trial.
Results: The literature review identified PIP criteria for inclusion in the study and two initial intervention components - academic detailing and medicines review supported by therapeutic treatment algorithms. Through patient case studies and a focus group with a group of 8 GPs, these components were refined and a third component of the intervention identified - patient information leaflets. The intervention was tested in a pilot study. In total, eight medicine reviews were conducted across five GP practices. These reviews addressed ten instances of PIP, nine of which were addressed in the form of either a dose reduction or a discontinuation of a targeted medication. Qualitative interviews highlighted that GPs were receptive to the intervention but patient preference and time needed both to prepare for and conduct the medicines review, emerged as potential barriers. Findings from the pilot study allowed further refinement to produce the finalised intervention of academic detailing with a pharmacist, medicines review with web-based therapeutic treatment algorithms and tailored patient information leaflets.
Conclusions: The MRC framework was used in the development of the OPTI-SCRIPT intervention to decrease the level of PIP in primary care in Ireland. Its application ensured that the intervention was developed using the best available evidence, was acceptable to GPs and feasible to deliver in the clinical setting. The effectiveness of this intervention is currently being tested in a pragmatic cluster randomised controlled trial.
Trial registration: Current controlled trials ISRCTN41694007.© 2013 Clyne et al.; licensee BioMed Central Ltd.
Resumo:
To determine if calcium scores (CS) could act as a more effective gatekeeper than Diamond Forrester (DF) in the assessment of patients with suspected coronary artery disease (CAD). A sub-study of the Cardiac CT for the Assessment of Chest Pain and Plaque (CAPP) study, a randomised control trial evaluating the cost-effectiveness of cardiac CT in symptomatic patients with stable chest pain. Stable pain was defined as troponin negative pain without symptoms of unstable angina. 250 patients undergoing cardiac CT had both DF scores and CS calculated, with the accuracy of both evaluated against CT coronary angiogram. Criteria given in UK national guidelines were compared. Of the 250 patients, 4 withdrew. 140 (57 %) patients were male. The mean DF was 47.8 and mean CS 172.5. Of the 144 patients with non-anginal pain 19.4 % had significant disease (>50 % stenosis). In general the DF over estimated the presence of CAD whereas the CS reclassified patients to lower risk groups, with 91 in the high risk DF category compared to 26 in the CS. Both receiver operating curve and McNemar Bowker test analysis suggested the DF was less accurate in the prediction of CAD compared to CS [Formula: see text] Projected downstream investigations were also calculated, with the cost per number of significant stenoses identified cheaper with the CS criteria. Patients with suspected stable CAD are more accurately risk stratified by CS compared to the traditional DF. CS was more successful in the prediction of significant stenosis and appears to be more effective at targeting clinical resources to those patients that are in need of them.
Resumo:
Purpose
The Strengths and Difficulties Questionnaire (SDQ) is a behavioural screening tool for children. The SDQ is increasingly used as the primary outcome measure in population health interventions involving children, but it is not preference based; therefore, its role in allocative economic evaluation is limited. The Child Health Utility 9D (CHU9D) is a generic preference-based health-related quality of-life measure. This study investigates the applicability of the SDQ outcome measure for use in economic evaluations and examines its relationship with the CHU9D by testing previously published mapping algorithms. The aim of the paper is to explore the feasibility of using the SDQ within economic evaluations of school-based population health interventions.
Methods
Data were available from children participating in a cluster randomised controlled trial of the school-based roots of empathy programme in Northern Ireland. Utility was calculated using the original and alternative CHU9D tariffs along with two SDQ mapping algorithms. t tests were performed for pairwise differences in utility values from the preference-based tariffs and mapping algorithms.
Results
Mean (standard deviation) SDQ total difficulties and prosocial scores were 12 (3.2) and 8.3 (2.1). Utility values obtained from the original tariff, alternative tariff, and mapping algorithms using five and three SDQ subscales were 0.84 (0.11), 0.80 (0.13), 0.84 (0.05), and 0.83 (0.04), respectively. Each method for calculating utility produced statistically significantly different values except the original tariff and five SDQ subscale algorithm.
Conclusion
Initial evidence suggests the SDQ and CHU9D are related in some of their measurement properties. The mapping algorithm using five SDQ subscales was found to be optimal in predicting mean child health utility. Future research valuing changes in the SDQ scores would contribute to this research.
Resumo:
OBJECTIVES. Adherence to hand hygiene among healthcare workers (HCWs) is widely believed to be a key factor in reducing the spread of healthcare-associated infection. The objective of this study was to evaluate the impact of a multifaceted intervention to increase rates of adherence to hand hygiene among HCWs and to assess the effect on the incidence of hospital-acquired methicillin-resistant Staphylococcus aureus (MRSA) colonization. DESIGN. Cluster-randomized controlled trial. SETTING. Thirty hospital units in 3 tertiary care hospitals in Hamilton, Ontario, Canada. INTERVENTION. After a 3-month baseline period of data collection, 15 units were randomly assigned to the intervention arm (with performance feedback, small-group teaching seminars, and posters) and 15 units to usual practice. Hand hygiene was observed during randomly selected 15-minute periods on each unit, and the incidence of MRSA colonization was measured using weekly surveillance specimens from June 2007 through May 2008. RESULTS. We found that 3,812 (48.2%) of 7,901 opportunities for hand hygiene in the intervention group resulted in adherence, compared with 3,205 (42.6%) of 7,526 opportunities in the control group (P <.001; independent t test). There was no reduction in the incidence of hospital-acquired MRSA colonization in the intervention group. CONCLUSION. Among HCWs in Ontario tertiary care hospitals, the rate of adherence to hand hygiene had a statistically significant increase of 6% with a multifaceted intervention, but the incidence of MRSA colonization was not reduced.
Resumo:
Background
Results of several trials of antioxidant use during pregnancy have not shown a reduction in pre-eclampsia, but the eff ect in women with diabetes is unknown. We aimed to assess whether supplementation with vitamins C and E reduced incidence of pre-eclampsia in women with type 1 diabetes.
Methods
We enrolled women from 25 UK antenatal metabolic clinics in a multicentre randomised placebo-controlled trial. Eligibility criteria were type 1 diabetes preceding pregnancy, presentation between 8 weeks’ and 22 weeks’ gestation, singleton pregnancy, and age 16 years or older. Women were randomly allocated in a 1:1 ratio to receive1000 mg vitamin C and 400 IU vitamin E (a-tocopherol) or matched placebo daily until delivery. The randomisation sequence was stratifi ed by centre with balanced blocks of eight patients. All trial personnel and participants were masked to treatment allocation. The primary endpoint was pre-eclampsia, which we defi ned as gestational hypertension with proteinuria. Analysis was by modifi ed intention to treat. This study is registered, ISRCTN27214045.
Findings
Between April, 2003, and June, 2008, 762 women were randomly allocated to treatment groups (379 vitamin supplementation, 383 placebo). The primary endpoint was assessed for 375 women allocated to receive vitamins, and 374 allocated to placebo. Rates of pre-eclampsia did not differ between vitamin (15%, n=57) and placebo (19%, 70)groups (risk ratio 0·81, 95% CI 0·59–1·12). No adverse maternal or neonatal outcomes were reported.
Interpretation
Supplementation with vitamins C and E did not reduce risk of pre-eclampsia in women with type 1 diabetes. However, the possibility that vitamin supplementation might be benefi cial in women with a low antioxidant status at baseline needs further testing.
Resumo:
Background: In the Medical Research Council (MRC) COIN trial, the epidermal growth factor receptor (EGFR)-targeted antibody cetuximab was added to standard chemotherapy in first-line treatment of advanced colorectal cancer with the aim of assessing effect on overall survival.
Methods: In this randomised controlled trial, patients who were fit for but had not received previous chemotherapy for advanced colorectal cancer were randomly assigned to oxaliplatin and fluoropyrimidine chemotherapy (arm A), the same combination plus cetuximab (arm B), or intermittent chemotherapy (arm C). The choice of fluoropyrimidine therapy (capecitabine or infused fluouroracil plus leucovorin) was decided before randomisation. Randomisation was done centrally (via telephone) by the MRC Clinical Trials Unit using minimisation. Treatment allocation was not masked. The comparison of arms A and C is described in a companion paper. Here, we present the comparison of arm A and B, for which the primary outcome was overall survival in patients with KRAS wild-type tumours. Analysis was by intention to treat. Further analyses with respect to NRAS, BRAF, and EGFR status were done. The trial is registered, ISRCTN27286448.
Findings: 1630 patients were randomly assigned to treatment groups (815 to standard therapy and 815 to addition of cetuximab). Tumour samples from 1316 (81%) patients were used for somatic molecular analyses; 565 (43%) had KRAS mutations. In patients with KRAS wild-type tumours (arm A, n=367; arm B, n=362), overall survival did not differ between treatment groups (median survival 17·9 months [IQR 10·3—29·2] in the control group vs 17·0 months [9·4—30·1] in the cetuximab group; HR 1·04, 95% CI 0·87—1·23, p=0·67). Similarly, there was no effect on progression-free survival (8·6 months [IQR 5·0—12·5] in the control group vs 8·6 months [5·1—13·8] in the cetuximab group; HR 0·96, 0·82—1·12, p=0·60). Overall response rate increased from 57% (n=209) with chemotherapy alone to 64% (n=232) with addition of cetuximab (p=0·049). Grade 3 and higher skin and gastrointestinal toxic effects were increased with cetuximab (14 vs 114 and 67 vs 97 patients in the control group vs the cetuximab group with KRAS wild-type tumours, respectively). Overall survival differs by somatic mutation status irrespective of treatment received: BRAF mutant, 8·8 months (IQR 4·5—27·4); KRAS mutant, 14·4 months (8·5—24·0); all wild-type, 20·1 months (11·5—31·7).
Interpretation: This trial has not confirmed a benefit of addition of cetuximab to oxaliplatin-based chemotherapy in first-line treatment of patients with advanced colorectal cancer. Cetuximab increases response rate, with no evidence of benefit in progression-free or overall survival in KRAS wild-type patients or even in patients selected by additional mutational analysis of their tumours. The use of cetuximab in combination with oxaliplatin and capecitabine in first-line chemotherapy in patients with widespread metastases cannot be recommended.
Resumo:
Background: When cure is impossible, cancer treatment should focus on both length and quality of life. Maximisation of time without toxic effects could be one effective strategy to achieve both of these goals. The COIN trial assessed preplanned treatment holidays in advanced colorectal cancer to achieve this aim. Methods: COIN was a randomised controlled trial in patients with previously untreated advanced colorectal cancer. Patients received either continuous oxaliplatin and fluoropyrimidine combination (arm A), continuous chemotherapy plus cetuximab (arm B), or intermittent (arm C) chemotherapy. In arms A and B, treatment continued until development of progressive disease, cumulative toxic effects, or the patient chose to stop. In arm C, patients who had not progressed at their 12-week scan started a chemotherapy-free interval until evidence of disease progression, when the same treatment was restarted. Randomisation was done centrally (via telephone) by the MRC Clinical Trials Unit using minimisation. Treatment allocation was not masked. The comparison of arms A and B is described in a companion paper. Here, we compare arms A and C, with the primary objective of establishing whether overall survival on intermittent therapy was non-inferior to that on continuous therapy, with a predefined non-inferiority boundary of 1·162. Intention-to-treat (ITT) and per-protocol analyses were done. This trial is registered, ISRCTN27286448. Findings: 1630 patients were randomly assigned to treatment groups (815 to continuous and 815 to intermittent therapy). Median survival in the ITT population (n=815 in both groups) was 15·8 months (IQR 9·4—26·1) in arm A and 14·4 months (8·0—24·7) in arm C (hazard ratio [HR] 1·084, 80% CI 1·008—1·165). In the per-protocol population (arm A, n=467; arm C, n=511), median survival was 19·6 months (13·0—28·1) in arm A and 18·0 months (12·1—29·3) in arm C (HR 1·087, 0·986—1·198). The upper limits of CIs for HRs in both analyses were greater than the predefined non-inferiority boundary. Preplanned subgroup analyses in the per-protocol population showed that a raised baseline platelet count, defined as 400 000 per µL or higher (271 [28%] of 978 patients), was associated with poor survival with intermittent chemotherapy: the HR for comparison of arm C and arm A in patients with a normal platelet count was 0·96 (95% CI 0·80—1·15, p=0·66), versus 1·54 (1·17—2·03, p=0·0018) in patients with a raised platelet count (p=0·0027 for interaction). In the per-protocol population, more patients on continuous than on intermittent treatment had grade 3 or worse haematological toxic effects (72 [15%] vs 60 [12%]), whereas nausea and vomiting were more common on intermittent treatment (11 [2%] vs 43 [8%]). Grade 3 or worse peripheral neuropathy (126 [27%] vs 25 [5%]) and hand—foot syndrome (21 [4%] vs 15 [3%]) were more frequent on continuous than on intermittent treatment. Interpretation: Although this trial did not show non-inferiority of intermittent compared with continuous chemotherapy for advanced colorectal cancer in terms of overall survival, chemotherapy-free intervals remain a treatment option for some patients with advanced colorectal cancer, offering reduced time on chemotherapy, reduced cumulative toxic effects, and improved quality of life. Subgroup analyses suggest that patients with normal baseline platelet counts could gain the benefits of intermittent chemotherapy without detriment in survival, whereas those with raised baseline platelet counts have impaired survival and quality of life with intermittent chemotherapy and should not receive a treatment break.
Resumo:
Background: There is a need to improve the effectiveness of strategies to help cardiac rehabilitation patients achieve recommended levels of physical activity; the use of pedometers requires further research. We aimed to examine the feasibility of a randomised controlled trial, of an intervention using pedometer step-count goals, to promote physical activity for cardiac rehabilitation patients. Methods: We invited patients who completed a supervised cardiac rehabilitation programme to participate in this community-based study. Consenting participants wore a Yamax CW-701 pedometer for one week, blinded to stepcount readings, before being randomly allocated to groups. Intervention groups were told their step-counts; working with a clinical facilitator (nurse or physiotherapist) individually, they set daily step-count goals and reviewed these weekly. Baseline step-counts were hidden from controls, who were not given pedometers but received ongoing weekly facilitator support. After six weeks both groups wore ‘blinded’ pedometers for outcome assessment and participated in semi-structured interviews which explored their experiences of the study. Outcomes included rates of uptake, adherence and completion of measures, including step-counts, quality of life (EQ-5D) and stage of behaviour change. Results: Four programme groups were recruited; two received the intervention. Of 68 invitees, 45 participated (66%) (19 intervention; 26 control). Forty-two (93%) completed the outcomes. Baseline characteristics were comparable between groups. Mean steps/day increased more for intervention participants (2,742; 95%CI 1,169 to 4,315) than controls (-42; 95%CI -1,102 to 1,017) (p=0.004). The intervention and on-going clinical contact were welcomed; participants considered that step-counts, compared to time-related targets, encouraged them to become more active. Conclusion: These findings suggest that an intervention using individually tailored step-count goals may help increase and sustain physical activity following a cardiac rehabilitation programme. A definitive randomised controlled trial using blinded outcome measurements is feasible and of potential value in determining how best to translate physical activity advice into practice.
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Acute lung injury is a common, devastating clinical syndrome associated with substantial mortality and morbidity with currently no proven therapeutic interventional strategy to improve patient outcomes. The objectives of this study are to test the potential therapeutic effects of keratinocyte growth factor for patients with acute lung injury on oxygenation and biological indicators of acute inflammation, lung epithelial and endothelial function, protease:antiprotease balance, and lung extracellular matrix degradation and turnover.
Resumo:
Aromatase inhibitors effectively prevent breast cancer recurrence and development of new contralateral tumours in postmenopausal women. We assessed the efficacy and safety of the aromatase inhibitor anastrozole for prevention of breast cancer in postmenopausal women who are at high risk of the disease.