A review of methodology for sample size calculations in cluster randomised trials

PMCID: PMC3287737This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.PMCID: PMC3287737PMCID: PMC3287737PMCID: PMC3287737PMCID: PMC3287737PMCID: PMC3287737PMCID: PMC328773

Primary care Identification and Referral to Improve Safety of women experiencing domestic violence (IRIS): protocol for a pragmatic cluster randomised controlled trial

BACKGROUND: Domestic violence, which may be psychological, physical, sexual, financial or emotional, is a major public health problem due to the long-term health consequences for women who have experienced it and for their children who witness it. In populations of women attending general practice, the prevalence of physical or sexual abuse in the past year from a partner or ex-partner ranges from 6 to 23%, and lifetime prevalence from 21 to 55%. Domestic violence is particularly important in general practice because women have many contacts with primary care clinicians and because women experiencing abuse identify doctors and nurses as professionals from whom they would like to get support. Yet health professionals rarely ask about domestic violence and have little or no training in how to respond to disclosure of abuse. METHODS/DESIGN: This protocol describes IRIS, a pragmatic cluster randomised controlled trial with the general practice as unit of randomisation. Our trial tests the effectiveness and cost-effectiveness of a training and support programme targeted at general practice teams. The primary outcome is referral of women to specialist domestic violence agencies. Forty-eight practices in two UK cities (Bristol and London) are randomly allocated, using minimisation, into intervention and control groups. The intervention, based on an adult learning model in an educational outreach framework, has been designed to address barriers to asking women about domestic violence and to encourage appropriate responses to disclosure and referral to specialist domestic violence agencies. Multidisciplinary training sessions are held with clinicians and administrative staff in each of the intervention practices, with periodic feedback of identification and referral data to practice teams. Intervention practices have a prompt to ask about abuse integrated in the electronic medical record system. Other components of the intervention include an IRIS champion in each practice and a direct referral pathway to a named domestic violence advocate. DISCUSSION: This is the first European randomised controlled trial of an intervention to improve the health care response to domestic violence. The findings will have the potential to inform training and service provision. TRIAL REGISTRATION: ISRCTN74012786

Effectiveness of structured patient-clinician communication with a solution focused approach (DIALOG+) in community treatment of patients with psychosis - a cluster randomised controlled trial

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

Survival of Civilian and Prisoner Drug-Sensitive, Multi- and Extensive Drug- Resistant Tuberculosis Cohorts Prospectively Followed in Russia

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Microbicides Development Programme: design of a phase III trial to measure the efficacy of the vaginal microbicide PRO 2000/5 for HIV prevention.

BACKGROUND: With 2.5 million new HIV infections per year, effective preventive methods against HIV are urgently needed, especially in sub-Saharan Africa. MDP301 is an ongoing trial of the vaginal microbicide PRO 2000/5 being conducted by the Microbicides Development Programme. The main objective of the trial is to determine the efficacy and safety of 0.5% and 2% concentrations of PRO 2000/5 gel compared to placebo in preventing vaginally acquired HIV infection. METHODS/DESIGN: MDP301 is a multicentre randomised placebo-controlled Phase III trial. The design was informed by pre-trial feasibility and pilot studies. The choice of trial population, assessments and endpoints are discussed along with statistical and ethical considerations. Adaptations to the design were made during the conduct of the trial; these included closing a study arm and changing the timing of the primary endpoint. DISCUSSION: The development of effective microbicide products remains one of the strongest hopes for new biomedical prevention tools. MDP301 is the largest Phase III microbicide trial to date, with 9404 enrolments, and is scheduled for completion in September 2009. Results are expected towards the end of 2009

Study Protocol for a randomized controlled trial of mentalization based therapy against specialist supportive clinical management in patients with both eating disorders and symptoms of borderline personality disorder

The NOURISHED study: Nice OUtcomes for Referrals with Impulsivity, Self Harm and Eating Disorders.Eating Disorders (ED) and Borderline Personality Disorder (BPD) are both difficult to treat and the combination presents particular challenges. Both are associated with vulnerability to loss of mentalization (awareness of one's own and others' emotional state) In BPD, Mentalization Based therapy (MBT) has been found effective in reducing symptoms. In this trial we investigate the effectiveness and cost-effectiveness of MBT adapted for Eating disorders (Mentalization Based Therapy for Eating Disorders (MBT-ED))compared to a standard comparison treatment, Specialist Supportive Clinical Management SSCM-ED) in patients with a combination of an Eating Disorder and either a diagnosis of BPD or a history of self-harm and impulsivity in the previous 12 months

Prenatal alcohol exposure and childhood atopic disease:A Mendelian randomization approach

BACKGROUND: Alcohol consumption in western pregnant women is not uncommon and could be a risk factor for childhood atopic disease. However, reported alcohol intake may be unreliable, and associations are likely to be confounded. OBJECTIVE: We aimed to study the relation between prenatal alcohol exposure and atopic phenotypes in a large population-based birth cohort with the use of a Mendelian randomization approach to minimize bias and confounding. METHODS: In white mothers and children in the Avon Longitudinal Study of Parents and Children (ALSPAC) we first analyzed associations between reported maternal alcohol consumption during pregnancy and atopic outcomes in the offspring measured at 7 years of age (asthma, wheezing, hay fever, eczema, atopy, and total IgE). We then analyzed the relation of maternal alcohol dehydrogenase (ADH)1B genotype (rs1229984) with these outcomes (the A allele is associated with faster metabolism and reduced alcohol consumption and, among drinkers, would be expected to reduce fetal exposure to ethanol). RESULTS: After controlling for confounders, reported maternal drinking in late pregnancy was negatively associated with childhood asthma and hay fever (adjusted odds ratio [OR] per category increase in intake: 0.91 [95% CI, 0.82-1.01] and 0.87 [95% CI, 0.78-0.98], respectively). However, maternal ADH1B genotype was not associated with asthma comparing carriers of A allele with persons homozygous for G allele (OR, 0.98 [95% CI, 0.66-1.47]) or hay fever (OR, 1.11 [95% CI, 0.71-1.72]), nor with any other atopic outcome. CONCLUSION: We have found no evidence to suggest that prenatal alcohol exposure increases the risk of asthma or atopy in childhood