Separate analysis will be conducted to compare the high intensity arm to the control arm and the low intensity arm to the control arm, and subsequent analysis will include comparing the low intensity arm to the high intensity arm as well as adjustment of the primary analysis by potential confounding characteristics such as race and age, to account for potential biases in the randomization.
Assuming a 10% loss to follow-up these power calculations are based on a sample size of 180 in each of the three arms, assuming two Chi square tests will be conducted; one to compare the low intensity arm to the control arm and one to compare the high intensity arm to the control arm.
Where data were reported separately for sub-groups, for example men and women, the groups were combined for the meta-analysis, and if trials were three-armed only the higher intensity arm was included, for example intervention delivered face-to-face rather than by telephone.
Only the higher intensity arm was considered in two (19, 28), and in the third the arm that incorporated weight loss drugs was excluded to leave just the behavioural arm (33).
Small experimental and uncontrolled studies have suggested hemodynamic and survival benefits at higher doses of HVHF than those used for the high-intensity arms of the RENAL and ATN studies.
After discussion, we believed this study fulfilled eligibility based on the rationale that the prescribed dose for this study was only marginally lower than the high-intensity arms of the RENAL and ATN trials, which prescribed a lower effluent dose and did not show improved outcome [ 8, 9, 28].
A recent post hoc analysis of a nested cohort of 115 patients from the RENAL study demonstrated that those in the higher-intensity arm (40 ml/kg per hour) had improved blood pressure and decreased vasopressor requirements in the absence of other changes that might explain the effect, such as acid base or temperature differences compared with the control arm [ 48].
The 'Cervical Cancer Screening and Adherence to Follow-up Among Hispanic Women' study is a parallel randomized controlled trial with participants randomized into a control or usual care arm; a high intensity intervention 'Promotora' plus video arm; or a low-intensity 'video' only arm.
This study includes three arms: a high intensity exercise programme, a low-to-moderate intensity exercise programme, and a waiting list control group.
We will randomize about 600 women (anticipated 200 per arm to each of 3 arms; control, low intensity intervention, high intensity intervention) into the study, which will allow for 10% attrition.
