Bath additives for the treatment of childhood eczema (BATHE): protocol for multicentre parallel group randomised trial

INTRODUCTION Bath emollients are widely prescribed for childhood eczema, yet evidence of their benefits over direct application of emollients is lacking. Objectives To determine the clinical and cost-effectiveness of adding bath emollient to the standard management of eczema in children METHODS AND ANALYSIS DESIGN Pragmatic open 2-armed parallel group randomised controlled trial. SETTING General practitioner (GP) practices in England and Wales. PARTICIPANTS Children aged over 12 months and less than 12 years with eczema, excluding inactive or very mild eczema (5 or less on Nottingham Eczema Severity Scale). INTERVENTIONS Children will be randomised to either bath emollients plus standard eczema care or standard eczema care only. OUTCOME MEASURES Primary outcome is long-term eczema severity, measured by the Patient-Oriented Eczema Measure (POEM) repeated weekly for 16 weeks. Secondary outcomes include: number of eczema exacerbations resulting in healthcare consultations over 1 year; eczema severity over 1 year; disease-specific and generic quality of life; medication use and healthcare resource use; cost-effectiveness. Aiming to detect a mean difference between groups of 2.0 (SD 7.0) in weekly POEM scores over 16 weeks (significance 0.05, power 0.9), allowing for 20% loss to follow-up, gives a total sample size of 423 children. We will use repeated measures analysis of covariance, or a mixed model, to analyse weekly POEM scores. We will control for possible confounders, including baseline eczema severity and child's age. Cost-effectiveness analysis will be carried out from a National Health Service (NHS) perspective. ETHICS AND DISSEMINATION This protocol was approved by Newcastle and North Tyneside 1 NRES committee 14/NE/0098. Follow-up will be completed in 2017. Findings will be disseminated to participants and carers, the public, dermatology and primary care journals, guideline developers and decision-makers. TRIAL REGISTRATION NUMBER ISRCTN84102309.