Randomised controlled trial of perinatal vitamin D supplementation to prevent early-onset acute respiratory infections among Australian First Nations children: the 'D-Kids' study protocol.

INTRODUCTION: Globally, acute respiratory infections (ARIs) are a leading cause of childhood morbidity and mortality. While ARI-related mortality is low in Australia, First Nations infants are hospitalised with ARIs up to nine times more often than their non-First Nations counterparts. The gap is widest in the Northern Territory (NT) where rates of both acute and chronic respiratory infection are among the highest reported in the world. Vitamin D deficiency is common among NT First Nations neonates and associated with an increased risk of ARI hospitalisation. We hypothesise that perinatal vitamin D supplementation will reduce the risk of ARI in the first year of life. METHODS AND ANALYSIS: 'D-Kids' is a parallel (1:1), double-blind (allocation concealed), randomised placebo-controlled trial conducted among NT First Nations mother-infant pairs. Pregnant women and their babies (n=314) receive either vitamin D or placebo. Women receive 14 000 IU/week or placebo from 28 to 34 weeks gestation until birth and babies receive 4200 IU/week or placebo from birth until age 4 months. The primary outcome is the incidence of ARI episodes receiving medical attention in the first year of life. Secondary outcomes include circulating vitamin D level and nasal pathogen prevalence. Tertiary outcomes include infant immune cell phenotypes and challenge responses. Blood, nasal swabs, breast milk and saliva are collected longitudinally across four study visits: enrolment, birth, infant age 4 and 12 months. The sample size provides 90% power to detect a 27.5% relative reduction in new ARI episodes between groups. ETHICS AND DISSEMINATION: This trial is approved by the NT Human Research Ethics Committee (2018-3160). Study outcomes will be disseminated to participant families, communities, local policy-makers, the broader research and clinical community via written and oral reports, education workshops, peer-reviewed journals, national and international conferences. TRIAL REGISTRATION NUMBER: ACTRN12618001174279.

Feasibility and acceptability of the multi-component P3-MumBubVax antenatal intervention to promote maternal and childhood vaccination: A pilot study.

BACKGROUND: Pregnancy is a critical time for vaccine decision-making, but coverage remains suboptimal for maternal influenza (45-60%) and pertussis vaccination (65-80%) in Australia. The multi-component P3-MumBubVax intervention has been designed for Australian midwives to optimise antenatal vaccine discussions and improve maternal and childhood vaccine uptake. A pilot study was conducted to assess intervention feasibility and acceptability. METHODS: P3-MumBubVax includes components at three levels: 1. Practice ('vaccine champions'; stickers to prompt and record vaccine discussions/delivery); 2. Provider (website with vaccine communication training; learning exercise; fact sheets; links to child vaccination resources); 3. Parent (SMS reminders; website; fact sheets). Midwives and pregnant women 18-22 weeks gestation were recruited at the Royal Women's Hospital, Melbourne. Post-intervention online surveys assessed intervention feasibility, implementation, acceptability and impact on vaccine uptake. RESULTS: Twenty-five midwives and 62 pregnant women were recruited and 19/25 midwives completed training. Surveys were returned by 18/25 midwives and 56/62 women. 14/18 midwives reported using the sticker prompts, 10/18 reported using or referring to the website, and 11/18 reported using the fact sheets. 48/56 pregnant women (86%) reported discussing influenza and 46/56 (82%) discussed pertussis vaccines with their midwives. These conversations were reported to be short (1-3 min) for 48/56 women (87%). All midwives were satisfied with the intervention and 17/18 reported feeling more confident discussing vaccines following the intervention. Women were very satisfied with SMS content (50/56; 94%) and timing (49/55; 89%), and with their vaccine discussions in general (34/56; 63%). However, 16/54 (30%) wanted more discussion about childhood vaccines. Self-reported maternal vaccine uptake was 82% (45/55) and 93% (51/55) for influenza and pertussis (baseline 2017-2018: 43% influenza, 60% pertussis) and 96% (50/52) of infants were fully vaccinated at 12 weeks. DISCUSSION: The P3-MumBubVax intervention is feasible and acceptable in the Australian public antenatal setting. Further evaluation is required to determine effectiveness.

Discrete choice experiment to evaluate preferences of patients with cystic fibrosis among alternative treatment-related health outcomes: a protocol.

INTRODUCTION: Clinical decision-making is a complex process. Patient preference information regarding desirable health states should inform treatment and is critical to agreeing on goals of therapy. Cystic fibrosis (CF) is a common, inheritable multisystem disorder for which the major manifestation is progressive, chronic lung disease. Intermittent pulmonary exacerbations are a hallmark of disease and these drive lung damage that results in premature death. We suspect that clinicians make assumptions, most likely implicit assumptions, about outcomes that are desired by patients who are treated for pulmonary exacerbations. The aim of this study is to identify and quantify the preferences of patients with cystic fibrosis regarding treatment outcomes. METHODS AND ANALYSIS: We will develop a discrete choice experiment (DCE) in collaboration with people with CF and their carers, and evaluate how patients make trade-offs between different aspects of health-related status when considering treatment options. ETHICS AND DISSEMINATION: Ethics approval for all aspects of this study was granted by the Western Australia Child and Adolescent Health Service Human Research Ethics Committee [RGS903]. Weighted preference information from the DCE will be used to develop a multiattribute utility instrument as a measure of treatment success in the upcoming Bayesian Evidence-Adaptive Trial to optimise management of CF. Dissemination of results will also occur through peer-reviewed publications and presentations to relevant stakeholders and research networks.