Randomised controlled trial of thermostatic mixer valves in reducing bath hot tap water temperature in families with young children in social housing: A protocol

Denise Kendrick¹ , Jane Stewart¹^,2 , Carol Coupland¹ , Michael Hayes³ , Nick Hopkins⁴ , Debbie McCabe⁴ , Robert Murphy⁵ , George O'Donnell⁶ , Ceri Phillips⁷ , David Radford⁸ , Jackie Ryan⁹ , Sherie Smith¹ , Lindsay Groom¹ and Elizabeth Towner¹⁰

¹Division of Primary Care, Floor 13, Tower Building, University of Nottingham, University Park, Nottingham, NG7 2RD, UK

²Nottingham Primary Care Research Partnership, Nottinghamshire County Teaching PCT, Hucknall Health Centre, Curtis Street, Nottingham, NG15 7JE, UK

³Child Accident Prevention Trust. 4th Floor, Cloister Court, 22–26 Farringdon Lane, London, EC1R 3AJ, UK

⁴Glasgow Housing Association, Granite House, 177 Trongate, Glasgow, G1 5HF, UK

⁵East End Community Homes, 1221 Gallowgate, Unit 60, The Forge Shopping Centre, Glasgow, G31 4EB, UK

⁶City Building (Glasgow) Limited Liability Partnership (LLP), Milton Service Centre, 450 Ashgill Road, Glasgow, G22 6HJ, UK

⁷Institute for Health Research, Swansea University, Singleton Park, Swansea, SA2 8PP, UK

⁸NHS Greater Glasgow and Clyde NHS, Dalian House, 350 St. Vincent Street, Glasgow, G3 8YZ, UK

⁹East End Child Safety Project, 503 London Road, Glasgow, G40 1NQ, UK

¹⁰Centre for Child and Adolescent Health, University of the West of England, Hampton House, Cotham Hill, Bristol, BS6 6JS, UK

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Trials 2008, 9:14doi:10.1186/1745-6215-9-14


Published:	19 March 2008

Abstract

Background

Each year in the UK 2000 children attend emergency departments and 500 are admitted to hospital following a bath water scald. The long term effects can include disability, disfigurement or psychological harm and repeated skin grafts may be required as the child grows. The costs of treating a severe scald are estimated at 250,000 GBP. Children living in the most deprived wards are at greatest risk of thermal injuries; hospital admission rates are three times that for children living in the least deprived wards.

Domestic hot water, which is usually stored at around 60 degrees Celsius, can result in a second-degree burn after 3 seconds and a third-degree burn after 5 seconds. Educational strategies to encourage testing of tap water temperature and reduction of hot water thermostat settings have largely proved unsuccessful. Legislation in the USA mandating pre-setting hot water heater thermostats at 49 degrees Celsius was effective in reducing scald injuries, suggesting passive measures may have a greater impact. Thermostatic mixer valves (TMVs), recently developed for the domestic market, fitted across the hot and cold water supply pipes of the bath, allow delivery of water set at a fixed temperature from the hot bath tap. These valves therefore offer the potential to reduce scald injuries.

Design/Methods

A pragmatic, randomised controlled trial to assess the effectiveness of TMVs in reducing bath hot tap water temperatures in the homes of families with young children in rented social housing. Two parallel arms include an intervention group and a control group where the intervention will be deferred.

The intervention will consist of fitting a TMV (set at 44 degrees Celsius) by a qualified plumber and provision of educational materials. The control arm will not receive a TMV or the educational materials for the study duration but will be offered the intervention after collection of follow-up data 12 months post randomisation.

The primary outcome measure will be the bath hot tap water temperature. Fifteen families per arm are required to detect a reduction in the mean bath hot tap water temperature from 60.4 degrees Celsius (SD 9.1) in the control group to 46 degrees Celsius in the intervention group, with 90% power and a 5% significance level (2 sided). Secondary outcome measures including acceptability will require a sample size of 120 participants.

Discussion

Whilst TMVs have the potential to reduce scald injuries, to date there have been no randomised controlled trials assessing their effectiveness, acceptability and cost effectiveness.

Trial Registration

ISRCTN21179067