Breast-feeding Performance Index: a composite index to describe overall breast-feeding performance among infants under 6 months of age Upul Senarath 1 , Michael J Dibley 2, *† and Kingsley E Agho 3 1 Department of Community Medicine, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka and Visiting Fellow, University of Newcastle, Callaghan, New South Wales, Australia: 2 Centre for Clinical Epidemiology and Biostatistics, Faculty of Health, University of Newcastle, Callaghan, New South Wales, Australia: 3 School of Public Health, University of Sydney, Sydney, New South Wales, Australia Submitted 14 December 2005: Accepted 19 October 2006: First published online 27 February 2007 Abstract Objectives: To develop a composite index to describe the overall breast-feeding performance of infants , 6 months of age; and, using this index, to identify the factors associated with poor breast-feeding practices and the association between breast- feeding and infant morbidity. Design, setting and subjects: The 2003 Demographic and Health Survey was a multi- stage cluster sample survey of 4320 households in Timor-Leste which covered 573 infants aged , 6 months. Breast-feeding Performance Index (BPI) was constructed by allocating one point for each of seven infant feeding practices: first suckling within an hour of birth; absence of prelacteals; non-use of feeding bottles; current breast- feeding; not receiving liquids; not receiving formula or other milk; and not receiving solids in the last 24 hours. BPI was treated as the dependent variable in univariate and multivariate analyses to identify the factors associated with poor breast-feeding. Results: Exclusive breast-feeding rate was 29.9%. The BPI (mean 4.4, standard deviation 1.77) was categorised as low, average and high according to tertiles. Multivariate analysis indicated that infants from the richest households were 1.70 (95% confidence interval (CI) 1.04 – 2.77) times more likely to have ‘low BPI’ than the poorest. Maternal BMI , 18.5 kg m 22 was predictive of poor breast-feeding (odds ratio ¼ 1.79; 95% CI 1.27–2.52). In the ‘low’ BPI group, the incidence of diarrhoea (13.4%) and acute respiratory infections (20.7%) during the previous two weeks was significantly higher than in ‘average’ (4.3 and 9.3%) and ‘high’ BPI groups (4.6 and 5.5%). Conclusions: Creating a composite index to assess the overall breast-feeding performance among infants , 6 months of age is feasible. BPI can be effectively used to identify target groups for breast-feeding promotion interventions. Keywords Breast-feeding Infant feeding Sociodemographic factors Infant nutritional status Timor-Leste Composite child feeding indices are becoming increas- ingly important in the measurement of health outcomes of feeding practices, identification of determinants of poor feeding performance and evaluation of the effectiveness of nutritional interventions 1–3 . The main advantage of creating an index is that it can capture multiple dimensions of infant feeding practices into a single summary variable that can be used in the analyses of relationships with potential risk factors or health outcomes 3 . However, most previous research on associations between breast-feeding practices and health outcomes of infants have only considered the individual breast-feeding indicators such as exclusive breast-feeding, full breast-feeding and bottle- feeding rates 4–6 . A large body of literature discusses predictive or risk factors of breast-feeding performance in different parts of the world, and the majority of these studies also focused on individual dimensions of breast- feeding 7–9 . Breast-feeding status among infants , 6 months of age constitutes several dimensions including timely initiation, exclusiveness, and whether or not the infant is given prelacteal feeds and bottle-feeds. The World Health Organization (WHO) infant feeding guidelines *Corresponding author: Email michael.dibley@newcastle.edu.au q The Authors 2007 †Correspondence address: Centre for Clinical Epidemiology & Biostatistics, Room 353, David Maddison Clinical Sciences Building, Royal Newcastle Hospital, Newcastle, New South Wales 2300, Australia. Public Health Nutrition: 10(10), 996–1004 doi: 10.1017/S1368980007441428