CHARACTERISTICS OF RESPONDERS AND NONRESPONDERS IN AN INFANT-FEEDING STUDY

Background Few studies have fully investigated and described the chara cteristics of non-responders in infant breast feeding studies. Examina tion of the characteristics of non-responders enhances this understand ing and provides information on the representativeness of the sample a ctually investigated. Methods As part of a larger local longitudinal s tudy, couples whose babies were due to be born during the three months of the study in the autumn of 1995, at two local maternity hospitals, were approached by midwives to participate in the study of infant fee ding patterns acid determinants, including interviews, questionnaires and postal survey. From the 648 eligible mothers, 91 (14 per cent) wer e not approached, 233 (35.9 per cent) consented but were not interview ed, 256 (39.5 per cent) consented and were interviewed and 68 (10.5 pe r cent) refused to participate (non-responders) in the longitudinal st udy. To make a comparison between the 'responders' (i.e. the 233 who c onsented but were not interviewed and the 256 who consented and were i nterviewed) and non-responders (the 68 who refused to consent), approp riate data were collected on their socio-demographic characteristics, their feeding intentions and their feeding behaviour. Results Univaria te analysis revealed a number of significant differences between respo nders and non-responders. However, log-linear analysis of these differ ences indicated that the main factors that differentiated between resp onders and non-responders were social class, smoking habit and actual feeding behaviour. When comparing the feeding intention at the time of 'booking', the non-responders compared with the responders were less likely to intend to breastfeed and more likely to be uncertain about t heir feeding intentions. Following delivery non-responders compared wi th responders were more likely to bottle feed their babies. By the tim e of discharge, of the non-responders, 83.6 per cent were bottle feedi ng in comparison with 47.3 per cent of responders who were also bottle feeding. Conclusions In this study non-responders were found to be mo re similar to bottle-feeding responders than to breastfeeding responde rs. Furthermore, non-responders were more likely to be smokers, from l ower social class and to bottle feed. This study also showed that the non-responders were more undecided about their feeding intention at th e time of the booking visit. Invariably a higher percentage of mothers who were undecided at the booking visit chose to bottle feed their ba bies at discharge. These results highlight the impact of failing to in clude information from non-responders when conducting research which e xamines patterns of infant breastfeeding and attitudes towards it.