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Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India;
* Department of Child and Adolescent Health and Development, WHO, Geneva, Switzerland; and
Bloomberg School of Public Health, School of Hygiene and Public Health, Johns Hopkins University, Baltimore
2To whom correspondence should be addressed. E-mail: community.research{at}cih.uib.no.
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ABSTRACT |
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 TOP ABSTRACT SUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
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KEY WORDS: • complementary feeding • educational intervention • child growth • gender • cluster randomization
More than 60% of children living in South Asia are malnourished (1). Malnutrition increases the risk of child mortality; it is associated with >50% of child deaths (2) in addition to impairing child development (3). Identifying approaches to reduce the prevalence of malnutrition particularly in the vulnerable first 2 y of life is a priority in developing countries.
Malnutrition rates increase between 6 and 18 mo, the period of complementary feeding (4). Inappropriate practices such as the delayed introduction of complementary foods, low energy and nutrient density of foods offered, feeding in small amounts at meals, and food restrictions due to cultural beliefs are common even in parts of southeast Asia where incomes and food availability have improved steadily over the last decade (1). Other contributory factors for childhood malnutrition in young children are low birth weight and high morbidity (4).
An important public health question is whether educational programs to improve complementary feeding will accelerate the decline in undernutrition. Educational interventions were shown to improve feeding practices, but few of these studies were randomized controlled trials (5). Furthermore, studies tended to be on a small scale, and the strategies adopted may not be sustainable in primary health care systems that work under considerable resource constraints.
In this community-randomized controlled trial we evaluated an intervention that is likely to be sustainable even when applied on a large scale. The intervention was carefully designed, building on existing health and nutrition services, the involvement of a local nongovernment organization, and the specific feeding problems identified. We promoted recognition of malnutrition as a problem, complementary feeding initiation at 6 mo of age using foods that were available in homes and acceptable to mothers, appropriate portion size of feeds, optimal meal frequency and food density, and encouraging the child to eat. The effect of the intervention was measured on child feeding practices and growth between 6 and 18 mo of age. We also assessed whether promotion of appropriate complementary feeding practices had a differential effect in subgroups based on gender, caste, family income, and parental education. In the same trial, exclusive breast-feeding was promoted for the first 6 mo of life; those findings were reported separately (6).
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SUBJECTS AND METHODS |
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TOPABSTRACTSUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
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Primary health centers provide health care; each serves a population of 
30,000 through 2 or 3 medical officers, auxiliary nurse midwives, and other ancillary staff. There are 6 subcenters (population 5000) attached to each primary health center. Private practitioners trained in the biomedical or, more often, indigenous systems of medicine also serve this population. A local village based worker, the "Anganwadi worker," belonging to the Integrated Child Development Services Scheme (8) offers preschool education and a food supplement to the attendees at her home, the "Anganwadi Center." These services are used mainly for children > 3 y old because unlike younger children, they can be left at the center by themselves.
Intervention development. Formative research commenced in April 1998 and concluded with a baseline survey in all of the communities at the end of a year. Using qualitative research methods, information was sought on community characteristics, children’s nutritional status, and feeding practices. Insight was obtained into what foods were available in households, which foods were offered to young children, how often, and in what quantities. In addition, information was gathered on assistance provided to children while feeding and perceptions underlying appropriate or inappropriate feeding practices. Potential channels for the delivery of the intervention within the existing services were identified. The routine interactions of different categories of workers with families were observed to learn how they could be used for nutritional counseling without disrupting their other work. Feeding recommendations were developed using a standard approach that included assessment of child feeding practices, identification of common feeding problems, and locally appropriate ways to solve these (9). Household trials were conducted to test acceptability of different recommendations (9).
The nutrition recommendations were converted to nutrition messages in the local vernacular with the assistance of a communications agency. The channels for delivery of these messages and the points at which children would receive nutrition counseling were determined through interactive sessions with the workers and the district health and nutrition authorities.
The intervention. In the intervention communities, the opportunities used for counseling on complementary feeding were as follows: monthly home visits for new births until aged 12 mo and weighing once every 3 mo for children < 2 y old conducted by Anganwadi workers, immunization clinics run by the auxiliary nurse midwives, and sick child contacts with health care providers. The messages were also discussed at the monthly meetings conducted by the auxiliary nurse midwives with community representatives; these representatives held neighborhood meetings once a month with caretakers of children < 2 y old. Routine services were provided in the control sites. According to national policy, workers are required to advise on the initiation of complementary feeding at 4–6 mo, the types of foods to be fed, and the frequency of feeding. The formative research showed that home visits occurred occasionally and when they did, the focus was on family planning and immunization; only occasionally were recommendations given on foods that should be fed to young children. A previous assessment showed that Anganwadi workers had inadequate knowledge about appropriate child feeding practices (10).
Training of the health and nutrition workers in the intervention communities lasted for 3 d; 50% of the time was used for hands-on training. The training was based on the Integrated Management of Childhood Illnesses training manual on nutrition counseling and included imparting communication skills, detection of feeding problems, and negotiation with the mother on possible solutions that she would adopt among a locally adapted set of feeding recommendations (9,11). The intervention messages included starting complementary foods at 6 mo of age, the specific foods, meal frequencies and amounts to be fed at different ages while continuing to breast-feed, ways to encourage children to eat more, hand washing before a meal, and continuing feeding during illness (Table 1).
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Monitoring. The intervention delivery was monitored by the local authorities at the monthly reviews of health- and nutrition-related activities and they gave feedback to the workers. Consistent with an effectiveness design, the investigator’s role was restricted to measurement of specific outcomes by which the outcome was assessed.
Sample size. The number of communities required for this trial was determined using methods appropriate for community randomized trials (12). Data from the baseline survey in the 8 communities were used for making assumptions for the values in the control group and in estimating the inflation factors due to community randomization. Energy intakes for the control group (means ± SD) were 1003 ± 836 kJ at 9 mo and 2570 ± 1086 kJ at 18 mo with inflation factors of 1.31 and 1.32, respectively. Control weight and length at 12 mo were 7.8 ± 1.08 kg and 70.2 ± 2.9 cm with an inflation factor of 1.48 and 2.63, respectively.
A sample size of 450 infants per group enabled us to detect with 90% power and 95% confidence a 250-g difference in weight between the intervention and control groups and a 1-cm difference in length at 12 mo, a 50-kcal (209 kJ) increase in non-breast milk energy intake at 9 mo and a 100-kcal (418.4 kJ) increase at 18 mo of age.
Ethical approval. Before selection of the study sites, collaboration was sought from the local health and related authorities who became partners in the endeavor. The study had the approval of the ethics committees of the All India Institute of Medical Sciences and the WHO.
Randomization. A baseline survey was conducted in all households with children < 2 y old, and a total score was computed for each community on the bases of different socioeconomic indicators, child mortality and recent morbidity rates, and the prevalence of wasting and stunting. The 8 communities were paired on the basis of similar scores. To allocate 1 community of each pair to the intervention group, the 2 communities were listed in alphabetical order. A statistician, not involved with the study, generated 4 single-digit random numbers using a random numbers table; the first listed community in a pair was allocated to the intervention group if the random number was 0–4 and the second if it was 5–9.
Impact evaluation. Births occurring in the study villages were identified through Anganwadi workers and community informants from October 1999 to June 2000. Newborns were enrolled if they were local residents and informed written consent was obtained. A baseline form containing details of the child and family characteristics was also completed. Mothers and infants were visited at home by workers who were not involved in the delivery of the intervention at 3, 6, 9, 12, 15, and 18 mo of age to ascertain exposure to different channels, the details of counseling received at these contacts, and morbidity experienced by the infant in the 3 mo before the visit. Twice weekly visits were made for up to 1 mo in an attempt to contact those not available at a visit. Weights (using SECA scale, sensitivity 0.1 kg) and lengths (with locally manufactured infantometers, sensitivity 0.1 cm) were obtained at birth (if identified within 7 d) and at each of the 3 monthly home visits. Twenty-four hour dietary recalls were conducted by trained nutritionists at the 9 and 18 mo home visits.
Standardization exercises for inter- and intraobserver variability in weights and lengths were performed in which each child was measured twice (10 sets of 10 children each aged <2 y). The study commenced when all field workers obtained identical readings in both their weight measurements for a child and were in perfect agreement with the "gold standard" (a supervisor). For length, a difference of up to ± 0.5 cm between the readings of a field worker and the "gold standard" was considered acceptable. The 24-h non-breast milk energy intakes were estimated for 10 children by the 7 nutritionists available and the group mean was calculated for each child. The 3 nutritionists whose values were closest to the group mean were selected to conduct the recalls. They then conducted 24-h dietary recalls on 10 children each of age groups 0–6, 7–12, 13–18, and 19–24 mo until there was a 50-kcal (209 kJ) or less difference among nutritionists on the estimates for 5 consecutive children. The accuracy of weighing scales was checked daily against known standard weights and that of infantometers by using standard steel rods.
Analysis. A meal was defined as all of the foods eaten by the child within a 45-min interval. Diarrhea was defined as the passage of frequent loose or liquid stools or as the child suffering from "dast" (the local term for diarrhea) reported by the mother. Data were analyzed using Stata, version 6. All results reported are adjusted for cluster randomization (using the "cluster" option of the "regress" command) and for mothers working outside home, weights and lengths at 6 mo, and the breast-feeding status at 6 mo. For the 24-h dietary recall and anthropometry, odds ratios or differences in means with their 95% CI were estimated. All analyses were by intention to treat. Differences were considered significant at P < 0.05. Values presented in the text are means ± SD.
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RESULTS |
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TOPABSTRACTSUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
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Caretakers in the intervention communities reported being counseled more frequently at these contacts; the proportion who spontaneously recalled being counseled on optimal complementary feeding practices was 34 vs. 0.2% (P < 0.0001) at the immunization sessions, 43 vs. 0.5% (P < 0.0001) at home visits, and 36 vs. 0% (P < 0.0001) at the weighing sessions, in the intervention and control communities, respectively. Primary health center physicians or private practitioners rarely (1.5 vs. 0%; P = 0.02) counseled in this setting. When a visit to any of the above channels was considered, 444 (98.4%) children in the intervention communities had visited at least 1 potential source of complementary feeding counseling 1 or more times during the 6- to 9-mo period, and 344 (76.3%) had been counseled at least once. In the control communities, 393 (97.5%) children had visited a source, but only 3 had been counseled. The trends for exposure to different channels and the counseling received at age 18 mo were similar to those at 9 mo (data not shown). The exposure to different channels also did not vary by child’s sex (data not shown).
Effect on physical growth. Anthropometric data for the study groups at different ages were adjusted for cluster randomization, mother working outside the home, weight and length at 6 mo, and breast-feeding status at 6 mo (Table 3). Overall, the intervention did not affect the attained weights, the proportion of children with weight-for-age Z-score less than –2 SD at 12 and 18 mo, or the increments in weight between 6 and 12, and 12 and 18 mo. The crude and adjusted results were similar (Table 3).
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We decided a priori to examine the effect of the intervention in subgroups on the bases of gender, caste, income, and parental literacy. A test of interaction for comparison of means revealed a significant (P < 0.02) interaction between gender and the intervention effect on length at 12 mo of age (13). No significant interactions were found for caste, income, or parental literacy.
In the subgroup of male infants, the intervention resulted in a 0.51 cm higher attained length at 12 mo (95% CI, 0.03, 0.98, P = 0.039), a 0.51 cm greater length increment between 6 and 12 mo (95% CI, 0.03, 0.98, P = 0.039), and 8% fewer children with a height-for-age Z-score less than –2 SD (P = 0.391). Similarly, among males, the intervention resulted in a 0.37 cm higher attained length at 18 mo (95% CI, 0.08, 0.66, P = 0.02). In the subgroup of female infants, there were no significant differences or clinically relevant differences between the intervention and control groups.
Effects of the types of foods fed to children. Intakes of cereal legume gruels or mixes (i.e., cereals and legumes both cooked separately but mixed at the time of feeding), milk cereal gruels or milk cereal mixes (cereals cooked separately to which milk is added), and of undiluted milk were higher (P < 0.001) in 9-mo-old children in the intervention communities (Table 4). At this age, the recommended snacks were also fed more often (P < 0.0001) to children in the intervention communities. Similar patterns were seen at 18 mo, but the differences between the 2 groups were less pronounced for cereal legume gruels or mixes and for snacks than those at 9 mo, possibly because these are commonly given foods at this age (Table 4).
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The 24-h frequency of feeding non-breast milk meals and the total energy intakes from non-breast milk sources are shown in (Table 5). The meal frequencies (P = 0.001) and the energy intakes (P < 0.001) were higher in the intervention communities at 9 and 18 mo of age. The increase in energy intake was due to increased intake of milk, other foods, and the addition of extra oil to the food in the intervention communities at both 9 and 18 mo of age (Table 5).
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Responsive feeding and hygiene practices. At 9 mo, 34.8% mothers in the intervention group reported that they actively encouraged their child to eat more compared with 7.7% in the control group (P < 0.0001). At 18 mo, a higher proportion also reported encouraging their children to eat (89.7 vs. 49%; P < 0.0001). At this age, the practices that were reported more often in the intervention than the control communities included feeding with love and affection (41 vs. 11%; P < 0.0001), trying repeatedly if the child did not eat (15.4 vs. 1%; P < 0.0001), mother feeding the child herself (34.9 vs. 26.4%; P < 0.0001), making the child sit in the mother’s lap (18.2 vs. 6.6%, P < 0.0001), and feeding the child with other family members (12.4 vs. 2.5%; P < 0.0001). There was no interaction between gender and intervention effect on any of the responsive feeding behaviors (data not shown).
The proportion of mothers who reported washing their hands before feeding the child (94.5 vs. 59.9%; P < 0.0001) and their child’s hands before feeding (87.8 vs. 42.4%; P = <0.0001) was higher in the intervention group at 18 mo of age.
Morbidity experience. The reported prevalences of common illnesses in the previous 7 d did not differ in the 2 groups at 9, 12, 15, and 18 mo of age. At 12 mo of age, for instance, the prevalence of diarrhea was 16.8 vs. 13.1% (P = 0.174); cough 19.5 vs. 20.4% (P = 0.797); and fever 15.2 vs. 13.6% (P = 0.522) in the intervention and control communities. There was no interaction of gender with intervention effect on morbidity at any of the assessments.
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DISCUSSION |
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TOPABSTRACTSUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
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Several factors may have limited the intervention effect on physical growth. These include low consumption of foods of animal origin, gender-related differences in intervention effect, and the inability to reach some households repeatedly, or not at all. The diets of infants and young children in our setting were predominantly cereal based, and most children consumed only small amounts of milk (cross-sectional baseline survey, data not shown). It is also conceivable that intrauterine development due to maternal malnutrition or other stresses may have effects on growth in postnatal life that are not easily reversible. Further, a possible overreporting of intakes by caretakers may explain the discrepancy between the food intake and growth data. Dietary intakes, based on direct observations, were shown to be significantly lower than those estimated from 24-h recalls in intervention trials (14).
Intervention trials promoting education, coupled with effective communication strategies with or without food supplements, were reviewed by Caulfield (5). Five efficacy trials with supplemental food showed an additional 272–1254 kJ/d energy intake resulting in improvements in weight of 0.1–0.5 SD, and in 4 of these trials in which data were reported, from 0.04 to 0.35 SD in length (5).
Two recent efficacy trials in China and Brazil are of particular interest because nutritional counseling was given without food supplements (14,15). In these trials, locally appropriate complementary foods including foods rich in animal proteins and micronutrients were promoted. In the Chinese trial, intervention group infants were significantly heavier and longer at 12 mo of age (14), and the magnitude of the effect was greater than in our study. The consumption of foods of animal origin such as eggs, fish, chicken, or meat and of vegetables and fruits was more frequent in the Chinese study, and baseline weights and lengths of children were better (14). In the Brazilian trial, in which the intervention focused on children seeking care at health facilities, children 
12 mo of age had significantly improved intake of fats and in weight gain (15). There were no significant increases in overall energy and protein intakes or lengths (15). In a previous individually randomized Indian study, nutrition counseling did not affect the physical growth of children between 4 and 12 mo of age, whereas significant improvement in energy intakes was reported (16). Viewed together, the available studies suggest that the effect of educational interventions may vary depending on the baseline characteristics of the participants and other factors such as the types of foods available.
The observed effect on length and not on weight gain in this study warrants examination. There are some possible explanations worth considering. First, breast-feeding practices during the 6- to 9-mo period improved as a result of promoting exclusive breast-feeding during the first 6 mo of life and continued breast-feeding thereafter. Breast-feeding was reported to have a stronger effect on linear growth than on weight gain during late infancy and preschool years (17,18). Second, hygiene promotion was a part of the intervention, and improving hygiene and sanitation were also reported to improve linear growth (19). Third, the complementary foods whose reported intake was substantially increased were milk-based gruels or cereal-pulse mixes, which may improve nutrient quality in this setting (20).
This study has important implications for complementary feeding programs. Although it shows that educational interventions can improve feeding practices, the effect of such interventions on physical growth varies in different settings. Research should focus on explaining why the growth effect of nutritional interventions is limited in some regions such as south Asia. Finally, interventions that require behavior modification toward improving child feeding practices must pay greater attention to gender bias in such settings.
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ACKNOWLEDGMENTS |
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FOOTNOTES |
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3 Other Members of the Infant Feeding Study Group: Dr. Sunita Taneja, Ms. Brinda Nayyar, Ms. Vandana Suri, Ms. Poonam Khokhar, and Dr. Tivendra Kumar, Department of Pediatrics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi-29, India; Dr. R. C. Agarwal, Faridabad, Government of Haryana, India; Dr. S. K. Sharma, BK Hospital, Faridabad, Haryana, India.
Manuscript received 3 May 2004. Initial review completed 31 May 2004. Revision accepted 11 June 2004.
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LITERATURE CITED |
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TOPABSTRACTSUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
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1. World Health Organization (2002) Global forum for health research. Child health research: a foundation for improving child health 2002 WHO Geneva, Switzerland. www.who.int/child-adolescent-health/New_Publications/CHILD_HEALTH/GC/WHO_CFH_CAH_02.3.pdf [last accessed May 2004].
2. Pelletier, D. L. (1994) The relationship between child anthropometry and mortality in developing countries: implication for policy, programs and future research. J. Nutr. 124:2047S-2081S.
3. World Health Organization (1999) A Critical Link. Interventions for Physical Growth and Psychological Development: A Review. Document ref WHO/CHS/CAH/99.3 1999 WHO Geneva, Switzerland.
4. Waterlow, J. C. (1988) Observations on the natural history of stunting. Linear Growth Retardation in Less Developed Countries 1988:5-8 Nestle Nutrition S.A Vevey, Switzerland.
5. Caulfield, L. E., Huffman, S. L. & Piwoz, E. G. (1999) Interventions to improve intake of complementary foods by infants 6 to 12 month of age in developing countries: impact on growth and on the prevalence of malnutrition and potential contribution to child survival. Food Nutr. Bull. 20:183-200.
6. Bhandari, N., Bahl, R., Mazumder, S., Martines, J., Black, R. E. & Bhan, M. K. (2003) Effect of community based promotion of exclusive breast feeding on diarrheal illnesses and growth—a cluster randomized controlled trial. Lancet 361:1418-1423.[Medline]
7. International Institute for Population Sciences (India) and ORC Macro (2000) National Family Health Survey (NFHS-2), 1998–99 2000 IIPS Mumbai, India.
8. Integrated Child Development Services Scheme (Revised) (India) 1982 Ministry of Social Welfare, Government of India New Delhi, India. Available on URL: http://wcd.nic.in/udisha/htm/abouticds.htm [last accessed May 2004].
9. World Health Organization, Division of Child Health and Development (1997) Integrated Management of Childhood Illness: Adaptation Guide. Working Draft, Document ref WHO/CHD/97–3E Version 3 1997 WHO Geneva, Switzerland.
10. Kapil, U., Sood, A. K. & Gaur, D. R. (1992) Nutritional beliefs amongst Anganwadi workers. Indian Pediatr. 29:67-71.[Medline]
11. World Health Organization (1997) Integrated Management of Childhood Illness 1997 WHO Geneva, Switzerland.
12. Donner, A., Birkett, N. & Buck, C. (1981) Randomization by cluster: sample size requirements and analysis. Am. J. Epidemiol. 114:906-914.
13. Pocock, S. J. (1983) Clinical Trials: A Practical Approach 1983 John Wiley & Sons New York, NY.
14. Guldan, G. S., Fan, H. C., Ma, X., Ni, Z. Z., Xiang, X. & Tang, M. Z. (2000) Culturally appropriate nutrition education improves infant feeding and growth in rural Sichuan, China. J. Nutr. 130:1204-1211.
15. Santos, I., Victoria, G. C., Martines, J., Goncalves, H., Gigante, P. D., Valle, J. N. & Pelto, G. (2001) Nutrition counseling increases weight gain among Brazilian children. J. Nutr. 131:2866-2873.
16. Bhandari, N., Bahl, R., Nayyar, B., Khokhar, P., Rohde, J. E. & Bhan, M. K. (2001) Food supplementation with encouragement to feed it to infants from 4 to 12 months of age has a small impact on weight gain. J. Nutr. 131:1946-1951.
17. Onyango, A. W. (2000) Breastfeeding and growth in rural Kenyan toddlers. Adv. Exp. Med. Biol. 478:151-162.[Medline]
18. Onyango, A. W., Esrey, S. A. & Kramer, M. S. (1999) Continued breastfeeding and child growth in the second year of life: a prospective cohort study in western Kenya. Lancet. 354:2041-2045.[Medline]
19. Esrey, S. A., Habicht, J. P. & Casella, G. (1992) The complementary effect of latrines and increased water usage on the growth of infants in rural Lesotho. Am. J. Epidemiol. 135:659-666.
20. World Health Organization (1998) Complementary Feeding of Young Children in Developing Countries: a Review of Current Scientific Knowledge. Document ref WHO/NUT/98.1 1998 WHO Geneva, Switzerland.
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