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Search Result: 2 Records found

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Mass deworming for improving health and cognition of children in endemic helminth areas: A systematic review and individual participant data network meta-analysis
  • Authors Vivian A. Welch, Elizabeth Ghogomu, Alomgir Hossain, Alison Riddle, Michelle Gaffey, Paul Arora, Omar Dewidar, Rehana Salaam, Simon Cousens, Robert Black, T. Déirdre Hollingsworth, Sue Horton, Peter Tugwell, Donald Bundy, Mary Christine Castro, Alison Eliott, Henrik Friis, Huong T. Le, Chengfang Liu, Emily K. Rousham, Fabian Rohner, Charles King, Erliyani Sartono, Taniawati Supali, Peter Steinmann, Emily Webb, Franck Wieringa, Pattanee Winnichagoon, Maria Yazdanbakhsh, Zulfiqar A. Bhutta, George Wells
  • Published date 2019-11-21
  • Coordinating group(s) International Development, Nutrition
  • Type of document Review Plain language summary
  • Title Mass deworming for improving health and cognition of children in endemic helminth areas: A systematic review and individual participant data network meta-analysis
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/full/10.1002/cl2.1058
  • English

    PLAIN LANGUAGE SUMMARY

    Mass deworming programs have little effect on nutritional status and cognitive development on a population level

    The effectiveness and cost-effectiveness of mass deworming of children to improve child health and other outcomes is debated. This independent analysis reinforces the case against mass deworming at a population-level, finding little effect on nutritional status or cognition. However, children with heavier intensity infections may benefit more.

    What is this review about?

    Soil-transmitted helminthiasis (STH) and schistosomiasis affects over 800 million people. There is ongoing debate about whether mass deworming of children improves child nutritional status and cognitive development in endemic areas.

    What is the aim of this review?

    This Campbell systematic review evaluates what factors modify the effects of mass deworming for soil-transmitted helminths on nutritional status and cognition in children in endemic helminth areas using individual participant data.

    What studies are included?

    Randomized trials of mass deworming for soil-transmitted helminths (alone or in combination with other drugs or child health interventions) for children aged six months to 16 years were eligible if they reported at least one of the following outcomes: growth, haemoglobin, serum ferritin, or cognitive processing or development. Trials had to collect data on baseline STH infection intensity, since the main purpose of this review was to assess effect modification across intensity of infection.

    Individual participant data was obtained from 19 out of 41 eligible randomized trials. These 19 trials included 31,945 participants) and had an overall low risk of bias.

    A secondary analysis added new data to the meta-analysis of STH deworming vs placebo of a previous Campbell review by the same authors. This analysis included 29 randomized trials, with data from two studies which had not published weight gain data and updated effect estimates from three studies based on the data provided by the authors.

    These studies were conducted in 11 low- and middle-income countries. Most programs conducted deworming every four months or more frequently. Seven out of 19 studies gave a single dose of deworming.

    Children were school-age, with a median of 11 years of age.

    Does deworming improve child health and other welfare outcomes?

    Mass deworming for soil-transmitted helminths compared to placebo probably has little to no effect on nutritional status or cognitive development (moderate certainty evidence). Children with moderate to heavy intensity infections of A Lumbricoides or T Trichiuria may experience greater weight gain (very low certainty evidence). No other differences in effects were found across age, sex or baseline nutritional status.

    Findings are consistent for studies at low risk of bias and for other methodological considerations such as completer analyses. There was no trend in effect according to publication year, baseline A Lumbricoides prevalence or T Trichuria prevalence in the full dataset of 29 studies. Higher baseline hookworm prevalence was weakly associated with greater effects of STH deworming.

    What are the implications of this review for policymakers and decisionmakers?

    This analysis replicates the prior findings of small effects of mass deworming at the population level. In areas where there are children with moderate to heavy intensity infections, which are increasingly uncommon, mass deworming may be beneficial, but this analysis was limited by the small number of children with heavy intensity infections in this sample (fewer than 1,000).

    In areas with light intensity infections, mass deworming programs probably have very small effects on weight for these children and additional policy options need to be explored to improve child health and nutrition in these areas.

    What are the research implications of this review?

    This analysis was severely limited by not being able to obtain individual participant data for many older studies, which may have included children with heavier intensity infections. Greater adoption of calls for open, structured data from trials could maximize the benefit of research to understand effects in the most vulnerable and marginalized populations within these trials.

    How up-to-date is this review?

    The review authors searched for studies up to March 2018.

Food supplementation for improving the physical and psychosocial health of socio-economically disadvantaged children aged three months to five years
  • Authors Elizabeth Kristjansson, Damian K Francis, Selma Liberato, Maria Benkhalti Jandu, Vivian Andrea Welch, Malek Batal, Trisha Greenhalgh, Tamara Rader, Eamonn Noonan, Beverley J. Shea, Laura Janzen, George A. Wells, Mark Petticrew
  • Published date 2015-05-04
  • Coordinating group(s) International Development, Nutrition, Social Welfare
  • Type of document Review Plain language summary
  • Title Food supplementation for improving the physical and psychosocial health of socio-economically disadvantaged children aged three months to five years
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2015.11
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Food supplementation is more effective if better targeted and supervised

    Supplementary food has a small effect on nutritional outcomes. It is more effective for younger and poorer children, when provided in day-care or feeding centres than as take home rations, when the supplemental food provides higher energy and when there is stricter program supervision. There is a positive effect on psychomotor development, but no clear evidence of an effect on cognitive development.

    What did the review study?

    Undernutrition is a severe problem, especially low and middle-income countries, where it contributes to the death of a million children each year. It also increases the risks of lowered cognitive functioning, poor school performance and poor health. Supplementary feeding programs aim to close the energy gap from poor nutrition. They provide additional food or beverages with a high energy level to be consumed alongside regular meals.

    This review examines whether food supplementation is effective in improving the health of disadvantaged children aged 3 months to 5 years, and examines the factors that contribute to the effectiveness of food supplementation programs.

    What is the aim of this review?

    This Campbell systematic review examines whether food supplementation is effective in improving the health of disadvantaged children under 5. The review summarizes findings from 32 studies: 21 randomised controlled trials (RCTs), and 11 controlled before-and-after studies (CBAs).

    What studies are included?

    Studies included in this review compare the effects of supplementary food on children’s physical and psychosocial health to no-feeding or a placebo. Feeding programs could be implemented through day-care, feeding centres, or in the home, though those in a hospital setting were excluded.

    The review includes 32 studies, 21 randomised controlled trials (RCTs) and 11 controlled before-and-after studies (CBAs). The majority of the included studies (29) are conducted in low- and middle-income countries.

    What were the main findings of the review?

    Is supplementary food effective in improving the health of disadvantaged children under five?

    Supplementary feeding for young, disadvantaged children has small effects on children’s weight and growth in low- and middle-income countries. Children who are younger, and poorer or more undernourished grow more in response to supplementary feeding.

    More leakage occurs from take home rations. Therefore, food supplementation programs implemented through day care centres seem to be more effective, as are those with stricter supervision.

    Both single and multiple interventions were effective for weight gain in children but the effect size for multiple interventions was higher. The effect is also higher for higher energy meals.

    There is a positive effect on psychomotor development, which is development of skills that require both mental and muscular activity (such as crawling, walking, talking). However, there was no clear evidence of an effect on cognitive development.

    What do the findings in this review mean?

    Targeting and strict supervision may increase the effectiveness of food supplementation programs.

    The supplement should contain at least 30 per cent of the recommended daily intake. Consideration should also be given to providing rations for other family members to avoid leakage.

    There is a need to fund additional trials to examine the impact of supplementary feeding on the psychosocial development of young, disadvantaged children. More research is also needed on the implementation of high-quality interventions and large-scale programmes for supplementary feeding.

    How up-to-date is this review?

    The review authors searched for studies until January 2014.

  • Spanish

    Click on 'Download PDF' on the right to view the plain language summary in Spanish.

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