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Vitamin A and Infant Mortality: Beyond Intention-to-Treat in a Randomized Trial

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Abstract

This paper investigates the effect of one dose of vitamin A on subsequent 4 month mortality in children under 6 months of age in a randomized, double-blind placebo-controlled community trial in Nepal. An earlier published intention-to-treat analysis showed no benefit, but ignored the information on actual receipt of treatment. Structural failure time models (Robins and Tsiatis, '91) use randomization based inference and incorporate compliance information which is possibly selective. The data presented here offer some new challenges for this approach: ward-based randomization induces correlation between survival outcomes; and the actual receipt of vitamin A dose is not always recorded. To tackle the problem of the clustered survival data we consider a robust version of the structural parameter vector estimator. A sensitivity analysis captures boundaries for the estimated structural parameters reflecting a range of potential values of children whose true receipt of treatment is unknown. The analysis suggests that the effect of vitamin A was beneficial in the beginning of the trial but towards the end of the trial there was a reversal of this effect.

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Authors and Affiliations

  1. National Public Health Institute, Mannerheimintie 160, 00300, Helsinki, Finland

    Pasi Korhonen

  2. Rolf Nevanlinna Institute, Helsinki University, P.O. Box 4, 00014, Helsinki, Finland

    Pasi Korhonen

  3. Dept. Applied Mathematics, University of Ghent, Krijgslaan 281, 9000, Ghent, Belgium

    Tom Loeys & Els Goetghebeur

  4. Mathematical Statistics, Stockholm University, S-10691, Stockholm

    Juni Palmgren

  5. Medical Epidemiology, Karolinska Institutet, S-17177, Stockholm, Sweden

    Juni Palmgren

Authors
  1. Pasi Korhonen
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  2. Tom Loeys
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  3. Els Goetghebeur
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  4. Juni Palmgren
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Korhonen, P., Loeys, T., Goetghebeur, E. et al. Vitamin A and Infant Mortality: Beyond Intention-to-Treat in a Randomized Trial. Lifetime Data Anal 6, 107–121 (2000). https://doi.org/10.1023/A:1009670105608

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  • DOI: https://doi.org/10.1023/A:1009670105608

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