Question 5: How might the data on time to roll over influence our interpretation of the results of this study?
The median time to roll over is less than the median time to start babywalker use. Hence many babies had the ability to roll over before their first use of a babywalker. Yet the difference in time to first roll over is highly significant and the estimated difference similar to other differences.
This suggests that the difference was present before the babywalkers and is not caused by them.
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Last updated: 23 October, 2006.
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