Objective: The objective of this study was to quantify and characterize the role of bath seats in infant mortality from bathtub drowning.
Method: Risk analysis of bathtub drowning deaths for infants aged 6-10 months was performed using data available from the US Consumer Product Safety Commission (CPSC), birth and mortality data from the National Center for Health Statistics (NCHS) for US resident infants from 1990-1998, and bath seat ownership from the American Baby Group and industry sales data compiled by NPD to estimate bath seat use. The analysis computes the relative risks of infant drowning based on estimates of bath seat use with a cohort design and explores the potential confounding by a range of factors.
Results: In-depth analysis of the unintentional bathtub drowning deaths of American infants aged 6-10 months for the years 1994 through 1998 revealed 40 infant drowning deaths associated with bath seats and 78 deaths not associated with bath seats. Based on available data on sales and use that suggest approximately 45% of infants in this age group use bath seats, the existing data do not support a hypothesis that bath seats increase the risk of bathtub drowning for infants. Bath seats are not intended or marketed as safety devices, and analysis of the existing, albeit limited, data suggests that they either have no effect or they may provide some slight unexplained protection against unintentional bathtub drowning risks (with an odds ratio for the risk of drowning with a bath seat vs without a bath seat of approximately 0.6 [95% confidence interval (CI) 0.4-0.9]). Although all potential confounders cannot be fully explored due to incomplete data and large uncertainties remain, this analysis suggests that the US CPSC made the appropriate decision not to ban bath seats in response to petitions it received in 1994 and 2001.
Conclusions: Increasing market sales and surveys of reported bath seat use were associated with decreasing unintentional infant bathtub drowning risks. Rigorous risk analyses should be conducted when considering regulating products to ensure that regulation does not inadvertently increase injury risks. Analysis of the factors associated with these deaths suggests that additional efforts are needed to ensure that caregivers do not leave infants unattended in the bathtub and to collect data that will further improve our understanding and management of these risks.