Child Drowning

In the case-control study, swimming ability was defined as whether a child was able to swim 25 metres
across a pond, using any stroke or motion. The association with swimming ability raised the possibility
that if children are taught to swim once old enough they may be protected from drowning. However,
the data came from a single case-control study that showed only an association with protection and not
a causative relationship between swimming and protection from drowning. The inability to show a
cause and effect relationship is a methodological limitation of case control studies. A review of the
drowning literature in HICs did not provide an answer to the question of whether swimming ability
reduced drowning in children: studies showed an association, none showed a causal relationship.
Moreover, the studies with an association had significant limitations such as small sample sizes,
questions of recall validity and different definitions of swimming ability. Most of the studies were
carried out among populations with very different water exposure rates than populations in the LMICs
surveyed. 43
Case control studies examining swimming ability (with the same 25 metre definition) as a protective
factor were repeated in Cambodia and Thailand, with the results shown in Table 8.
Table 8: Odds ratios for association of swimming ability and drowning protection, children aged 5-17
Survey country, name and date Odds Ratio (95% confidence interval)
Bangladesh (BHIS 2003) 4.5 (1.3-19.2)
Thailand (TNIS 2004) 3.4 (1.3-8.8)
Cambodia (CAIS 2007) 3.1 (0.6-16.2)
Combined (BHIS, TNIS,CAIS)* 2.7 (1.3-5.5)
Source: Survey data from countries included in the surveys.
*Wald chi square confidence intervals significant to the 5 per cent level.
Odds ratio has been adjusted for the survey.
The elevated odds ratios for the studies was significant (p< 0.05), showing that naturally acquired
swimming ability for children aged 5 years and over was associated with protection from drowning. One
additional survey conducted in Aceh, Indonesia after the 2004 Indian Ocean tsunami provides evidence
for the association of swimming ability and protection from drowning. 44
43
Brenner R. A. et al. (March 2009). ‘The association between swimming lessons and drowning in childhood: A case-control study’. Archives of
Pediatrics and Adolescent Medicine, 163(3):203-210; Gilchrist J, J. Sacks and C. Branche (1994). ‘Self reported swimming ability in adults’, 1994,
Public Health Reports, vol. 115, 110-111; Yang L et al. ‘Risk factors for childhood drowning in rural regions of a developing country: A case–
control study’. Injury Prevention, 13(3):178-182.
44 The Aceh Tsunami Study was a retrospective cohort study. A total of 3,568 households, with a population of 16,240 members located within 5
kilometres from the beach where the tsunami wave/s swept ashore were enrolled. Swimming ability of the household residents, including
caretakers of young children, was determined along with their survival status (dead or alive) after submersion in the tsunami wave/s. The study is
a subject of a separate working paper in this series.
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