A group of public health investigators queried 2 databases from the Consumer Product
Safety Commission (CPSC) to develop epidemiologic descriptors of window blind-related
injuries in children less than 6 years of age. First, they looked at the National Electronic Injury Surveillance System (NEISS), which collects injury information from a representative sampling consisting of about
100 hospital emergency departments. Second, they utilized the In-Depth Investigation
(IDI) database assembled from CPSC follow-ups of consumer complaints, media and medical
examiner reports, and other similar sources. An example of 1 of these reports is informative for those desiring a better understanding of
the type of data included.
The introduction to this study listed some important milestones in this topic. The
first report of a window blind injury in the medical literature apparently dates back to 1945.
In 1994, a window covering manufacturers' group announced a voluntary plan to eliminate
loops from blind pull cords and in 2000 announced a similar effort to address inner
cord loops in blinds. Hearing about that, I was interested to see how this might have
affected rates of such injuries. Much to my chagrin, the authors didn't tell me.
They found (from the NEISS data on an estimated 16,827 injuries) an overall rate of
2.7 injuries per 100,000 children per year over the study time period of 1990 to 2015.
However, they stated they couldn't hone down on rates in smaller time intervals due
to "potentially unstable" data for the annual estimates. They had a specific definition
of this term, but suffice to say that this is a problem with all subgroup analyses
that I've mentioned many times previously. Once one starts dividing up data groupings
into ever smaller units, the sample sizes become so small as to be misleading. Although
starting with over 16,000 injuries in 26 years seems like a number that would allow
some subgroup analysis, the numbers didn't meet the authors' predetermined limits
for statistical accuracy. They did provide a graph of numbers of injuries by year
that pretty clearly shows a stable number; they just couldn't convert this to accurate
Even not knowing exact rates, it is disheartening to see so many (several hundred
a year) window blind-related injuries in the NEISS database. Consumers and healthcare
providers should be aware of 2018 safety standards published by the Window Covering Manufacturing Association.