ABC News reports on how easy it is for children to defeat child resistant tops on medication bottles. As ABC News notes,
There’s no such thing as child-proof bottles and child-resistant means that the majority of children under 5–some 85 percent–cannot open it in under 5 minutes, according to the Consumer Product Safety Commission.
Unfortunately, ABC didn’t even bother to explore the truly interesting question–do child resistant bottle caps save lives and, if so, how many?
Child resistant caps were first required in the United States in the early 1970s and originally were mandated for bottles of aspirin. But how well do they prevent child poisoning?
W. Kip Viscusi presented a paper at the 1984 meeting of the American Economic Association suggesting that such caps weren’t the panacea they might at first seem.
Viscusi looked at rates of child poisonings from aspirin beginning from when the mandate first went into effect in 1972, and there was indeed a decline in aspirin poisonings afterward. However, Viscusi argued the decline wasn’t all it was cracked up to be.
In 1971 aspirin was responsible for a fatal poisoning rate of 2.6 per million children under age 5, and by 1980 this rate had dropped to 0.6. The overall aspirin poisoning rate exhibited a similar drop, from 5.0 to 1.7 per 1,000. While these declines were dramatic, after taking into account the trend in aspirin poisonings and the decline in aspirin sales in the 1970’s, there is no statistically significant impact of the regulation
Moreover, Viscusi notes an oddity in the data. Manufacturers of aspirin were apparently allowed to market one size of aspirin without the child resistant cap, and according to Viscusi firms “typically…chose the best selling size”. So there would then be aspirin poisonings caused by children getting access to bottles that had child resistant caps as well as children poisoned after taking pills from bottles that lacked the caps.
The surprising thing is that the aspirin poisonings occurred disproportionately with the child resistant versions,
Whereas 40 percent of all aspirin poisonings in 1972 were from safety cap bottles, this figure rose to 73 percent by 1978.
Viscusi concedes that this could be due to families without children being more likely to select the non-safety cap versions and households with children opting for the child-resistant caps. However, he notes that something strange happened with poisoning rates with other analgesics at the same time.
Analgesic poisoning rates for children under age 5 escalated from 1.1 per 1,000 in 1971 to 1.5 per 1,000 in 1980. Even after taking into account increases in analgesic sales, 47 percent of this increase is attributable to an unexplained upward shift in the analgesic rate beginning in 1972. The coupling of the absence of any shift in the trend of aspirin poisoning rates with an upsurge in analgesic poisoning rates is consistent with the hypothesis that there is a significant indivisibility in safety precautions. Moreover, absence of a significant effect of safety caps on aspirin poisonings and the 47 percent unexplained shift in analgesic poisonings suggest that the impact of the regulation on balance was counterproductive, leading to 3,500 additional poisonings of children under age 5 annually from analgesics.
. . . A more likely explanation for these dramatic effects is that consumers have been lulled into a less-safety-conscious mode of behavior by the existence of safety caps. The presumed effectiveness of the technological solution may have induced increased parental irresponsibility.
Viscusi’s paper has been much cited over the years, and is conclusions have occasionally been disputed.
A 2002 paper by Gregory B. Rodgers published in the Archives of Pediatric and Adolescent Medicine concluded that,
After controlling for covariates, the use of child-resistant packaging was associated with a 34% reduction in the aspirin-related child mortality rate. This mortality rate reduction equates to the prevention of about 90 child deaths during the 1973-1990 postregulatory study period.
One of the oddities of the debate is how few studies have been done to investigate whether the 1972 mandate was effective in reducing aspirin poisonings given how ubiquitous of an intervention that child resistant packaging has become. Rodgers noted in his paper that as of 2002, there had been only two other studies attempting to quantify the effect of the mandate on aspirin poisonings.