Sacks, J. J., Kresnow, M., & Houston, B. (1996). Dog bites: how big a problem? Injury Prevention: Journal of The International Society For Child And Adolescent Injury Prevention, 2(1), 52-54.
National Canine Research Council Summary and Analysis:
This paper is included as the first of only two broad national randomized telephone surveys of dog bite incidence in the United States. Over 20 years ago Sacks et al. (1996) extracted data on dog bite incidence from a national telephone health survey, the CDC Injury Control and Risk Survey (ICARIS). This report and the follow up published in 2008 (Gilchrist et al.) provide the most widely cited incidence reports on the topic. The authors estimated that approximately 4.7 million people had been bitten by a dog during the first survey year (1994), and that approximately 800,000 of those bites had been presented for medical care. Despite the subsequent ubiquity of these findings in the literature, these studies have limitations including: very broad ranges in confidence intervals (the result of very small numbers of bites actually reported by the respondents), particularly with injurious bites; reliance on long term memory of relatively minor events in most cases (generally considered to be unreliable); low response rates (56%); estimates of incidence for one age group (15 to 17 year olds) without data; and no contextual data collected regarding the circumstances of the bites. The incidence level reported here, while much higher than any of those based on dog bites reported to authorities, (e.g., Matthias et al., 2015) still works out to ≤ 9% of the estimated 1994 dog population of ~52 million (Wise et.al., 2002) delivering even a very minor bite and ≤ 1% delivering a bite for which medical treatment was sought.
The researchers reported that a higher proportion of children were treated for their bites. Sacks et al. (1996) suggested that this was because the children’s bites were more serious, but there is no supporting evidence for this claim in their study. The finding could also be attributed to parents feeling a greater sense of concern about any injury to their children than to themselves or other adults. Severity differences between children and adults simply cannot be determined from this study’s self-reported data. Moreover, when this study was replicated a decade later (see Gilchrist et al., 2008) the elevated incidence of bites to children vs. adults was reversed.
From the 186 bites (94 for adults, 92 for children) reported by approximately 5,300 households, the authors extrapolated to 4.7 million bites annually in the entire country. Similarly, the 38 who required medical treatment were extrapolated to 756,000 in the population. These are enormous leaps, especially considering the recall bias concerns and lack of a definition of what constituted a bite.
The authors’ conclusion that, “…dog bites merit far more attention as a remediable public health problem” seems at best subjective when compared to other injury modalities reported by the CDC that affect much larger proportions of the population. For example, dog bites account for far fewer injuries annually than riding bikes, tripping, and playing sports (Centers for Disease Control and Prevention, 1997).
In sum, the small incidence sample, long recall period, and lack of definition of a bite suggest that the uncritical reliance upon these findings as definitive with regard to dog bite, or dog bite-related injury, prevalence may not be supportable. Fortunately, at least with regard to injurious bites, the CDC maintains an Emergency Department based injury tracking system that is available to the interested public. The CDC’s Web-based Injury Statistics Query and Reporting System (WISQARS) records injuries presented for treatment at emergency departments around the country. A report on data from an earlier version of this survey system for 1992-94 (Weiss et al. 1998), while less comprehensive than Sacks et al. (1996), provides a useful comparison with both this survey study and the subsequent replication (Gilchrist et al., 2008).
Link to Full Text of Original Article:
Centers for Disease Control and Prevention, Web-based Injury Statistics Query and Reporting System (WISQARS), Non-fatal injury reports, 2001-2014. Available at: http://webappa.cdc.gov/sasweb/ncipc/nfirates2001.html
Wise, J.K, Heathcott, B.L., Gonzalez, M.L. (2002). Results of the AVMA survey on companion animal ownership in US pet-owning households. American Veterinary Medical Association. JAVMA, 221(11), 1572–3.