Surveys Yield Conflicting Trends in U.S. Pet Ownership
A new article from the Veterinary Information Network highlights the importance of understanding research methodologies in evaluating the results of different studies. In this particular case, the authors examine the discrepancy between cat and dog populations in concurrent surveys carried out by the American Veterinary Medical Association (AVMA) and the American Pet Products Association (APPA). With some of their findings differing by margins as high as 19%, the results show a significant disparity that can end up with a completely different takeaway message.
Animal advocates often rely on statistics and survey numbers to support their advocacy efforts, but how do we know that the numbers we’re using are accurate and actionable? What if one survey tells you that pet ownership is waning, while another, ostensibly of the same country at the same time, tells you pet ownership is at an all-time high? This is just what happened in 2014 with studies from the AVMA and APPA. Though the authors of this analysis note that their numbers “have never matched exactly in 17 years of their asking similar questions in pet ownership surveys of American households,” the most recent gaps are a chasm stretching wider than ever. This is not just a problem for advocates, however. “From the perspective of veterinarians, if the number of pets is increasing, then demand for veterinary services conceivably will rise. Conversely, if the number is shrinking, then demand conceivably will fall. Which way demand is headed is especially pertinent to the profession today owing to concerns about an excess of companion animal veterinarians in the United States.”
All this begs the question: why are the numbers so wildly different? To better understand, the authors at VIN examined the methodologies of both groups (including the kinds of samples taken and the questions posed) and consulted experts in polling. On the level of basic structure, it’s hard to see why the numbers are so skewed: “For its surveys, the AVMA hires Irwin Broh Research, while the APPA contracts with Ipsos. […] Both have fairly high numbers of respondents. In the most recent polls, 50,347 responded to the AVMA; 25,109 responded to the APPA. By comparison, public opinion and political polls such as the CBS News Poll typically survey roughly 1,000 people.” More respondents should mean that the margin of error in their results is smaller, but one survey expert who commented on the results notes that “both surveys are likely to produce unreliable results in part due to their use of online panels, which he said can give skewed samples of the population. […] Online methods don’t reach significant chunks of the population, particularly older and low-income households. At least 15 percent of American adults do not use the Internet, according to a 2013 report by the Pew Research Center.” Based on this alone, it becomes very difficult to obtain a truly random, representative sample, even with large response rates. Likewise, depending on the types of questions asked, responses can vary and skew the numbers: “Asking ‘Do you have any pets now?’ and ‘How many pets have you had during the past 12 months?’ could elicit different answers. […] In fact, The AVMA asks two questions: whether a household owned a pet on Dec. 31 of the previous year, and whether a household owned a pet at any point in the previous calendar year. APPA asks whether a household currently owns a pet.” Two different organizations, ostensibly seeking the same kinds of answers, can get very different results based on their questions.
How do animal advocates parse this information and incorporate it into their advocacy? While some of the experts interviewed for the article note that if you stick with one organization’s numbers over several surveys, you can still see basic trend information, the variance among them is a valid cause for concern. The best that most advocates will be able to do with this warning is make a note that these survey results can speak to trends, but can also be misleading overall. We should pay attention to the methods of surveys before incorporating their results into our advocacy work.
Original Abstract:
Not Available
http://news.vin.com/VINNews.aspx?articleId=31369