Lestina’s total estimate of net savings, comes from increased costs of hospitalization. One assumption that leads to these savings is problematic. This assumption concerns individuals who, had there been a poison control center, would have been treated at home but, absent a center, go to the emergency department. It is assumed that these individuals will have the same probability of hospitalization and the same hospitalization costs as experienced by the whole population of individuals who are hospitalized for poisoning. If this assumption is not valid, the resulting analysis will overestimate the savings attributable to poison control centers.
On the other hand, there are some cost-saving features of poison control center systems not taken into account by Miller and Lestina. For example, Miller and Lestina used total center costs (e.g., including education), not costs associated with telephone-based case management. Also, better health outcomes for cases that did need to go to the emergency department (e.g., Harrison et al., 1996) were not taken into account. Thus, while the widely quoted figure from Miller and Lestina (1997) of a 6.5-to-1 cost savings for investments in poison control centers is not outside the bounds found in other studies, their methodology makes their particular conclusion problematic.
All of the above analyses focus on tangible cost savings associated with poison control centers. In such analyses, intangible psychological benefits to the public of such centers are not considered. Yet parents and caregivers often experience lowered levels of anxiety if they are able to call the centers and be reassured, when warranted, that a trip an emergency department is not necessary, and they are subsequently advised about how to treat the situation at home. There is also the comfort of knowing that this service exists even if one does not use it. These intangible benefits are hard to quantify.
One study that considers these psychological benefits is Phillips et al. (1997). The researchers asked individuals who had called a poison control center and members of the public what they would be willing to pay to have a center to which they could have access. A wide range of methodological concerns can be raised about hypothetical answers to willingness to pay that are given by members of the public without the benefit of deep reflection and thoughtful calculation of intangible and tangible benefits; nonetheless, the results are informative. For those who had called a poison control center, the average willingness to pay to have a center was $6 to $7 per month, or $72 to $84 per year; for members of the public, the results were an average of $2.55 per month, or about $30 per year. The willingness to pay these figures can be compared with the actual cost per person in service area of a treatment management guidance function, which Zuvekas et al. (1997) estimated to range from 22 to 58 cents per year. Thus, Phillips and colleagues (1997) found a difference of at least 50