Skip to main content

Saving lives with stem cell transplants


Blood stem cell transplants can be life-saving for some patients, but the chances of finding a matching donor are small unless a large number of potential donors are evaluated. Many nations maintain large registries of potential donors who have offered to donate stem cells if they are the best available match for a patient needing a transplant. An alternative source of stem cells, umbilical cord blood, is stored in banks. Everyone faces a small probability of needing a transplant which will increase their likelihood of survival. The registries and cord blood banks are thus an interesting example of a pure public good with widely dispersed benefits. This paper explores the gains in survival probability that arise from increased registry and bank sizes and uses value of statistical life methods to estimate benefits and compare them to costs. Our results suggest that for the United States and for the world as a whole, the sum of marginal benefits of an increase in either the adult registry or the cord blood bank exceeds marginal costs. However, marginal benefit-cost ratios for the adult registry are much greater than those for the cord blood banks, which suggests that to the extent that these two sources of life saving compete for public funds it may be preferable to prioritize expansion of the adult registry over cord blood banks.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4


  1. Formally, donor and recipient must have compatible human leukocytic antigen (HLA) types.

  2. The black population is even more genetically diverse. The probability that two randomly selected individuals are of matching type is less than one in 100,000.

  3. In a later paper, Gragert et al. (2014) used this data to estimate the likelihood of finding perfect matches and acceptable but less than perfect matches for individuals from several racial groups. They did not,however, conduct a benefit-cost analysis or investigate optimal registry sizes.

  4. Operationalizing these innovations required substantial computing resources. The optimum registry calculations were most intensive, requiring approximately 85 Gigabytes of RAM and nearly one week of computer processor time to complete using MATLAB. We are indebted to Wesleyan University for use of a high performance computing cluster that made this possible. The cluster is supported by the NSF under grant number CNS-0619508.

  5. An allele is an alternative form of a gene located at a specific position (genetic locus) in one’s DNA strand. Each locus contains two alleles, one inherited from each of the individual’s parents.

  6. Most of the work on HLA type distributions has treated Hispanic as a “race” rather than an “ethnicity.” We work with this data because it is what is available and use the term “racial group” or “race” to refer to the categories shown in the table. In addition, we hereafter use the term “U.S. Hispanic” since this classification is not made in other countries. Finally, we use the term “black” rather than “African-American” so that we can apply consistent racial labels across countries.

  7. A detailed country-by-country listing of the number of transplants performed, the number of adult donors registered, and the number of cord blood units can be found in Table A.1 of Appendix A. Table 2 excludes the Brazilian registry and cord banks. Although Brazil reports more than three million registrants, the country exported only 3 stem cell products in 2009 (World Marrow Donor Association 2009). We interpret this to mean there are substantial frictions preventing these registrants from being truly available to the remainder of the world. Because Brazil has a large population of African heritage, counting these registrants would have the effect of making the calculated matching probabilities for blacks much higher than is actually observed.

  8. Public data on HLA type distributions is divided into the racial/ethnic categories Caucasian, Black, Asian, and Hispanic but only the United States reports registry totals using these categories. To match the registry data with these categories, we included Pacific Islanders in the Asian category and Native Americans in the Caucasian category. Mixed race individuals were assigned to single races in proportion to the size of each single race group.

  9. For example, see Eapen et al. (2010) and compare Flomenberg et al. (2004) with Barker et al. (2010). Howard et al. (2008) also presented effectiveness scenarios in their sensitivity analysis in which the benefits of 5/6 and 6/6 cord blood transplants were greater than 7/8 adult donor ones, but maintained the preference for 7/8 adult donors in their search algorithm.

  10. Each phenotype can match as many as 8 others at a 7/8 match level; 6 others at a 5/6 match level; and 15 others at a 4/6 match level.

  11. Estimates of these probabilities from a search of U.S. banks alone are found in Appendix C.

  12. Appendix B shows the detailed calculations used to make these estimates.

  13. These figures are based on our estimates of the effects of adding a single registrant or cord blood unit. To make the tables more readily interpretable, we report estimated effects of adding 1,000 adult registrants or 100 cord blood units. The figures in the tables are calculated by multiplying the estimated effects of adding a single adult registrant by 1,000 and of adding a single cord blood unit by 100.

  14. Conditional on surviving five years, transplant recipients have life expectancy similar to that of the healthy population (Majhail and Rizzo 2013). The importance of this fact to valuing benefits is discussed in Section 5.1.

  15. Further discussions of this theory are found in Jones-Lee (1976), Drèze and Dehez (1982), Bergstrom (1982), and Hammitt (2007).

  16. The EPA website (U.S. Environmental Protection Agency. 2014) states a VSL of $7.4 million 2006 dollars, which equates to $8.55 million 2013 dollars.

  17. Howard et al. (2008) provide estimates from cord banks that: (1) 50% of collected units are too small and must be discarded; (2) the cost of processing a unit that is ultimately discarded is $500; and (3) the cost of processing a unit that is ultimately added to the bank is $1500. Together, these figures imply spending $2,000 for each newly banked unit.


  • Alberini, A. (2005). What is a life worth? Robustness of vsl values from contingent valuation surveys. Risk Analysis, 25(4), 783–800.

    Article  Google Scholar 

  • Aldy, J. E., & Viscusi, W. K. (2008). Adjusting the value of a statistical life for age and cohort effects. The Review of Economics and Statistics, 90(3), 573–581.

    Article  Google Scholar 

  • Anasetti, C., Hillgruber, R., Nye, V., Ayala, E., et al. (2010). Patient ethnicity markedly affects the probability of finding an HLA-A, -B,-C amd DRB 1 allele matched unrelated donor for hemopoietic cell transplantation. Biology of Blood and Marrow Transplantation, 16(2, Supplement 1), S172.

    Article  Google Scholar 

  • Ballen, K. K., Koreth, J., Chen, Y.-B., Dey, B. R., & Spitzer, T. R. (2012). Selection of optimal alternative graft source: Mismatched unrelated donor, umbilical cord blood, or haploidentical transplant. Blood, 119(9), 1972–1980.

    Article  Google Scholar 

  • Barker, J. N., Scaradavou, A., & Stevens, C. E. (2010). Combined effect of total nucleated cell dose and hla match on transplantation outcome in 1061 cord blood recipients with hematologic malignancies. Blood, 115(9), 1843–1849.

    Article  Google Scholar 

  • Bergstrom, T. (1982). When is a man’s life worth more than his human capital? In Jones-Lee, M. W. (Ed.) , The Value of Life and Safety (pp. 3–26). North Holland.

  • Bergstrom, T. C., Garratt, R., & Sheehan-Connor, D. (2009). One chance in a million: Altruism and the bone marrow registry. American Economic Review, 99 (4), 1309–1334.

    Article  Google Scholar 

  • Bergstrom, T. C., Garratt, R., & Sheehan-Connor, D. (2012). Stem cell donor matching for patients of mixed race. The B.E. Journal of Economic Analysis and Policy, 12(1).

  • Blomquist, G. C. (1979). Value of life saving: Implications of consumption activity. Journal of Political Economy, 87(3), 540–558.

    Article  Google Scholar 

  • Bone Marrow Donors Worldwide. (2014). Total number of stem cell donors. Available at, Accessed June 20, 2014.

  • Central Intelligence Agency. (2013). The World Factbook 2013-2014. Washington, DC.

  • de Blaeij, A., Florax, R. J., Rietveld, P., & Verhoef, E. (2003). The value of statistical life in road safety: A meta-analysis. Accident Analysis and Prevention, 35, 973–986.

    Article  Google Scholar 

  • Dehn, J., Buck, K., Yang, S., Schmidt, S., et al. (2010). 8/8 high-resolution match rate: Caucasian and African American patients. Biology of Blood and Marrow Transplantation, 17(2, Supplement 1), S170–171.

    Article  Google Scholar 

  • Drèze, J. H., & Dehez, P. (1982). State-dependent utility, the demand for insurance and the value of safety In Jones-Lee, M. W. (Ed.), , The Value of Life and Safety (pp. 41–65). North Holland.

  • Eapen, M., Rocha, V., Sanz, G., Scaradavou, A., Zhang, M.-J., Arcese, W., Sirvent, A., Champlin, R. E., Chao, N., Gee, A. P., et al. (2010). Effect of graft source on unrelated donor haemopoietic stem-cell transplantation in adults with acute leukaemia: A retrospective analysis. The Lancet Oncology, 11(7), 653–660.

    Article  Google Scholar 

  • Flomenberg, N., Baxter-Lowe, L. A., Confer, D., Fernandez-Vina, M., Filipovich, A., Horowitz, M., Hurley, C., Kollman, C., Anasetti, C., Noreen, H., et al. (2004). Impact of hla class i and class ii high-resolution matching on outcomes of unrelated donor bone marrow transplantation: Hla-c mismatching is associated with a strong adverse effect on transplantation outcome. Blood, 104(7), 1923–1930.

    Article  Google Scholar 

  • Gragert, L., Eapen, M., Williams, E., Freeman, J., Spellman, S., Baitty, R., Hartzman, R., Rizzo, J. D., Horowitz, M., Confer, D., & Maiers, M. (2014). Hla match likelihoods for hematopoietic stem-cell grafts in the U.S. registry. New England Journal of Medicine, 371(4), 339–348.

    Article  Google Scholar 

  • Gragert, L., Madbouly, A., Freeman, J., & Maiers, M. (2013). Six-locus high resolution hla haplotype frequencies derived from mixed-resolution dna typing for the entire us donor registry. Human Immunology, 74(10), 1313–1320.

    Article  Google Scholar 

  • Hammitt, J. K. (2007). Valuing changes in mortality risk: Lives saved versus life years saved. Review of Environmental Economics and Policy, 1(2), 228–240.

    Article  Google Scholar 

  • Health Resources and Services Administration. (2012). Detailed description of donor registry data. (Accessed March 12, 2013).

  • Health Resources and Services Administration. (2014a). Detailed description of donor registry data, Figure 3. (Accessed January 12, 2015).

  • Health Resources and Services Administration. (2014b). Donor registry data. (Accessed June 10, 2014).

  • Howard, D. H., Meltzer, D., Kollman, C., Maiers, M., Logan, B., Gragert, L., Setterholm, M., & Horowitz, M. M. (2008). Use of cost-effectiveness analysis to determine inventory size for a national cord blood bank. Medical Decision Making, 28(2), 243–253.

  • Jones-Lee, M. (1976). The value of life: An economic analysis. Chicago, IL: University of Chicago Press.

    Google Scholar 

  • Jones-Lee, M., Hammerton, M., & Philips, P. (1985). The value of safety: Results of a national sample survey. Economic Journal, 95, 49–72.

    Article  Google Scholar 

  • Knieser, T. J., Viscusi, W. K., Woock, C., & Ziliak, J. P. (2012). The value of a statistical life: Evidence from panel data. Review of Economics and Statistics, 94 (1), 74–87.

    Article  Google Scholar 

  • Kollman, C., Abella, E., Baitty, R., Beatty, P., Chakraborty, R., Christiansen, C., Hartzman, R., Hurly, C., Milford, E., Nyman, J., Smith, T., Switzer, G., Wada, R., & Setterholm, M. (2004). Assessment of optimal size and composition of the U.S. national registry of hematopoietic stem cell donors. Transplantation, 78(1), 89–95.

    Article  Google Scholar 

  • Kollman, C., Maiers, M., Gragert, L., Müller, C., et al. (2007). Estimation of HLA-A -B -DRB1 haplotype frequencies using mixed resolution data from a national registry with selective retyping of volunteers. Human Immunology, 68(12), 950–958.

    Article  Google Scholar 

  • Krupnick, A. (2007). Mortality-risk valuation and age: Stated preference evidence. Review of Environmental Economics and Policy, 1(2), 261–282.

    Article  Google Scholar 

  • Kurtzberg, J., Cairo, M. S., Fraser, J. K., Baxter-Lowe, L., Cohen, G., Carter, S. L., & Kernan, N. A. (2005). Results of the cord blood transplantation (coblt) study unrelated donor banking program. Transfusion, 45(6), 842–855.

    Article  Google Scholar 

  • Majhail, N., & Rizzo, J. D. (2013). Surviving the cure: Long term followup of hematopoietic cell transplant recipients. Bone Marrow Transplantation, 48(9), 1145–1151.

    Article  Google Scholar 

  • Miller, T. R. (2000). Variations between countries in values of statistical life. Journal of Transport Economics and Policy, 34(2), 169–188.

    Google Scholar 

  • Mishan, E. (1971). Evaluation of life and limb: A theoretical approach. Journal of Political Economy, 79, 687–705.

    Article  Google Scholar 

  • Mori, M., Beatty, P., Graves, M., Boucher, K., & Milford, F. (1997). HLA gene and haplotype frequencies in the North American population: The National Marrow Donor Program Donor Registry. Transplantation, 64, 1017–1027.

    Article  Google Scholar 

  • Schmidt, A. H., Sauter, J., Pingel, J., & Ehninger, G. (2014). Toward an optimal global stem cell donor recruitment strategy. PloS One, 9(1), e86605.

    Article  Google Scholar 

  • Seitz, R., Hilger, A., & Heiden, M. (2012). Bone marrow, peripheral blood, or umbilical cord blood: Does the source of allogeneic hematopoietic progenitor cells matter? Journal of Blood Disorders & Transfusion, S1(007).

  • Thaler, R., & Rosen, S. (1975). The value of saving a life: Evidence from the labor market. In Terleckyj, N. (Ed.) , Household Production and Consumption (pp. 265–300). New York: Columbia University Press.

  • UK Department for Transport. (2011). Updating the vpf and vpis: Phase 1: Final report. (Accessed July 16, 2014).

  • United States Census Bureau. (2014). Age and sec composition in the United States: 2012, table 1. (Accessed January 12, 2015).

  • U.S. Department of Transportation. (2013). Guidance on treatment of the economic value of a statistical life in U.S. Department of Transportation analyses. (Accessed July 4, 2014).

  • U.S. Environmental Protection Agency. (2014). Frequently asked questions on mortality risk valuation. (Accessed July 4, 2014).

  • Viscusi, W. K. (1978). Labor market valuations of life and limb: Empirical evidence and policy implications. Public Policy, 26(3), 359–386.

    Google Scholar 

  • Viscusi, W. K. (2013). Using data from the census of fatal occupational injuries to estimate the “value of a statistical life.” Monthly Labor Review, pp. 1–17.

  • Viscusi, W. K., & Aldy, J. (2003). The value of a statistical life: A critical review of market estimates throughout the world. Journal of Risk and Uncertainty, 27(1), 5–76.

    Article  Google Scholar 

  • World Marrow Donor Association. (2009). Stem cell donor registries annual report 2009. WMDA Publications.

Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to Damien Sheehan-Connor.

Additional information

The authors acknowledge support under NSF grant SES-0851357. In addition, we thank Wesleyan University for computer time supported by the NSF under grant number CNS-0619508. We also thank Martin Maiers of the National Marrow Donor Program for several useful discussions about this work. Chelsea Swete provided valuable research assistance. The views expressed in this paper are those of the authors and do not necessarily reflect those of the Federal Reserve Bank of New York or the Federal Reserve System.

Electronic supplementary material

Below is the link to the electronic supplementary material.

(PDF 198 KB)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Sheehan-Connor, D., Bergstrom, T.C. & Garratt, R.J. Saving lives with stem cell transplants. J Risk Uncertain 51, 23–51 (2015).

Download citation

  • Published:

  • Issue Date:

  • DOI:


  • Benefit-cost analysis
  • Transplantation
  • Matching
  • Donations
  • Stem cells

JEL Classifications

  • D61
  • H41
  • I11