The cost of operating a needle exchange program was estimated in the University of California/Centers for Disease Control and Prevention report (Lurie et al., 1993a). Briefly, their report noted wide variation in annual cost across the 18 programs sampled, ranging from $18,628 in the Tacoma Pharmacy Exchange to $393,951 in the Lower East Side, New York City, Exchange. The median annual cost of operating a needle exchange was $168,650. The budgets reflect actual plus donated resources for personnel, consultants, equipment, supplies, transportation, travel, and space rental. The proportion of the budget specifically allocated to syringes ranged from 2 percent in Boston and New Haven to 47 percent in the Tacoma Pharmacy Exchange (median = 7 percent), with the proportion per program reflecting the volume of needles exchanged. The largest proportion of the budget was for personnel, ranging from 27 percent in Berkeley's NEED exchange to 79 to 80 percent in the Boulder, New Haven, and Portland exchange programs (median = 66 percent).
In an attempt to measure the productivity of needle exchange programs, the University of California team of investigators used the annual budget, the number of participant contacts, the number of syringes distributed, and the hours of operation for each program to calculate the cost per participant contact, the cost per syringe distributed, and the cost per hour open. The median cost per participant contact across the seven programs with available data was $17; the median cost per syringe distributed was $1.35; and the median cost per hour of program operation was $145. The median number of syringes distributed per hour was 205.
The variability across sites was attributed to differences in exchange rates of needles: higher costs per needle, contact, and hours of operation were related to activities that do not contribute directly to needle exchange. For example, Boston's ACT-UP project spent considerable time attempting to engage a scattered clientele under continual police scrutiny and had exchanged 9 syringes per hour, considerably below the median of 205.
In an attempt to measure the cost-effectiveness of programs, the University of California research team estimated absolute impact (number of HIV infections averted) and associated cost-effectiveness (program cost divided by number of HIV infections averted) on the basis of three different models. The three models included a simplified circulation model formula (Kaplan, 1993), a behavior change model (Kahn et al., 1992), and a combined circulation and behavior change model (Lurie et al., 1993a:496-499). The results summarized here are based on a hypothetical needle exchange program with specific characteristics (e.g., high volume of needle exchange, limited counseling and referrals to other services) and HIV risk determinants (e.g., high prevalence and incidence, drug and sexual risk behaviors).