| Variable | Estimate | Range or alternative estimate | Comments |
|---|---|---|---|
| Rate of RSV-related admission | Actual data for 2009: number of admissions of healthy term infants*/population at risk in each region, January to June 2009 | Minimum estimate | 2009 had the lowest rates of RSV-related admissions documented in the previous 30 years.2-7 As other years are likely to have equal or greater rates of RSV infection, cost-effectiveness would be similar or greater. May be underestimate as only 90% were tested for RSV. |
| Births in 2009 | Actual number of births | - | Source: Statistics Canada or territorial governments |
| Healthy term infants | 0.92 of births in 2009 | - | Source: Dr. Maureen Baikie, Chief Medical Officer of Health, Government of Nunavut. In 2011-2013, 9.3% of the population received palivizumab each year (estimate 8% of those aged < 6 mo, 1.3% of those aged 6 mo-2 yr). |
| Population at risk | 51/72 of healthy infants | - | Infants born July 1, 2008, to May 31, 2009 |
| Population that received prophylaxis scenario A | 51/72 of healthy infants | - | Prophylactic administration of palivizumab to all infants born July 1, 2008, to May 31, 2009 (see Table 3) |
| Population that received prophylaxis scenario B | 6/12 of healthy infants | - | Prophylactic administration of palivizumab to infants < 5 mo of age (for 6 mo of protection) during RSV season (see Table 3) |
| Costs for RSV-related admissions | Actual cohort of admissions during 2009 RSV season | - | Included transportation, admission, physician fees and accommodation. No additional fees for resuscitation procedures, emergency visits, medications, outpatient follow-up, underestimating costs.10 |
| Cost of transportation to hospital | Actual amounts invoiced by medical evacuation companies for each medical evacuation | - | Source: medical evacuation companies/airlines |
| Cost of transportation back to home community | Equivalent of regularly scheduled economy flight | Minimum estimate | Source: directly from commercial airlines. Assumed return flight was economy commercial airlines, when sometime patients are transported by air ambulance with medical personnel. |
| Inpatient costs | Actual costs charged by hospital per day of hospital stay, differentiated by ward/ICU | - | Source: territorial governments, hospital finance departments |
| Physician cost | Estimated from OHIP Schedule of Benefits and Fees for pediatrics differentiated by day of admission, ward/ICU fees and whether mechanical ventilation required | - | This involves 9 hospitals where OHIP billings were mid-range. Exclusion of after-hours, emergency and procedural fees gives minimum estimates of costs. |
| Risk reduction | 96% | 88% scenario C | For preterm Inuit infants in Nunavut13 |
| Palivizumab cost | $225.75 per kg of estimated weight + 5% wastage + $50 administration | $225.75 per kg of estimated weight +15% wastage + $50 administration | Source: AbbVie Canada, as actual drug acquisition cost (see Table 3). Sensitivity analysis increases wastage threefold. Assumes vial sharing. |
| Estimated weight | Weight at 50% percentile for each month of age from CDC growth charts | - | CDC chosen rather than World Health Organization to have higher estimates of cost |
Note: CDC = US Centers for Disease Control and Prevention, ICU = intensive care unit, OHIP = Ontario Health Insurance Plan, RSV = respiratory syncytial virus.
*Without significant congenital heart or chronic lung disease.