Costs

Details of the derivation and calculation of the costs used in these analyses are given as supplementary information (S1 File). The costs are broken down as follows:

Capital costs: These are the costs of purchasing the equipment necessary to run the mobile team or the HAT screening at a fixed unit. Capital costs are calculated using the straight line depreciation method over a 5-year useful life for mobile teams and 20 years for fixed health facilities. Total annual capital costs for a mobile team were 12,001 and 12,781 USD for mobile teams implementing CATT and RDTs respectively, and 551 and 496 USD for a fixed health facility for CATT and RDTs respectively.

Annual recurrent costs: For mobile teams, these include the costs of staffing the unit for one year (staffing costs for fixed health facilities are calculated on a per test basis), the costs of training, insurance and maintenance. Total costs for mobile teams are 30,307 USD / year and 435 USD / year for fixed health facilities.

Daily running costs: These include the costs of consumables such as fuel, water and stationery. For mobile teams, they also include the allowances paid to staff. For mobile teams, the total costs are 97 USD per screening day (21,340 USD / year) and for fixed health facilities 3.50 USD per screening day (875 USD / year or 0.35 USD per patient screened, based on screening 10 patients per day).

Staffing costs for fixed health facilities: The cost for a laboratory technician is 0.78 USD / hour and 0.63 USD / hour for a nurse based on national salaries. We assume that the consultation at a fixed health facility is with a nurse, although in practice this could occasionally be with a doctor.

The costs of materials (including shipping) for the diagnostic tests are: CATT_WB is 0.70 USD in mobile teams and 0.76 USD in fixed facilities (the cost at the fixed facility includes a small loss due to repeating control tests), RDT 0.60 USD (0.85 excluding a 0.25 USD subsidy, but including 0.1 USD shipping cost), CATT dilutions 3.02 USD; LN 0.38 USD; mHCT 1.54 USD; mAECT 7.20 USD; materials for CSF examination are 2.00 USD.

The time required to perform each test was (in minutes): clinical consultation 20; CATT_WB 10; RDT 17; CATT dilutions 15; aspiration of lymph nodes and examination of aspirate 15; mHCT 18; mAECT 30; examination of CSF 30.

We included costs incurred by individuals presenting for screening, including travel costs and costs of missed work. These were 0.32 USD for mobile teams and 1.97 USD for fixed health facilities.