Table 1.

Illustrative example of parameter uncertainties, alternative assumptions, and sensitivity analyses

Assumption	Alternative assumption	Sensitivity analysis
Mark-up % similar for all services assuming linear relation between direct and indirect costs	CVD prevention patients might ‘consume’ less building and overhead costs because they are seen in an outpatient setting	Decrease building mark-up% and traditional overhead mark-up% by 20%
Pharmacy staff and administrative staff in indirect costs, assumes that time spent per patient is similar for all patients	CVD prevention patients might use more pharmacy resources: almost all patients on drugs and often complicated drug regimes. Similar consideration for record staff (searching for files of chronic patients)	Increase ‘context-specific’ overhead including records and pharmacy mark-up% by 20%
CVD consultation: doctor costs based on salary average medical staff	In this setting there is a lack of doctors. In private clinics, the medical director tends to run also patient clinics. In OOH, usually three doctors including the medical director attend to all patients	Use both medical director salary (1/3) and regular doctor salary (2/3) to value costs per minute for a doctor
Productive working hours based on contract hours	Certain staff such as doctors are overburdened and work many more hours per week	Increase productive work hours by 20%
Interest rate=16% (Central Bank)	Local interest rate in rural setting for entrepreneurs might be much higher (personal communication: can be up to 25%)	Vary by 20%
Building value: estimated to be 8% of building maintenance	No other data available	Vary building value mark-up by ±20%

CVD: cardiovascular disease; OOH: Ogo Oluwa Hospital.