Table 1. Parameter Estimates for Cost-effectiveness of Solar-Powered O2 Systems and Direct Medical and Nonmedical Costs Associated With Hospitalization for Hypoxemia.
| Parameter | Base (range)a | Distribution | Reference |
|---|---|---|---|
| Factors for calculation of DALY | |||
| Annual No. of childhood pneumonia admissions (single health facility) | 431 (82-987) | Poisson | Nabwire et al,10 2018 |
| Proportion of patients admitted with pneumonia who are hypoxemic | 0.133 (0.093-0.375) | Beta | Subhi et al,1 2009 |
| Ratio of total hypoxemia cases: hypoxemic pneumonia cases | 1:0.66 (1:0.33-1:1.1) | Beta | McCollum et al,23 2013 |
| Hypoxemic pneumonia case fatality rate (with oxygen) | 0.089 (0.034-0.153) | Beta | Lazzerini et al,4 2015 |
| Relative risk reduction of mortality with oxygen | 0.35 (0.22-0.48) | Beta | Duke et al,6 2008 |
| Age of patient, y | 1.7 (0.0-5.0) | Gamma | Usen et al,24 1999 |
| Life expectancy, y | 59.2 (52.0-80.0) | Gamma | World Bank25 |
| Time on oxygen, d | |||
| Survivors | 4.00 (1.00-8.00) | Gamma | Nantanda et al,26 2014 |
| Fatal cases | 1.80 (0.14-15.00) | Gamma | Hawkes et al,19 2018 |
| Direct medical costs | |||
| Solar-powered oxygen system: photovoltaic cells (panels), batteries, and wiring | |||
| Hours of available sunlight | 5 (3-8) | Gamma | Hawkes et al,19 2018 |
| Price of solar panels, $/W | 2.92 (1.93-3.73) | Gamma | Turnbull et al,18 2016; Fu et al,27 2017 |
| Price of inverter | 1132 (566-1698) | Gamma | Hawkes et al,19 2018 |
| Price of charge controller | 1581 (790-2371) | Gamma | Hawkes et al,19 2018 |
| Required duration of backup battery supply | 48 (24-72) | Gamma | Hawkes et al,19 2018 |
| Price of batteries, $/Ah | 1.73 (0.61-3.47) | Gamma | Turnbull et al,18 2016; Rahman et al,28 2018 |
| Life span of batteries, y | 5 (2-8) | Gamma | Turnbull et al,18 2016 |
| Price of wiring and shelving | 1383 (691-2074) | Gamma | Hawkes et al,19 2018 |
| Price of labor and travel for installation | 1418 (709-2127) | Gamma | Hawkes et al,19 2018 |
| Life span of solar-powered O2 system, y | 10 (5-20) | Gamma | Turnbull et al,18 2016; World Health Organization20 |
| Oxygen concentrator | |||
| Price of oxygen concentrator, $ | 1026 (615-1352) | Gamma | Bradley et al,29 2015; Turnbull et al,18 2016; Hawkes et al,19 2018 |
| Oxygen concentrator power consumption, kW | 0.28 (0.23-0.33) | Gamma | Turnbull et al,18 2016; Hawkes et al,19 2018 |
| Life span of oxygen concentrator, y | 7 (2-10) | Gamma | Bradley et al,29 2015 |
| Annual maintenance cost of oxygen concentrator, $ | 669 (197-860) | Gamma | Bradley et al,29 2015; Turnbull et al,18 2016; Hawkes et al,19 2018 |
| Other direct medical costs | |||
| Cost of hospitalization for pneumonia, $/patient | 203 (152-255) | Gamma | Edejer et al,30 2005 |
| Nonmedical costs | |||
| Duration of admission, d | |||
| Survivors | 4 (1-8) | Gamma | Nantanda et al,26 2014 |
| Fatal cases | 1.80 (0.14-15.00) | Gamma | Hawkes et al,19 2018 |
| Daily household income, $ | 1.61 (1.06-2.10) | Gamma | Uganda Bureau of Statistics,39 |
| Distance traveled for treatment, km | 11.2 (5-80) | Gamma | Peterson et al,31 2004; Graham et al,5 2018; Idro and Aloyo32 2004 |
| Cost of transportation, $/km | 0.31 (0-1.04) | Gamma | Sadigh et al,33 2016; Matovu et al,34 2014 |
| Daily expenses (includes meals and accommodation for caregiver), $ | 2.99 (2.34-8.82) | Gamma | Sadigh et al,33 2016; Anderson et al,35 2017 |
Abbreviations: Ah, ampere hour; DALY, disability-adjusted life-year; solar-powered O2, solar-powered oxygen delivery.
a
All nominal costs adjusted to real costs in 2019 in US dollars.