Table 2 Summary of model variables
Description | Base Value | Low Value | High Value | Method or assumption (range for sensitivity analysis) | Reference or source |
|---|---|---|---|---|---|
Unit costs | |||||
Cost per general ward day public | 3,727.35 | 1,863.68 | 5,591.03 | Average weighted expenditure per patient day equivalent (± 50 %) | [19] |
Cost per ICU day public | 17,844.88 | 8,922.44 | 26,767.31 | Average weighted expenditure per patient day equivalent inflated using private tariff differential (± 50 %) | Assumption |
Tariff per general ward day private | 5,251.66 | 2,625.83 | 7,877.48 | Published tariff rates (± 50 %) | [18] |
Tariff per ICU day private | 25,142.55 | 12,571.28 | 37,713.83 | Published tariff rates (± 50 %) | [18] |
Utilisation | |||||
LoS in general ward in severe patients | 21.25 | 7.25 | 43.00 | Literature review (IQR) | |
LoS in ICU in critical patients | 8.80 | 4.30 | 13.30 | Literature review (IQR) | |
LoS in general ward in critical patients in absence of ICU | 8.80 | 4.30 | 13.30 | Assumed to be the same as critical patients treated in ICU | Assumption |
LoS in general ward in critical patients before/after ICU | 1.00 | 0.00 | 3.00 | Literature review (IQR) | [12] |
Proportion needing ICU | 0.21 | 0.05 | 0.50 | Literature review (low and high value) | |
Proportion reliant on public health system | 0.83 | 0.42 | 1.00 | Percentage of population without Medical Scheme coverage (-50 %;1) | [28] |
Mortality rates | |||||
Proportion of severe patients dying | 0.11 | 0.00 | 0.13 | Literature review (low and high value) | |
Proportion of critical patients dying from ICU | 0.54 | 0.24 | 0.88 | Literature review (low and high value) | |
Proportion of critical patients dying without access to ICU | 0.88 | 0.70 | 1.00 | Assumed high value on critical patients dying from ICU (-20 %;1) | Assumption |
DALYs | |||||
Disability weight in severe patients | 0.13 | 0.09 | 0.19 | Disability weight for severe lower respiratory tract infection (95 % CI) | [22] |
Disability weight in critical patients | 0.41 | 0.27 | 0.56 | Disability weight for severe pneumoconiosis (95 % CI) | [22] |
Duration of illness in severe patients | 0.13 | 0.06 | 0.19 | 1.5 months (± 50 %) | Assumption |
Duration of illness in critical patients | 0.17 | 0.08 | 0.25 | 2 months (± 50 %) | Assumption |
Duration of illness prior to death | 0.04 | 0.02 | 0.06 | 0.5 months (± 50 %) | Assumption |
Years of life lost if dying from COVID-19 | 5.40 | 2.70 | 8.10 | 5.4 years (± 50 %) | [21] |
Other | |||||
Cost-effectiveness threshold per DALY averted | 38,465.46 | Used to assess value for money; if ICER < CET intervention potentially cost-effective | [7] | ||