Table 2.
Model inputs of probabilities, costs and utilities
| Variable name | Description | Base-case value | Distribution (standard deviation) | Reference |
|---|---|---|---|---|
| CMM parameters | ||||
| _stage | Number of cycles simulated | 20 | -- | Predefined value |
| cycle_length | Duration of one cycle | 3 months | -- | Predefined value |
| discount_rate | Discount rate for cost values | 0.004 | -- | Deutsche Bundesbank88 |
| discount_rate_QALY | Discount rate for QALYs | 0.004 | -- | Deutsche Bundesbank88 |
| p_getDiGA | Proportion of total patient cohort using a DiGA |
Treatment 2: 0.0154 Treatment 3: 0.5 |
-- |
Treatment 2: GKV Spitzenverband52 |
| Cohort size | Total cohort size represents amount of people in Germany with self-reported diagnosis of depression | 4,977,172 | -- | Grobe et al.76, Statistisches Bundesamt77 |
| Proportion of starting cohort | ||||
| p_mild | Proportion of cohort starting in the mild depression health state | 0.257 | -- | Stahmeyer et al.78 |
| p_moderate | Proportion of cohort starting in the moderate depression health state | 0.484 | -- | Stahmeyer et al.78 |
| p_severe | Proportion of cohort starting in the severe depression health state | 0.259 | -- | Stahmeyer et al.78 |
| p_remis | Proportion of cohort starting in the remission health state | 0.000 | -- | Predefined value |
| p_death | Proportion of cohort starting dead | 0.000 | -- | Predefined value |
| Transition probabilities | ||||
| pwo_mild_mild |
Transition probabilities of treatment 1: Without DiGA scenario (pwo) Codification according to the following scheme pwo_a_b, where a indicates the health state of the current cycle and b the health state in the next cycle |
0.717 | Calculated* | Stahmeyer et al.78 |
| pwo_mild_moderate | 0.055 | Beta (0.006) | Stahmeyer et al.78 | |
| pwo_mild_severe | 0.022 | Beta (0.002) | Stahmeyer et al.78 | |
| pwo_mild_remis | 0.200 | Beta (0.020) | Stahmeyer et al.78 | |
| pwo_mild_death | 0.005 | Beta (0.001) | Statistisches Bundesamt89,90 | |
| pwo_moderate_moderate | 0.774 | Calculated* | Stahmeyer et al.78 | |
| pwo_moderate_mild | 0.027 | Beta (0.003) | Stahmeyer et al.78 | |
| pwo_moderate_severe | 0.047 | Beta (0.005) | Stahmeyer et al.78 | |
| pwo_moderate_remis | 0.147 | Beta (0.015) | Stahmeyer et al.78 | |
| pwo_moderate_death | 0.005 | Beta (0.001) | Statistisches Bundesamt89,90 | |
| pwo_severe_severe | 0.787 | Calculated* | Stahmeyer et al.78 | |
| pwo_severe_mild | 0.021 | Beta (0.002) | Stahmeyer et al.78 | |
| pwo_severe_moderate | 0.091 | Beta (0.009) | Stahmeyer et al.78 | |
| pwo_severe_remis | 0.094 | Beta (0.009) | Stahmeyer et al.78 | |
| pwo_severe_death | 0.006 | Beta (0.001) | Statistisches Bundesamt89,90 | |
| pwo_remis_remis | 0.495 | Calculated* | Stahmeyer et al.78 | |
| pwo_remis_mild | 0.129 | Beta (0.013) | Stahmeyer et al.78 | |
| pwo_remis_moderate | 0.242 | Beta (0.024) | Stahmeyer et al.78 | |
| pwo_remis_severe | 0.130 | Beta (0.013) | Stahmeyer et al.78 | |
| pwo_remis_death | 0.005 | Beta (0.001) | Statistisches Bundesamt89,90 | |
| pwo_death_death | 1.000 | -- | ||
| pDiGA_mild_mild |
Transition probabilities of treatment 2 and 3: With DiGA scenario standard of care/future (pDiGA) Codification according to the following scheme pDiGA_a_b, where a indicates the health state of the current cycle and b the health state in the next cycle |
0.627 | Calculated* |
Stahmeyer et al.78; Klein et al.11; Meyer et al.91; Moritz et al.92,93; Krämer et al.24; Beiwinkel et al.94; Baumeister & Moritz95 See Supplementary Table 3 for overview of included DiGA studies Distribution: Kligerman et al.75 ; standard deviations of included DiGA studies |
| pDiGA_mild_moderate | 0.055 | Beta (0.006) | ||
| pDiGA_mild_severe | 0.022 | Beta (0.002) | ||
| pDiGA_mild_remis | 0.290 | Beta (0.069) | ||
| pDiGA_mild_death | 0.005 | Beta (0.001) | ||
| pDiGA_moderate_moderate | 0.763 | Calculated* | ||
| pDiGA_moderate_mild | 0.038 | Beta (0.012) | ||
| pDiGA_moderate_severe | 0.047 | Beta (0.005) | ||
| pDiGA_moderate_remis | 0.147 | Beta (0.015) | ||
| pDiGA_moderate_death | 0.005 | Beta (0.001) | ||
| pDiGA_severe_severe | 0.741 | Calculated* | ||
| pDiGA_severe_mild | 0.021 | Beta (0.002) | ||
| pDiGA_severe_moderate | 0.137 | Beta (0.031) | ||
| pDiGA_severe_remis | 0.094 | Beta (0.009) | ||
| pDiGA_severe_death | 0.006 | Beta (0.001) | ||
| Costs [in EUR] | ||||
| c_mild | Quarterly direct costs of an average patient in mild depression health state | 276.03 | Gamma (27.60) |
Pharmaceuticals: Bundesinstitut für Arzneimittel und Medizinprodukte96; Wissenschaftliches Institut der AOK97; IGES Institut98; Stahmeyer et al.78 Outpatient: Kassenärztliche Bundesvereinigung99; Stahmeyer et al.78; Expert judgement Inpatient: GKV Spitzenverband100; Statista101; Osterloh102 Overall: Bundesärztekammer et al.82; see Supplementary Table 3 for overview of included DiGA studies Distribution: Kligerman et al.75 |
| c_moderate | Quarterly direct costs of an average patient in moderate depression health state | 392.16 | Gamma (39.22) | |
| c_severe | Quarterly direct costs of an average patient in severe depression health state | 877.90 | Gamma (87.79) | |
| c_remis | Quarterly direct costs of an average patient in remission health state | 133.38 | Gamma (13.34) | |
| c_DiGA | Quarterly cost of an average patient using a depression DiGA | 232.74 | Gamma (20.76) | |
| c_health state_disc (_stage) | Discounted cost values per health state depending on current cycle | |||
| Utilities | ||||
| QALY_mild | Quarterly quality adjusted life years (QALY) of an average patient in mild depression health state | 0.140 | Beta (0.040) | Mohiuddin & Payne103 |
| QALY_moderate | Quarterly quality adjusted life years (QALY) of an average patient in moderate depression health state | 0.113 | Beta (0.045) | Mohiuddin & Payne103 |
| QALY_severe | Quarterly quality adjusted life years (QALY) of an average patient in severe depression health state | 0.063 | Beta (0.038) | Mohiuddin & Payne103 |
| QALY_remis | Quarterly quality adjusted life years (QALY) of an average patient in remission health state | 0.175 | Beta (0.040) |
Kolovos et al.104 Distribution: Revicki & Wood105 |
| QALY_health state_disc (_stage) | Discounted quality adjusted life years (QALY) per health state depending on current cycle | |||
*Transition probability in probabilistic sensitivity analysis is calculated according to the following formula: 1-sum of all remaining transition probabilities of respective health state, e.g. pwo_mild_mild=1-pwo_mild_moderate-pwo_mild_severe-pwo_mild_remis-pwo_mild_death.