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. 2020 Nov 2;20(12):1–134.

Table 8:

Scenario Analyses

Parameter Used
Scenario Reference Case Scenario Analyses
1. Cost perspective Public payer perspective (Ontario Ministry of Health) Societal perspective
See Table 7 for more details
2. Cost perspective: remote outpatient clinic, societal perspective Switching out of outpatient clinic NB-UVB:

  • First year: 15%

  • Each subsequent year: 10%


Public payer perspective		 Larger proportion switching out of outpatient clinic NB-UVB:

  • 20% per year


Societal perspective; higher travel-related costs and lost productivity

  • Travel: $87/mo (based on 60 km/appointment or 3x higher than reference case)

  • Parking and other miscellaneous costs (ex., meals): $37.5/mo (based on $15/appointment)

  • Lost productivity: $205/mo (based on 4 hr/appointment or 2x higher than reference case)
3. Number of treatments for outpatients 30 (assuming outpatients have no maintenance phototherapy) 51 (assuming 50% have no maintenance phototherapy, 50% have 1 maintenance treatment per week after initial 30 treatments)
4. Cost of home NB-UVB: payment model Purchased outright

  • Initial device cost: $3,912

  • Bulb replacement: $25/mo

 Rental-purchase

  • One-time shipping cost: $100

  • Monthly fee: $256/mo
5. Cost of home NB-UVB: device type 100% full-body panel devices

  • Initial device cost: $3,912

  • Bulb replacement: $25/mo

 Mixed devices (50% full-body panel, 20% small panel, 20% handheld, and 10% hand-foot units)

  • One-time device cost: $2,771

  • Bulb replacement: $17/mo
6. Cost of home NB-UVB device: cost-sharing 100% of cost of home NB-UVB device covered by the public payer (both purchase outright and rental purchase scenarios) 75% cost of home NB-UVB device covered by the public payer, applying to both purchase outright (scenario 6A) and rental purchase scenarios (scenario 6B)
Rationale: we assumed that if home NB-UVB is publicly funded, the funding structure may be similar to the Assistive Device Program,87 which offers 75% coverage to those 25–65 years of age who do not receive social assistance
7. Transition probabilities for home NB-UVB Home NB-UVB has slightly lower switching compared to outpatient clinic NB-UVB

  • First year: 10% (vs. outpatient clinic: 15%)

  • Each subsequent year: 7.5% (vs. outpatient clinic: 10%)

 Scenario 7A: home NB-UVB has worse adherence (higher switching probabilities) compared to outpatient clinic NB-UVB

  • First year: 20%

  • Each subsequent year: 15%


Scenario 7B: home NB-UVB has equal adherence (switching probabilities) as outpatient clinic NB-UVB

  • First year: 15%

  • Each subsequent year: 10%


Scenario 7C: home NB-UVB has better adherence (lower switching probabilities) compared to outpatient clinic NB-UVB

  • First year: 7.5%

  • Each subsequent year: 5%
8. Cost of topical therapy Betamethasone-17-valerate 0.05%

  • Monthly cost: $51.33

 More expensive topical therapy (e.g., calcipotriol-betamethasone proprionate)

  • Monthly cost: $430
9. Treatment pathway 100% of those switching out of phototherapy would switch into topical therapy Those switching out of phototherapy would switch to systemic non-biologic (16%), biologic (14%), and topical therapy (70%)
For other clinical, utility and cost parameters, see Appendix 6A for more detail.
10. Utilities of home and outpatient clinic NB-UVB Utilities directly reported in the PLUTO trial, measured using EQ-5D Based on PASI scores reported in the PLUTO trial, utilities were derived using corresponding PASI utilities. See Appendix 6B for more detail.
11. Time horizon 10 years 5 years, 15 years
12. Discounting 1.5% 0%; 3%

Abbreviations: EQ-5D, EuroQol-five dimensions; NB-UVB, narrowband ultraviolet B phototherapy; PASI, Psoriasis Area and Severity Index.