Table 4.
Characteristics of studies based on models
| Reference (Country) | Year of valuation | Study goal/intervention | Model type | Wound type | Perspective (horizon time) | Sources: costs (discount) | Sources: model inputs (discount) | CE/CB results | Limitations/needed improvements |
|---|---|---|---|---|---|---|---|---|---|
| Ortegon et al. (Netherlands) [36] | 1999 | Lifetime CE for international standards to prevent/treat DFUs (new Dutch guidelines) vs. current Dutch care | Risk-based Markov; 13 health states | DFUs | HC provider (lifetime) | Current care: 2 Netherlands studies; International standards : 1 USA study (3 %) |
Conventional vs. IGC: 1 UK study; Optimal foot care: 1 Swedish study; Utility weights: 1 Dutch study (discounted 3 %) |
10 % foot lesion reduction: $24,556/QALY; 90 % foot lesion reduction: $7,860/QALY |
Current care needs description; Details of cost components, unit costs, and resource utilization missing; some model validation/calibration |
| OPUMT (Canada) [37] | 2007? | Current care vs. 5 additional strategies (AF mattress with and without 4-h turning; nutritional supplementation; skin care for incontinence; RN staff time increase |
Risk-based Markov; 52 health states; (low/high risk) |
PUs | HC provider (lifetime) | MDS (Ontario); LTC homes survey in Ontario; several Canadian databases; multiple literature sources from Western countries |
MDS (Ontario); CIHI-DAD; multiple literature studies |
$Can6,328/QALY (mattress); $Can5,234/QALY (mattress + turning); $Can1.2 million/QALY (nutrition); $Can287k/QALY (skin care); $Can269k/QALY (nurses) |
Year of costs for many cost components not clear; missing some model calibration, face and internal validity; no cross-model validation performed |
| Padula et al. (USA) [38] | 2009 | Lifetime CE for using WOCN Society guidelines with financial investment to prevent PUs vs. standard of care | Semi-Markov; 7 health states | PUs | Societal (lifetime) | Multiple USA studies and databases (3 %) |
Multiple studies and databases; WOCN Society guidelines; Utility weights: multiple US studies and derivation from EQ-5D scores (discounting of 3 % assumed) |
−$1,463/QALY | Unit costs and quantities missing; model limited to single hospitalization in extrapolation to lifetime results; no model validation/calibration |
| Pham et al (Canada) [39] | 2009 | Lifetime CE for using 4 quality improvement strategies to prevent PUs vs. standard of care | Validated Markov model; 6 health states stratified by pt age, risk status, wound status, local or systemic infection, and care setting | PUs | HC provider (lifetime) | RAI-MDS (Ontario), CIHI OMHLTC, practice-based surveys and additional North American studies (3 %) |
RAI-MDS (Ontario), CIHI-DAD, practice-based surveys and additional North American studies Utility weights: 2 Canadian studies (3 %) |
Pressure redistribution: $Can−371/ QALD; Oral nutritional supplements (high-risk pts): $Can24,367/QALD Skin emollients (high-risk pts): $Can218/QALD Foam cleansing (high-risk pts): $Can−895/QALD |
Missing some model calibration, face and internal validity; no cross-model validation performed |
| Barshes et al. (USA) [40] | 2009 | CE over 10 years for pts with CLI (typically Rutherford 5) using 5 different strategies vs. local wound care | Probabilistic Markov model; 6 health states with interventions/re-interventions | Primarily DFUs | Societal (10 years) | Survey (US medical centers; vascular surgery); outpatients: various studies (3.5 %) | Various studies (3.5 %) |
Bypass/endovasc revisions: $47,738/QALY Bypass/surgical revisions: $58,749/QALY Endovascular, bypass for failure: $102k/QALY Purely endovascular: $121k/ QALY Amputation: $100k/ −QALY |
Missing detailed unit costs and quantities; no model validation/calibration |
| Mathiesen et al. (Denmark) [41] | 2011 | CE over 1 year to prevent PUs in hospital settings comparing the Danish PUB strategy vs. standard care | Decision analytic, 7 health states | PUs | HC provider (unclear, <1 year) | Danish DRG system; Danish public healthcare system; expert opinion; survey (none) | Danish, Scandinavian, and UK studies; (none) | −€415/ averted PU (patient basis) | Missing some data identification and selection methods; Missing detailed unit costs and quantities and some important costs; no provision for multiple hospitalizations; decision analytical model probabilities may be unrealistic |
AF alternative foam, CB cost benefit, CE cost effectiveness, CIHI-DAD Canadian Institute of Health Information-Discharge Abstract Database, CLI critical limb ischemia, DFU diabetic foot ulcer, DRG diagnosis-related group, HC healthcare, IGC intensive glycemic control, LTC long-term care, MDS minimum data set, OMHLTC Ontario Ministry of Health and Long-Term Care, OPUMT Ontario Pressure Ulcer Model Team, pt(s) patient(s), PU pressure ulcer, PUB pressure ulcer bundle, QALD quality-adjusted life-day, QALY quality-adjusted life-year, RAI-MDS residence assessment instrument-minimum data set, RN registered nurse, WOCN wound ostomy continence nurse