Table 6 Risk of Bias Assessment for Modeling Studies
Criteria a | Criteria met (yes = 1, no/unclear = 0, NA = not applicable) | |||
|---|---|---|---|---|
Study (Author, Year) | ||||
Manissero, 2008 | Sutherland, 1989 | Brewer, 2001 | Gerberry, 2009 | |
Model Structure: | ||||
 Inputs and outputs relevant to decision-making | 1 | 1 | 1 | 1 |
 Structure consistent with the theory of the disease | 1 | 1 | 1 | 1 |
 Structure is simple but includes essential elements for vaccine policy decision-making (and any simplifications are justified) | 1 | 1 | 1 | 1 |
 Heterogeneity in the modelled population accounted for by stratifying by groups that have different outcome probabilities or costs | 1 | 0 | 1 | 1 |
 Time horizon of the model sufficient to detect important (and clinically meaningful) differences in long-term health and cost outcomes | 0 | 1 | 1 | 0 |
For Markov models / health state transition models: | ||||
 Health states appropriately defined, relevant subdivisions of health states included | NA | NA | 1 | 1 |
 Where relevant, transition probabilities take into account clinical history | NA | NA | 1 | 1 |
 Choice of cycle length justified | NA | NA | 0 | 0 |
Data Identification: | ||||
 Systematic reviews of the literature conducted on key model inputs | 0 | 0 | 1 | 0 |
 Ranges provided in base-case estimates of all input parameters for which sensitivity analyses were done | NA | NA | 1 | 1 |
 Data based on expert opinion, if used, are derived via formal methods, e.g. Delphi | NA | NA | NA | NA |
 Attempts to obtain new data prior to modeling have been considered | 1 | 1 | 1 | 1 |
Data Incorporation and Modeling: | ||||
 Modeling methods follow accepted methods of biostatistics and epidemiology | 1 | 1 | 1 | 1 |
 Included sensitivity analyses of key parameters | 0 | 0 | 1 | 1 |
 Model validation: | ||||
 Model subjected to internal testing through input of extreme values (or equal values for replication testing) | 1 | 0 | 0 | 1 |
 Calibration data, where available, should be from sources independent of those used to estimate inputs | 1 | 0 | 0 | 1 |
 Source code available for peer-review | 0 | 0 | 0 | 0 |
 Model based on the best evidence available at the time | 1 | 1 | 1 | 1 |