Table 1 Checklist items for reporting modelling studies

STRUCTURE

Decision problem/objective

Is there a clear statement of the decision problem?

Is the objective of the evaluation specified and consistent with the stated decision problem?

Is the primary decision-maker specified?

Scope/perspective

Is the perspective of the model clearly stated?

Are the model inputs consistent with the stated perspective?

Are definitions of the variables in the model justified?

Has the scope of the model been stated and justified?

Are the outcomes of the model consistent with the perspective, scope and overall objective of the model?

Rationale for structure

Is the structure of the model consistent with a coherent theory of the health condition under evaluation?

Are the sources of data used to develop the structure of the model specified?

Are the causal relationships described by the model structure justified appropriately?

Structural assumptions

Are the structural assumptions clearly stated and justified?

Are the structural assumptions reasonable given the overall objective, perspective and scope of the model?

Strategies/comparators

Is there a clear definition of the options under evaluation?

Have all feasible and practical options been evaluated?

Is there justification for the exclusion of feasible options?

Model type

Is the chosen model type appropriate given the decision problem and specified causal relationships within the model?

Time horizon

Is the time horizon of the model sufficient to reflect all important differences between options?

Are the time horizon of the model, the duration of treatment and the duration of treatment effect described and justified?

Disease states/pathways

Do the disease states (state transition model) or the pathways (decision tree model) reflect the underlying biological process of the disease in question and the impact of the interventions?

Cycle length

Is the cycle length justified?

Parsimony

Is there indication that the structure of the model is as simple as possible and that any simplifications are justified?

DATA

Data identification

Are the data identification methods transparent and appropriate given the objectives of the model?

Are results reported in a way that allows the assessment of the appropriateness of each parameter input and each assumption in the target settings?

Where choices have been made between data sources, are these justified appropriately?

Where data from different sources are pooled, is this done in a way that the uncertainty relating to their precision and possible heterogeneity is adequately reflected?

Are the data used to populate the model relevant to the target audiences (i.e., decision-makers) and settings?

Has particular attention been paid to identifying data for the important parameters in the model?

Has the quality of the data been assessed appropriately?

Where expert opinion has been used, are the methods described and justified?

Data modelling

Is the data modelling methodology based on justifiable statistical and epidemiological techniques?

Baseline data

Is the choice of baseline data described and justified?

Are transition probabilities calculated appropriately?

Treatment effects

If relative treatment effects have been derived from trial data, have they been synthesized using appropriate techniques?

Have the methods and assumptions used to extrapolate short-term results to final outcomes been documented and justified? Have alternative assumptions been explored through sensitivity analysis?

Have assumptions regarding the continuing effect of treatment once treatment is complete been documented and justified? Have alternative assumptions been explored through sensitivity analysis?

Risk factors

Has evidence supporting the modeling of risk factors as having an additive or multiplicative effect on baseline probabilities or rates of disease incidence or mortality been presented?

Data incorporation

Have all data incorporated into the model been described and referenced in sufficient detail?

Has the use of mutually inconsistent data been justified (i.e., are assumptions and choices appropriate)?

Is the process of data incorporation transparent?

If data have been incorporated as distributions, has the choice of distribution for each parameter been described and justified?

If data have been incorporated as distributions, is it clear that second order uncertainty is reflected?

Assessment of uncertainty

Have the four principal types of uncertainty been addressed?

If not, has the omission of particular forms of uncertainty been justified?

Methodological

Have methodological uncertainties been addressed by running alternative versions of the model with different methodological assumptions?

Structural

Is there evidence that structural uncertainties have been addressed via sensitivity analysis?

Heterogeneity

Has heterogeneity been dealt with by running the model separately for different subgroups?

Parameter

Are the methods of assessment of parameter uncertainty appropriate?

If data are incorporated as point estimates, are the ranges used for sensitivity analysis stated clearly and justified?

Which sensitivity analyses were carried out?

CONSISTENCY

Internal consistency

Is there evidence that the mathematical logic of the model has been tested thoroughly before use?

External consistency

Are any counterintuitive results from the model explained and justified?

If the model has been calibrated against independent data, have any differences been explained and justified?

How was the model calibrated?

Calibration - description of source data

Calibration - description of search algorithm

Calibration - description of goodness-of-fit metric

Calibration - description of acceptance criteria

Calibration - description of stopping rule

Have the results of the model been compared with those of previous models and any differences in results explained?

VALIDITY

Output plausibility

Has evidence of face validity - evaluation by experts in the subject matter area for a wide range of input conditions and output variables, over varying time horizons – been presented?

Predictive validity

Was the validity of the model tested?

Is there a description of how the validity of the model was checked?

How was the validity quantified? (e.g., % explained)

COMPUTER IMPLEMENTATION

Is the software used in the study listed and its choice justified?

TRANSPARENCY

Is the model available to the reader?

Is a detailed document describing the calibration methods available?

Do the authors provide relevant appendices?

SPONSORSHIP

Is disclosure of relationship between study sponsor and performer of the study provided?