Table 1.

Checklist items for reporting modelling studies

Dimension of Quality	Reporting item	Philips	Unal	ISPOR	Nuijten	Stout	Drummond	Kopec
STRUCTURE
Decision problem/objective	Is there a clear statement of the decision problem?	x			x		x
	Is the objective of the evaluation specified and consistent with the stated decision problem?	x			x
	Is the primary decision-maker specified?	x					x
Scope/perspective	Is the perspective of the model clearly stated?	x		x	x
	Are the model inputs consistent with the stated perspective?	x					x
	Are definitions of the variables in the model justified?							x
	Has the scope of the model been stated and justified?	x						x
	Are the outcomes of the model consistent with the perspective, scope and overall objective of the model?	x
Rationale for structure	Is the structure of the model consistent with a coherent theory of the health condition under evaluation?	x		x				x
	Are the sources of data used to develop the structure of the model specified?	x
	Are the causal relationships described by the model structure justified appropriately?	x
Structural assumptions	Are the structural assumptions clearly stated and justified?	x	x	x	x
	Are the structural assumptions reasonable given the overall objective, perspective and scope of the model?	x
Strategies/comparators	Is there a clear definition of the options under evaluation?	x		x	x
	Have all feasible and practical options been evaluated?	x
	Is there justification for the exclusion of feasible options?	x
Model type	Is the chosen model type appropriate given the decision problem and specified causal relationships within the model?	x			x			x
Time horizon	Is the time horizon of the model sufficient to reflect all important differences between options?	x		x	x
	Are the time horizon of the model, the duration of treatment and the duration of treatment effect described and justified?	x
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?	x		x	x
Cycle length	Is the cycle length justified?	x		x	x
Parsimony	Is there indication that the structure of the model is as simple as possible and that any simplifications are justified?			x
DATA
Data identification	Are the data identification methods transparent and appropriate given the objectives of the model?	x		x	x
	Are results reported in a way that allows the assessment of the appropriateness of each parameter input and each assumption in the target settings?						x
	Where choices have been made between data sources, are these justified appropriately?	x					x	x
	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?						x
	Are the data used to populate the model relevant to the target audiences (i.e., decision-makers) and settings?						x
	Has particular attention been paid to identifying data for the important parameters in the model?	x
	Has the quality of the data been assessed appropriately?	x	x					x
	Where expert opinion has been used, are the methods described and justified?	x		x	x			x
Data modelling	Is the data modelling methodology based on justifiable statistical and epidemiological techniques?	x		x
Baseline data	Is the choice of baseline data described and justified?	x
	Are transition probabilities calculated appropriately?	x		x	x
Treatment effects	If relative treatment effects have been derived from trial data, have they been synthesized using appropriate techniques?	x		x
	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?	x		x	x
	Have assumptions regarding the continuing effect of treatment once treatment is complete been documented and justified? Have alternative assumptions been explored through sensitivity analysis?	x
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?			x
Data incorporation	Have all data incorporated into the model been described and referenced in sufficient detail?	x		x	x
	Has the use of mutually inconsistent data been justified (i.e., are assumptions and choices appropriate)?	x
	Is the process of data incorporation transparent?	x		x
	If data have been incorporated as distributions, has the choice of distribution for each parameter been described and justified?	x		x
	If data have been incorporated as distributions, is it clear that second order uncertainty is reflected?	x		x
Assessment of uncertainty	Have the four principal types of uncertainty been addressed?	x
	If not, has the omission of particular forms of uncertainty been justified?	x
Methodological	Have methodological uncertainties been addressed by running alternative versions of the model with different methodological assumptions?	x
Structural	Is there evidence that structural uncertainties have been addressed via sensitivity analysis?	x		x
Heterogeneity	Has heterogeneity been dealt with by running the model separately for different subgroups?	x		x
Parameter	Are the methods of assessment of parameter uncertainty appropriate?	x		x	x		x	x
	If data are incorporated as point estimates, are the ranges used for sensitivity analysis stated clearly and justified?	x	x
	Which sensitivity analyses were carried out?		x
CONSISTENCY
Internal consistency	Is there evidence that the mathematical logic of the model has been tested thoroughly before use?	x		x				x
External consistency	Are any counterintuitive results from the model explained and justified?	x		x	x
	If the model has been calibrated against independent data, have any differences been explained and justified?	x	x
	How was the model calibrated?		x
	Calibration - description of source data					x		x
	Calibration - description of search algorithm					x		x
	Calibration - description of goodness-of-fit metric					x		x
	Calibration - description of acceptance criteria					x		x
	Calibration - description of stopping rule					x		x
	Have the results of the model been compared with those of previous models and any differences in results explained?	x		x	x			x
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?							x
Predictive validity	Was the validity of the model tested?		x		x	x		x
	Is there a description of how the validity of the model was checked?		x			x
	How was the validity quantified? (e.g., % explained)		x
COMPUTER IMPLEMENTATION	Is the software used in the study listed and its choice justified?		x		x			x
TRANSPARENCY	Is the model available to the reader?		x
	Is a detailed document describing the calibration methods available?					x
	Do the authors provide relevant appendices?				x
SPONSORSHIP	Is disclosure of relationship between study sponsor and performer of the study provided?				x