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consistent naming convention throughout and a user friendly layout to efficiently

review the model.

The next domain is regarding clear listing of model assumptions, tables and
figures so as to facilitate the review process. The third domain pertains to model

functionality which includes checks for macros, ranges and look up values, check for

general error messages and any link to external sources. The fourth domain refers to

model inputs which includes listing of all inputs under one sheet, checking for

correctness of any conversion of parameters (ex: risk/ratios to probability), checking
for proportion sums and mutually exclusive parameters.

The next domain pertains to calculations done in the model. It includes correct

linking of different cells within as well as between sheets and the correct formulation

of processes like discounting, annualization, QALY calculations and others. The sixth

domain refers to checks pertaining to uncertainty analysis. It includes checking
appropriateness of ranges listed for all parameters, proper linking of tables and graphs

generated, functioning of macros, appropriateness of distributions assigned to

parameters and their sources and appropriate presentation of results of various

analyses. The seventh domain refers to the model output/summary. This section is

reviewed to ensure appropriate linking of summary estimates, comprehensive
description of results, appropriate linking and labelling of tables, figures and graphs.

The last domain talks about the validity of the model. This section seeks

information on whether the outputs of the model are in concurrence with the existing

scientific evidence available. For ex: Is the average life expectancy of the cohort in

concurrence with the existing evidence on the same, is the average predicted survival
from the model in concurrence with clinical evidence etc. This domain also talks about

the validity of model in terms of effectiveness of intervention. For ex: Is the reduction

in disease free episodes/ increase in average disease-free survival/ increase in average

progression free survival/ decrease in mortality from the model in concurrence with

the evidence from clinical effectiveness literature.

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