The papers listed below discuss a variety of technical topics of potential interest to NAADSM users and other disease models. New technical papers will be added as interests arise and as time allows.
For information about a particular technical topic, please contact a member of the NAADSM Development Team.
- Technical paper #1: Versioning, stability, verification, and validation of NAADSM (165 KB)
- This document describes the approaches used by the NAADSM Development Team to provide a versioned, stable, verified platform for epidemiologic simulation modeling. This document also describes ongoing efforts of the NAADSM Development Team and associated researchers to address the issue of model validation.
- Technical paper #2: Combining data from several sources to produce a single set of contact spread parameters for NAADSM (158 KB)
- NAADSM uses only a single set of parameters to define all forms of disease spread by indirect contact. In some cases, this may not be sufficient to construct a model with the desired level of detail. This paper describes an approach and software that can be used to combine data regarding multiple, independent sources of indirect contact into one set of parameters suitable for use in NAADSM.
- Technical paper #3: Developing tests for verification of the NAADSM modeling framework (160 KB)
- One of the key characteristics of NAADSM is that it has been verified against the model specification. Part of this verification is the included unit and system test suite. It is crucial that this test suite is kept up to date. This document is intended to help developers as they create new tests to be incorporated into the automated suite.
- Technical paper #4: Understanding vaccination queues in NAADSM 3 and NAADSM 4 (85 KB)
- Vaccination is one of several disease control measures that can be simulated in NAADSM. One of the parameters that influences the effectiveness of a vaccination strategy is the capacity to actually carry out vaccination activities. This technical paper describes and compares the approaches used by NAADSM 3 (including all releases of NAADSM 3.0, 3.1, and 3.2) and the upcoming NAADSM 4 for queuing units to be vaccinated. This paper is highly recommended for users interested in using NAADSM to evaluate resource needs for disease control by vaccination.
- Technical paper #5: Developing unit-level disease state and within-unit prevalence parameters for NAADSM (168 KB)
- This report describes how a model of within-unit (i.e., within-flock or within-herd) disease dynamics can be used to develop parameters for NAADSM, a model of between-unit spread and control of disease. In NAADSM, disease state transitions are represented at the unit level. We have developed a separate model of within-unit disease spread, called WH, which represents the dynamics of disease spread, progression, and immunity at the level of individual animals within a homogeneously mixing herd. Outcomes produced by WH can be used to develop several key parameters for NAADSM, including unit-level disease state durations and levels of within-unit prevalence of disease.
Technical paper #6: Calculating probabilities of local-area and airborne disease spread in NAADSM 4 (232 KB)
Microsoft Excel spread sheet for technical paper #6 (58 KB)
- This report describes the calculations used in NAADSM 4 for producing the daily probability of local-area and airborne transmission between an infectious source and susceptible recipient unit. These calculations have been implemented in a Microsoft Excel spreadsheet, useful for visualizing these probabilities as they will be applied in NAADSM 4-based models.