The NAADSM model specification

The NAADSM model specification is intended to be a plain-language description of the conceptual model implemented in NAADSM. Its purposes are to facilitate agreement among current team members on details of the model, to provide a basis for functional testing, and to provide future team members and other users with a complete but accessible description of the model.

For historical reasons, NAADSM version numbers start at 3.0.0. This scheme reflects continuity with SpreadModel¹, the conceptual model on which NAADSM was originally based. Version numbers for the NAADSM specification document start at 1.0.0: the first version of the NAADSM specification document was written for NAADSM 3.0.0. For a more thorough description of NAADSM version numbers, please see NAADSM versioning.

Development of NAADSM is on-going, and new versions of the program are written to conform to updated versions of the model specification. The model specification is updated via Requests for Comment (RFCs). RFCs provide detailed descriptions of proposed changes to the model specification. RFCs should include justification for the proposed changes and any supporting documents, e.g., manuscripts from the scientific literature. Changes proposed in RFCs are discussed and may be revised by the NAADSM Development Team. An RFC that is accepted after evaluation is merged into a new version of the model specification.

The following tables show the relationships between versions of the NAADSM application and the model specification, and list RFCs that have been incorporated in the specification document.

Specification 1.2 (for NAADSM 3.2)

This version of NAADSM will allow tracing back from detected units. NAADSM 3.2 will be backward compatible with previous versions: scenarios developed for NAADSM 3.0 or 3.1 will run in NAADSM 3.2 without modification.

Specification version 1.2		NAADSM version 3.2
	Latest revision:  Version 1.2.0 (11 Jun 2009)		Latest release: (Not yet released)
	Specification revision history [Show/Hide]

Version 1.2.1 (Not yet released) [RFCs adopted]
	RFC-20070910NH	Conflict resolution rewording:This RFC proposes a re-write of the section regarding how potential conflicts and ambiguities in the model are resolved. These changes are proposed for NAADSM 3.2.
	RFC-20070514NH	New distance formula:This RFC proposes a change to the way distances are calculated in NAADSM. A cartographic projection is applied to to latitude/longitude data to simply the calculation of distances between units. These changes are proposed for NAADSM 3.2.
Version 1.2.0 (11 Jun 2009) [RFCs adopted]
	RFC-20090429ARb	Vaccination of detected, infected units:This RFC proposes a change to the way detected infected units are currently handled when vaccination is used as a disease control strategy. These changes are proposed for NAADSM 3.2.
	RFC-20071127NH	Trace in:This RFC proposes a trace-in feature and an ability to do traces that go more than one step. Trace-in is part of the minimum required response to foot-and-mouth disease in the EU directive on FMD. These changes are proposed for NAADSM 3.2.

Specification 1.1 (for NAADSM 3.1)

This version of NAADSM introduced the option to simulate zones for disease detection and control. NAADSM 3.1 is fully backward compatible with version 3.0: scenarios developed for NAADSM 3.0 will run in NAADSM 3.1 without modification.

Specification version 1.1		NAADSM version 3.1
	Latest revision:  Version 1.1.1 (18 Sep 2008)		Latest release: NAADSM 3.1.23 (10 Aug 2009)
	Older application releases for this specification [Show/Hide]
	3.1.22, 3.1.21, 3.1.20, 3.1.19, 3.1.18, 3.1.17, 3.1.16, 3.1.15
	Specification revision history [Show/Hide]

Version 1.1.1 (18 Sep 2008) [RFCs adopted]
	Minor clarifications and formatting changes made in preparation for publication on the the NAADSM website, http://www.naadsm.org.
Version 1.1.0 (29 May 2007) [RFCs adopted]
	RFC-20070426AR	Direct costs of surveillance in zones:This RFC describes the parameters and calculations needed to determine the costs associated with surveillance within zones.
	RFC-20051111NHb	Zones:This RFC proposes adding disease-control zones that modify movement and detection.

Specification 1.0 (for NAADSM 3.0)

NAADSM 3.0 was the first version developed and released by the international NAADSM Development Team. This version of the model is described by version 1.0 of the NAADSM specification as well as in a paper (Harvey et al. 2007) published in the journal Preventive Veterinary Medicine.

Note: The features of NAADSM 3.0 are a subset of those available in NAADSM 3.1. Scenarios developed for NAADSM 3.0 will run in NAADSM 3.1 without modification. Use of NAADSM 3.1 rather than NAADSM 3.0 is highly recommended.

Specification version 1.0		NAADSM version 3.0
	Latest revision:  Version 1.0.7 (24 Apr 2007)		Latest release: NAADSM 3.0.84 (20 Oct 2006)
	Older application releases for this specification [Show/Hide]
	3.0.83, 3.0.82, 3.0.81, 3.0.80, 3.0.79
	Specification revision history [Show/Hide]

Version 1.0.7 (24 Apr 2007) [RFCs adopted]
	Describes the optional use of fixed rates for direct and indirect contact.
Version 1.0.6 (6 Apr 2006) [RFCs adopted]
	RFC-20060202AR	Trace surveillance: The proposed changes document the behavior of the current version of the core model regarding the process of trace surveillance.
	RFC-20051222NH	Quarantine: This RFC proposes adding notes for clarification to the direct contact section about potential recipients that are quarantined, about distance limits for shipments, and about the conditions under which a shipment can be dropped.
Version 1.0.5 (25 Jan 2006) [RFCs adopted]
	RFC-20060103AR	Quarantine of units awaiting vaccination: This RFC changes behavior of the model so that units awaiting vaccination are not quarantined and may participate in direct contact with other units.
Version 1.0.4 (23 Dec 2005) [RFCs adopted]
	RFC-20051130NH	Detection diagram: This RFC proposes adding a figure to the detection section to clarify the calculations used for the probability of detection.
	RFC-20051208NH	Destruction parameters for individual production types:This RFC proposes to change the way ring destruction is described in the model description document.
	RFC-20051213AR	Cost accounting parameters:The proposed change describes the parameters needed to track direct costs associated with a disease outbreak.
Version 1.0.3 (2 Nov 2006) [RFCs adopted]
	RFC-20050922ARa	Clarification of language regarding destruction of traces: This RFC clarifies the description of destruction of units identified by tracing activities.
	RFC-20050922ARb	Change in destruction and vaccination priority: This RFC proposes that destruction always take precedence over vaccination when both actions are scheduled to occur on the same simulation day.
	RFC-20050922ARc	Initiation of a vaccination program: This RFC clarifies the events that must occur before any units are marked for vaccination.
	RFC-20050927ARa	Clarification of infection timing: The proposed change explicitly codifies the current behavior of the model regarding the timing of infection events.
	RFC-20050927ARb	Clarification of infection timing: The proposed change explicitly codifies the current behavior of the model regarding the timing of detection events.
	RFC-20050928AR	Vaccination parameters for individual production types: This RFC describes the approach to vaccination used in legacy versions of SpreadModel, and proposes that it should be implemented in the current version of the model.
Version 1.0.2 (19 Feb 2005) [RFCs adopted]
	Reconciles differences between "SpreadModel" and "SHARCSpread" implementations, as discussed in Guelph, Ontario, Canada, Feb. 14 - 15, 2005.
Version 1.0.1 (15 Sep 2004) [RFCs adopted]
	RFC-20040915NHa	Fix for airborne spread algorithm: This RFC proposes a fix to a formula used for airborne spread.
Version 1.0.0 (19 May 2004)