IMS Accessible Portable Item Protocol (APIP) Overview

Version 1.0

Candidate Final
Version 1.0

Date Issued: 26 March 2012

Latest version: http://www.imsglobal.org/apip/

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Executive Summary

This document contains the technical specification overview of the Accessible Portable Item Protocol (APIP) Standard. The APIP Standard provides assessment programs and question item developers with a data model for standardizing the interchange file format for digital test items. When applied properly, the APIP standard accomplishes two important goals. First, the standard allows digital Tests and Items to be ported across APIP compliant test item banks. Second, it provides a test delivery interface with all the information and resources required to make a Test and an Item accessible for students with a variety of disabilities and special needs. In this version of the APIP Standard the focus is on:

a) Enabling the exchange of question Items and Tests;

b) Adopting, wherever possible, established learning technology interoperability standards and specifications, and only extending these when required;

c) Ensuring that the solution can be readily expanded, at a later date, to support the exchange of other related assessment information;

d) Ensuring the solution can be combined with other IMS Global Learning Consortium (IMS) and non-IMS specifications to support new functionality e.g. the reporting of assessment scores and outcomes;

e) Ensuring that further profiling can be undertaken to tailor the approach to meet the needs of specific State assessment activities without compromising the baseline interoperability requirement and capability;

f) Enabling vendors to adopt the solution without constraining their ability to create market-differentiated products and services.

The APIP standard builds on the IMS Question and Test Interoperability (QTI) v2.1 specification; this in turn makes use of the IMS Content Packaging (CP) v1.2 specification. The APIP Standard expands the QTI model into a comprehensive framework that encompasses the requirements for creating accessible tests. The IMS Access For All Personal Needs & Preferences (AfA PNP) v2.0 specification is also adopted as the basis for supplying the user preferences when using an APIP-enabled system. It is these accessibility preferences that are used by an assessment system to tailor, in real-time, the presentation of the question items to fit the accessibility needs of the user.

A conformance program and online validation tool have also been developed and deployed. Organizations that wish to achieve content or system compliance are encouraged to contact IMS. The APIP Working Group welcomes feedback and advice from the community for the improvement of this proposed standard.

1. Introduction

1.1. The Context for APIP

The Accessible Portable Item Protocol (APIP) Standard provides assessment programs and item developers with a tool for standardizing the file format of digital test items. When applied properly, the APIP standard accomplishes two important goals. First, the standard allows digital test items to be ported across APIP compliant test item banks. Second, it provides a test delivery interface with all the information and resources required to make a test item accessible for students with a variety of disabilities and special needs.

The APIP standard builds on the IMS Question and Test Interoperability (QTI) and the Access for All Personal Needs and Preferences (AfA PNP) specifications. QTI is based on an Item and Test model that allows item developers to specify a variety of information about a test item and to links these to create an assessment Test. The APIP standard expands the QTI model into a comprehensive content accessibility framework for Items and Tests. The AfA PNP defines the data model for the exchange of preferences for the use of learning systems. Again, APIP has expanded this specification.

The concept of test accommodations has evolved rapidly over the past decade as a result of computer-based test delivery. Test accommodations have traditionally been defined as changes to test conditions made after a test was developed. Since changes were made post-hoc, concerns often surfaced about the extent to which changes affected the measure of the intended construct. In addition, when changes were made by local test administrators concerns were raised about the accuracy of the changes.

However, computer-based test delivery provides important opportunities to define appropriate changes to the presentation or administration of test content a priori and to standardize the provision of these changes across all examinees. In essence, this transition from post-hoc changes to a priori specifications has resulted in a shift from test accommodations to accessibility. This shift from accommodations to accessibility is reflected in many recent papers, reports, and, most importantly, guidelines for test accommodations developed by the Council of Chief State School Officers Assessing Student Education Students (CCSSO ASES) group. APIP is an attempt to evaluate the potential and capability of the specification-based approach.

1.2. The Core Use Cases

Version 1.0 of APIP is designed to support six core use cases, in addition to other minor ones:

· Importing of APIP Item(s) into an APIP compliant system/application/tool – the reading of an APIP interchange file (a form of ‘zip’ file) and the storage of the contents of that file in the system/application/tool;

· Exporting of APIP Item(s) from APIP compliant system/application/tool – the creation of an APIP interchange file that can be stored in an external repository and/or which can be imported into another APIP-compliant system/application/tool;

· Importing of APIP Test(s) into an APIP compliant system/application/tool – the reading of an APIP interchange file (a form of ‘zip’ file) and the storage of the contents of that file in the system/application/tool;

· Exporting of APIP Test(s) from APIP compliant system/application/tool – the creation of an APIP interchange file that can be stored in an external repository and/or which can be imported into another APIP-compliant system/application/tool;

· Loading of APIP Item(s) into an APIP run-time system/application/tool – real-time reading of a set of APIP Items (APIP defines only the interchange data model and not the exchange communications method);

· Obtaining APIP personal needs and preferences – reading a set of personal needs and preferences, from a Preferences System, so that a system/tool/application can be configured to render APIP Items in a manner suited to the personal needs and preferences of the user.

A broader set of use cases have been defined for APIP [APIP, 12a] so that later versions of APIP can be extended without causing incompatibilities with version 1 implementations.

1.3. The APIP Technical Documentation Set

The technical specification work has involved the development of extensions to the base IMS specifications and profiling of several IMS and non-IMS specifications. Profiling is the process by which, one or more specifications, are tailored and combined to provide a best practice solution. In the case of APIP, profiling has been completed for the IMS QTIv2.1 [QTI, 06], IMS AfA PNPv2.0 [PNP, 09], IMS Content Packaging v1.2 [CP, 07], IMS AfA Digital Resource Description (DRD) [DRD, 09] and IMS Metadata v1.3. Profiling of the IEEE Learning Object Metadata (LOM) [LOM, 02] has also been undertaken.

The technical documentation set for APIP consists of six other documents and the set of XML Schema Description (XSD) files and examples. Namely:

a) Accessible Portable Item Protocol (APIP) Use Cases [APIP, 12a] – containing the set of use cases to be addressed in APIP v1.0 and later versions (this ensures that the v1.0 solution is set within a broader interoperability framework);

b) Accessible Portable Item Protocol (APIP) Technical Specification [APIP, 12b] – containing the detailed profiling of the various interoperability specifications and a description of how systems are expected to process the information contained within the APIP Item, APIP Test and AfA PNP data files. This document is relevant to organizations wishing to adopt the APIP;

c) Accessible Portable Item Protocol (APIP) Technical Specification of Features for QTIv2.1 [APIP, 12c] – containing the detailed description of the information model and XSD binding for the extensions to the IMS QTIv2.1 specification required by APIP. This document is relevant, in particular, to organizations wishing to implement the APIP and who require the detailed technical descriptions of the new features;

d) Accessible Portable Item Protocol (APIP) Technical Specification of Features for AfA PNP v2.0 [APIP, 12d] – containing the detailed description of the information model and XSD binding for the extensions to the IMS AfA PNP v2.0 specification required by APIP. This document is relevant, in particular, to organizations wishing to implement the APIP and who require the detailed technical descriptions of the new features;

e) Accessible Portable Item Protocol (APIP) Best Practice & Implementation Guide [APIP, 12e] – containing a number of annotated examples of the data files exchanged by APIP compliant systems for the import/export of APIP Items and access to the APIP preferences. These examples demonstrate how the core use-cases are supported by the technical solution. This document is relevant to anyone wishing to understand how the APIP can be used;

f) Accessible Portable Item Protocol (APIP) Conformance & Certification [APIP, 12f] – containing the conformance specification for APIP v1.0. This also describes how an APIP instance and an APIP application/tool/system must comply to achieve the various APIP conformance certification marks;

g) Accessible Portable Item Protocol (APIP) Terms and Definitions [APIP, 12g] – containing the terms and definitions, and other useful information that is required to provide a full context for the APIP;

h) XSD files – these are the control validation files used by applications to confirm that the data instance files being exchanged by APIP compliant systems are syntactically correct;

i) Annotated examples – the set of example instance files that are described in the best practices examples document [APIP, 12h].

1.4. Feedback

This version of the document is Candidate Final, meaning the technical solution described in the specification is as definitive as possible in the absence of numerous systems and content that have implemented the specification and achieved official conformance. IMS strongly encourages its members and the community in general to continue/begin developing to the specification now. When a sufficient number of systems have proven the solution works through successful conformance achievement, the Candidate Final specification will be submitted to IMS members for Final approval. IMS expects only minor refinements based on implementation experience during this Candidate Final period.

Revisions to the APIP specification will be posted here: http://www.imsglobal.org/APIP/
To join the IMS developer and conformance certification community focused on APIP and QTI v2.1 please visit the IMS QTI2/APIP Alliance online here: http://imsglobal.org/apip/alliance.html
Public contributions, comments and questions can be posted here: http://www.imsglobal.org/community/forum/categories.cfm?catid=110

2. The Technical Approach

The technical approach has combined a traditional use-case driven requirements consideration with a priori knowledge that the solution will be based upon a number of IMS specifications. Furthermore, the approach is a reflection of the extensive IMS experience in creating learning technology interoperability solutions based upon the profiling of the IMS specifications.

2.1. Architectural Model

The architectural framework for the use of the APIP v1.0 is shown in Figure 2.1. The APIP is used to support four types of data interchange:

· Repository to repository exchange – interactions between digital repositories that are configured to make APIP compliant data available;

· Repository to content tool exchange – interactions between digital repositories and the tools that make the APIP data available to users such as content authors, learners, etc;

· Repository to assessment system – real-time provision of APIP Items from a digital repository to assessment systems;

· Preferences server to content tool exchange – interactions between content tools, such as an assessment system, and a preferences server that makes personal profile information available to other systems.

Figure 2.1 The APIP v1.0 architectural model.

2.2. Content Accessibility Model

The APIP content accessibility framework, as shown in Figure 2.2, is comprised of two information models to allow Items to be ported across Item Banks and which allow test delivery engines to tailor the presentation of Items to meet the access needs of each individual examinee.

Figure 2.2 The APIP content accessibility model.

The first information model focuses on Examinee Access Information. During test delivery, the Examinee Access Information model performs two functions. First, it provides information that allows a test delivery engine to activate specific tools that tailor the presentation of item content to the examinee. These embedded access definitions may include features such as magnification, alternate contrast, , auditory calming, breaks and answer masking. Second, it provides information that specifies which accessibility information embedded within the item model is pertinent to the examinee. A variety of types of access information can be placed within an item, including specifications for how an item is to be presented in auditory, Braille, signed, or tactile forms. In addition, the item information model allows an item developer to point to alternate versions of the item that are presented in an alternate language (e.g. Spanish) or in simplified English.

As depicted in Figure 2.2, the APIP item model has five components:

· Item Information – this is the metadata that accompanies the Item. This could include information about versioning, subject domain, relevant curriculum standard learning objectives addressed, etc.

· Content Information – information about the contents of the item that are to be presented to an examinee assuming no access needs have been defined for that user;

· Companion Material – content props that provide key information to be used when answering an Item e.g. a calculator, protractor, etc.

· Accessibility Information – the alternative content to be used to render the content in its described accessibility forms e.g. read aloud, Braille, sign language, etc.

· Inclusion Order – the rendering order of the content to be presented to the user undertaking the assessment. The actual order is determined by the user’s accessibility preferences and the range of alternative rendering options created for the Item.

2.3. Content Assessment Model

The APIP Items and Tests are encoded in the IMS QTI format: this uses the Extensible Mark-up Language (XML) and is commonly termed QTI-XML. In fact, the encoding also makes use of the IMS Content Packaging format. A schematic representation of the APIP content assessment model is shown in Figure 2.3. An APIP Item consists of a set of related QTI ‘assessmentItems’ that reflect the alternative versions of the default instance. Each of these ‘assessmentItems’ is contained within its own QTI XML instance file. The QTI XML instances also contain the Companion Materials, Inclusion Order and Accessibility Information, i.e., these are inserted at extension points inside the original IMS QTI XML structure. An APIP Item also consists of the set of asset files (an asset is a file that contains a digital resource to be used in rendering the APIP Item, e.g., an image file, an audio recording, web pages, etc.) and the metadata that is used to describe the APIP Item and to help in searching for, and identifying, APIP Items that conform to specific properties. A similar approach is taken for constructing the APIP Tests, i.e., QTI-XML profiles are used to create APIP equivalent forms of ‘assessmentSections’ and ‘assessmentTests’. Each test and section is supplied in its own XML instance file. An ‘assessmentTest’ contains the set of identifiers for the associated ‘assessmentSections’ and each ‘assessmentSection’ points to the associated ‘assessmentItems’.

Figure 2.3 The APIP content assessment model.

An IMS Content Package (CP) is used to collate all of this information and to structure it in a convenient exchange format (once the content package has been constructed it is exchanged as a zip file). Within a content package the manifest file (always termed the ‘imsmanifest.xml’) is used to identify the set of files and their relationships, e.g., order of presentation, etc. Each APIP item, section and test consists of a set of resources within a content package (so an ‘assessmentItem’ XML file is one such resource as is each asset). Furthermore, the metadata is linked to a resource (this means that a repository which does not have access to, or cannot interpret, the actual XML and assets can still obtain a catalogue of the contents and properties of the contained APIP Items, Sections and Tests).

It is recommended that all of the ‘assessmentItem’, ‘assessmentSection’ and ‘assessmentTest’ files be placed into a single directory for items, sections and tests respectively, within the content package and within that directory each APIP Item, Section and Test is assigned its own sub-directory to contain the XML instances and the associated assets[1]. All of the common assets should be placed in a separate resources directory and finally any control files (such as the validation XSDs) be placed in a third separate directory. The final recommendation is the inclusion of a mime-type file that a system can access to identify APIP Item compliant zip files.

2.4. Accessibility Preferences

The accessibility preferences are contained within their own AfA PNP XML instance file. This is a file that conforms to the format defined by the AfA PNP v2.0 specification plus the extensions that have been added by APIP. The manner in which this data file is obtained by an APIP compliant system is outside the scope of APIP, i.e., this is implementation dependent.

2.5. Specification Adoption and New Development

The technical specification work that has been undertaken to realize the APIP is:

· Profiling of the IMS QTI v2.1 specification to meet the specific needs of the APIP (further input is required from the community to ensure that this is fit for purpose). Separate QTI Metadata, QTI Item QTI Section and QTI Test profiles have been developed;

· Profiling of the IMS CP v1.2 specification to meet the specific needs of the APIP;

· Profiling of the IMS AfA PNP v2.0 specification to meet the specific needs of the APIP;

· Profiling of the IMS AfA DRD v2.0 specification to meet the specific needs of the APIP metadata and integration with the APIP profile of the IMS Content Packaging specification;

· Profiling of the IEEE LOM to meet the specific needs of the APIP and integration with the APIP profile of the IMS Content Packaging specification (further input is required from the community to ensure that this is fit for purpose);

· Creation of the APIP extension features of the IMS QTI v2.1 specification and reconciliation with the APIP profile of QTI (feedback from the community will identify amendments);

· Creation of the APIP extension features to the IMS AfA PNP v2.0 and reconciliation with the APIP profile of QTI (feedback from the community will identify amendments).

3. Adopting APIP

3.1. The Technical Implications

APIP is concerned with interoperability of information. It does not define how data is to be stored and processed within an end system, e.g., assessment authoring tool, etc. So, from the perspective of APIP Item(s) and Test(s) it is about exchanging them in the form of an APIP Interchange File, i.e., a zip file. Systems, tools and applications are not prevented from importing and/or exporting the same information in other formats. Furthermore, it is not a requirement, or even an expectation, that the APIP format is assumed as the internal formats used by a system. A conformance program for APIP is also available. This address compliance in terms of: the APIP interchange files and the systems that exchange these files; the APIP personal needs and preferences files and the systems that use them. Organizations wishing to achieve conformance for their APIP products should contact IMS. Details about conformance are explained in the Conformance and Certification document [APIP, 12f] and support for implementers is available on the IMS website: http://www.imsglobal.org/developers/apipalliance/index.cfm

3.2. The Benefits

The benefits of the approach undertaken for the development of the APIP are:

a) The adoption, wherever possible, of established learning technology interoperability standards and specifications, and only extending these when required, reduces the risk of encountering unknown implementation difficulties;

b) Ensures that the solution can be readily expanded, at a later date, to support the exchange of tests and related assessment information, e.g., curriculum coverage metadata. This avoids wasting implementation effort and maximizes return on investment;

c) Ensures the solution can be combined with other IMS and non-IMS specifications (including SIF) to support new functionality, e.g., the reporting of assessment scores and outcomes. Again this minimizes implementation effort and risk;

d) Ensures that further profiling can be undertaken to tailor the approach to meet the needs of specific State assessment activities without compromising the baseline interoperability requirement and capability;

e) Enables vendors to adopt the solution without constraining their ability to create market-differentiated products and services. One objective is to ensure that vendors can still differentiate their commercial offerings without depending on proprietary content formats;

f) Provides an ‘open’ approach that is developed in conjunction with the end user and vendor communities. This joint ownership is essential in achieving a useful and used solution;

g) Takes advantage of the extensive experience that IMS has of developing and support, for the adoption, of learning interoperability specifications. This includes a number of special specification development tools and access to a conformance test capability for all content package based solutions (as is the case for APIP).

Appendix A – Related Documents

[APIP, 12a] Accessible Portable Item Protocol (APIP) v1.0 Use Cases, Candidate Final Release, G.Driscoll, T.Hoffmann, W.Ostler, M.Russell, M.McKell and C.Smythe, IMS Global Learning Consortium Inc., March 2012.

[APIP, 12b] Accessible Portable Item Protocol (APIP) v1.0 Technical Specification, Candidate Final Release, G.Driscoll, T.Hoffmann, W.Ostler, M.Russell, M.McKell and C.Smythe, IMS Global Learning Consortium Inc., March 2012.

[APIP, 12c] Accessible Portable Item Protocol (APIP) v1.0 Technical Specification of QTIv2.1 Features, Candidate Final Release, G.Driscoll, T.Hoffmann, W.Ostler, M.Russell, M.McKell and C.Smythe, IMS Global Learning Consortium Inc., March 2012.

[APIP, 12d] Accessible Portable Item Protocol (APIP) v1.0 Technical Specification of AfA PNP v2.0 Features, Candidate Final Release, G.Driscoll, T.Hoffmann, W.Ostler, M.Russell, M.McKell and C.Smythe, IMS Global Learning Consortium Inc., March 2012.

[APIP, 12e] Accessible Portable Item Protocol (APIP) v1.0 Best Practices and Implementation Guide, Candidate Final Release, G.Driscoll, T.Hoffmann, W.Ostler, M.Russell, M.McKell and C.Smythe, IMS Global Learning Consortium Inc., March 2012.

[APIP, 12f] Accessible Portable Item Protocol (APIP) v1.0 Conformance and Compliance, Candidate Final Release, G.Driscoll, T.Hoffmann, W.Ostler, M.Russell, M.McKell and C.Smythe, IMS Global Learning Consortium Inc., March 2012.

[APIP, 12g] Accessible Portable Item Protocol (APIP) v1.0 Terms and Definitions, Candidate Final Release, G.Driscoll, T.Hoffmann, W.Ostler, M.Russell, M.McKell and C.Smythe, IMS Global Learning Consortium Inc., March 2012.

[CP, 07] IMS Content Packaging Information Model v1.2, W.Kraan, J.Posten-Day, N.Ward, N.Boyd and C.Smythe, CM/DN Revision 2, IMS Global Inc., March 2007.

[DRD, 09] IMS Access For All Digital Resource Description Information Model v2.0, R.Schwerdtfeger, M.Rothberg and C.Smythe, Final Release, IMS Global Inc., October 2009.

[LOM, 02] IEEE 1484.12.1–2002 Standard for Learning Object Metadata, The Institute of Electrical and Electronics Engineers Inc., 2002. ISBN:0-7381-3297-7.

[PNP, 10] IMS Access For All Personal Needs & Preferences Information Model v2.0, R.Schwerdtfeger, M.Rothberg and C.Smythe, Final Release, IMS Global Inc., April 2010.

[QTI, 06] IMS Question & Test Interoperability Assessment Test, Section and Item Information Model v2.1, S.Lay and P.Gorissen, Public Draft Revision 2, IMS Global Inc., June 2006.

About this Document

Title: IMS Accessible Portable Item Protocol (APIP) Overview

Editors: Colin Smythe (IMS Global) and Mark McKell (IMS Global)

Co-chairs: Gary Driscoll ETS (USA), Thomas Hoffmann (Measured Progress) and Wayne Ostler (Pearson)

Version: 1.0

Version Date: 26 March 2012

Release: Draft 1.0

Status: Candidate Final Release

Summary: The aim of the APIP Project is to use well established e-learning interoperability standards to enable the exchange of accessible assessment content between computer-based assessment systems, tools and applications. Users of systems, tools and applications that adopt the APIP are able to use their accessible assessment content on a wide range of systems.

Revision Information: First release.

Purpose: This document is made available for adoption by the public community at large.

Document Location: http://www.imsglobal.org/apip/

List of Contributors

The following individuals contributed to the development of this document:

Rob Abel IMS Global (USA)	Devin Loftis McGraw-Hill/CTB (USA)
Gary Driscoll ETS (USA)	Mark McKell IMS Global (USA)
Eric Hansen ETS (USA)	Wayne Ostler Pearson (USA)
Casey Hill ETS (USA)	Zack Pierce Measured Progress (USA)
Regina Hoag ETS (USA)	Mike Russell Measured Progress (USA)
Thomas Hoffmann Measured Progress (USA)	Colin Smythe IMS Global (UK)

Revision History

Version No.	Release Date	Comments
Candidate Final v1.0	26 March 2012	The first formal release of the Candidate Final Release version of this document.

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Please refer to Document Name: IMS APIP Overview v1.0
Candidate Final Release v1.0

Date: 26 March 2012

[1] This is an initial best practice. These recommendations may be changed once there is sufficient adoption feedback to determine whether or not this approach of separation is useful.