Data Models

PIXI adds data types to XNAT that are specific to preclinical imaging research. The data models for these are described below. There is a new demographic data type for small animal subjects and a few new experiments that are specific to preclinical imaging research. See the Usage page for more information on how to use each of these data types.

Small Animal Subjects

The table below shows demographic information managed by PIXI. Rows marked in the column XNAT Core indicate demographic items that apply only to clinical subjects. Rows marked with PIXI indicate items that are unique to small animal subjects.

Field	Type	Core XNAT	PIXI
Date of Birth	Date	X
Year of Birth	Integer	X
Age	Integer	X
Gender	Enumerated	X
Handedness	Enumerated	X
Socioeconomic Status	Integer	X
Employment Status	Enumerated	X
Education Level	Integer (0-30)	X
Education Description	String	X
Race (multiple)	String	X
Ethnicity	String	X
Weight	Float + units	X
Height	Float + units	X
Gestational Age	Float	X
Post Menstrual Age	Float	X
Birth Weight	Float	X
Species	String		X
Strain	String		X
Source	String		X
Stock Number	String		X
Genetic Modifications	String		X
Genetic Modifications Summary	String		X
Date of Birth	Date		X
Sex	Enumerated		X
Litter	String		X
Strain Immune System Humanization Type	String		X
Date of Death	Date		X
Animal Endpoint	String		X

Experiments

The XNAT Experiment Data type documents a specific individual event in which primary data is obtained. XNAT maintains these just below the subject level, so a subject will have 0..N experiments. Experiments can be CT, MR or PET imaging sessions, but are not limited to imaging data. The baseline Experiment Data elements are listed in the table below. The PIXI experiment data types include these baseline elements and add the elements that are ascribed to the PIXI data type. Some elements used to link an Experiment to other data such as the XNAT Project or Visit are omitted for brevity.

Field	Type
ID (primary key)	String
Date	Date
Time	Time
Duration	Duration
Delay	Integer
Note	String
Investigator (Name, Institution, Dept…)	Composite
Validation (Date, Method, Status, …)	Composite
Acquisition Site	String
Version	Integer
Original	String
Protocol	String
Label	String

Caliper Measurements

An event in which a subject’s tumor volume is measured manually using a caliper measurement tool.

Field	Type
Length	Date
Width	Date
Unit	Date
Technician	Date
Weight	Date
Weight Unit	Date

Drug Therapy

An event in which a subject is administered a drug or medication.

Field	Type
Drug	String
Dose	Decimal
Dose Unit (e.g., mg)	String
Lot Number	String
Route (e.g.., oral)	String
Site	String
Technician	String
(Subject) Weight	Decimal
Weight Unit	Enumerated

Weight

An event in which a subject’s weight is obtained outside the context of an imaging experiment.

Field	Type
Weight	Decimal
Unit	Enumerated
Technician	String

Animal Husbandry

Record animal feeding and housing information over an interval during which conditions are relatively homogeneous.

Field	Type
Animal Feed	String
Feed Source	String
Feed Manufacturer	String
Feed Product Name	String
Feed Product Code	String
Feeding Method	String
Water Type	String
Water Deliver	String
Number of Animals In Same Housing Unit	Integer
Sex of Animals In Same Housing Unit	Decimal
Housing Humidity	Decimal

Cell Line

An event in which a cell line is injected into a small animal subject to create an animal model that can be used for preclinical research.

Field	Type
Source ID (Owned by the source, not XNAT)	String
Injection Site	String
Injection Type	String
Number of Cells Injected	Positive Int

Patient Derived Xenograft

An event in which human tumor tissue is engrafted into a small animal subject to create an animal model that can be used for preclinical research.

Field	Type
Source ID (Owned by the source, not XNAT)	String
Injection Site	String
Injection Type	String
Number of Cells Injected	Positive Int
Passage	String
Passage Method	String