Adding context using the ACTIVITY_PROPERTIES file

The ACTIVITY_PROPERTY file provides a mechanism for attaching additional information to activity files. This is important for assays which generate values of a single result type, in which the values quoted must be qualified with another parameter that has been measured or set in the ACTIVITY file. Such additional information is often useful in assessing the mechanism behind the result, or the quality or reliability of the reported main value.

Typically, this file holds two kinds of data:

1. Independent variables in the assay which may have been systematically changed in order to assess their influence on the ACTIVITY VALUE (eg: Dose of test substance)

2. Calculated values relating to the ACTIVITY VALUE if considered particularly useful in assessing the quality of the ACTIVITY VALUE (eg the slope of an IC50 curve).

Records in the ACTIVITY and ACTIVITY_PROPERTY files must be linked using an activity ID (ACT_ID). In the ACTIVITY file, the ACT_ID must be unique for each record, although not all records need have a value since some activities may not have properties associated with them.

The ACT_ID must always be a positive integer, and only has meaning within the deposition so values can be reused in following depositions. In the ACTIVITY_PROPERTY file, each ACT_ID can occur multiple times, but must match an ACT_ID in the ACTIVITY file in the same deposition. All records in ACTIVITY_PROPERTY must contain an ACT_ID.

Sometimes, it is debatable as to whether a result such as slope, for example, should be considered a property (in ACTIVITY_PROPERTY) or a result type (in ACTIVITY) in its own right. There is no single rule to make this distinction, but ACTIVITY values should be the main variable measured in the assay, and ACTIVITY properties should be derived data or data specific to the single assay in question.

ACTIVITY_PROPERTIES.tsv

The ACTIVITY_PROPERTIES file should contain information that is necessary for interpretation of the ACTIVITY table data, for example the Hill slope of a curve. Raw results and other supporting information belongs in ACTIVITY_SUPP.

Each ACTIVITY can relate to multiple properties, via the ACT_ID field. Each ACTIVITY_PROPERTIES record can only link back to a single ACTIVITY record. Even if two ACTIVITY records have the same experimental conditions, they both need their own set of ACTIVITY_PROPERTIES records.

Can be used to supply additional activity information, for example the Hill slope of a curve. Should contain information that is necessary for interpretation of the ACTIVITY table data. Raw results and other supporting information belongs in ACTIVITY_SUPP.

• ACT_ID and TYPE are mandatory.

• A VALUE is numeric and requires an entry in the RELATION field. A TEXT_VALUE requires that RELATION is empty.

• TYPE describes the type of measurement.

• Depositors can set their own categories for TYPE, but should not use the same TYPE value for different sorts of data. For example PB_HILL_SLOPE and PB_R_SQUARED would be valid, but storing both Hill slope and R-Squared data as PB would not be, even if they had different UNITS or COMMENTS.

• Can contain dependent or independent variables. If RESULT_FLAG is set to 1, it shows the record is a dependent variable/result (e.g., slope) rather than an independent variable/parameter.

Header	Description	Existence	Data type
ACT_ID	The ACT_ID established by the depositor in the ACTIVITY file - a foreign key	Mandatory	Any integer up to a length of 11
TYPE	The type of property measurement. Must be unique within an ACT_ID Should be self-explanatory to external researchers	Mandatory	Any character up to a length of 250
RELATION	Symbol indicating relationship between the Type and the Value (permitted: '>','<','=','~','<=','>=','<<','>>')	Optional (Mandatory if a VALUE is given)	Any Relation symbol (=, >, <, ~, <=, >=, >>, <<) up to a length of 50
VALUE	The numerical value of the property measurement	Optional	Any number (including decimals, negatives and scientific notation (e.g. 3×10^2))
UNITS	The units of the property measurement	Optional	Any character up to a length of 100
TEXT_VALUE	The text value of non-numerical values	Optional	Any character up to a length of 1000
COMMENTS	A comment on the property. Can be used to further describe the TYPE, TEXT_VALUE or VALUE if needed	Optional	Any character up to a length of 4000
RESULT_FLAG	A flag to indicate, if set to 1, that this type is a dependent variable/result (e.g., slope) rather than an independent variable/parameter (0, the default).	Optional	0 or 1