Measurement
The MEASUREMENT table contains records of Measurement, i.e. structured values (numerical or categorical) obtained about a Person or Person’s sample. It contains results of Measurements such as laboratory tests, vital signs, quantitative findings from pathology reports, etc.
Field |
Required |
Type |
FK Table |
Description |
measurement_id |
Yes |
bigint |
|
A unique identifier for each Measurement. |
person_id |
Yes |
bigint |
PERSON |
A foreign key identifier to the Person about whom the measurement was recorded. The demographic details of that Person are stored in the PERSON table. |
measurement_concept_id |
Yes |
bigint |
CONCEPT |
A foreign key to the standard measurement concept identifier in the Standardized Vocabularies. |
measurement_date |
Yes |
date |
|
The UTC date of the Measurement. |
measurement_datetime |
No |
datetime |
|
The result / EPR entry UTC datetime of the Measurement. |
measurement_time |
No |
varchar(10) |
|
Not used. |
measurement_type_concept_id |
No |
bigint |
CONCEPT |
Not used. |
operator_concept_id |
Yes if value_as_number
is used |
bigint |
CONCEPT |
A foreign key identifier to the predefined Concept in the Standardized Vocabularies reflecting the mathematical operator that is applied to the value_as_number
. See Operator below. |
value_as_number |
No |
numeric/float |
|
A Measurement result where the result is expressed as a numeric value. |
value_as_concept_id |
No |
bigint |
CONCEPT |
A foreign key to a Measurement result represented as a Concept from the Standardized Vocabularies (e.g., positive/negative, present/absent, low/high, etc.). |
unit_concept_id |
No |
bigint |
CONCEPT |
A foreign key to a Standard Concept ID of Measurement Units in the Standardized Vocabularies. |
range_low |
No |
numeric/float |
|
The lower limit of the normal range of the Measurement. Assumed to be of the same unit of measure as the Measurement value. |
range_high |
No |
numeric/float |
|
The upper limit of the normal range of the Measurement. Assumed to be of the same unit of measure as the Measurement value. |
provider_id |
No |
bigint |
PROVIDER |
Not used. |
visit_occurrence_id |
No |
bigint |
VISIT_OCCURRENCE |
A foreign key to the Visit Occurrence during which the Measurement was recorded. |
visit_detail_id |
No |
bigint |
VISIT_DETAIL |
A foreign key to the Visit Detail during which the Measurement was recorded. |
measurement_source_value |
No |
varchar(100) |
|
Not used. |
measurement_source_concept_id |
No |
bigint |
CONCEPT |
Not used. |
unit_source_value |
No |
varchar(100) |
|
Not used. |
value_source_value |
No |
varchar(100) |
|
Not used. |
last_updated_datetime |
Yes |
datetime |
|
Initially this is the time the row was written to OMOP. If the row is subsequently updated, it then becomes the most recent update time. |
deleted_datetime |
No |
datetime |
|
NULL
initially. Set to the time when the row was marked for deletion. A value in this column sent to the central data source will result in this row being deleted (by person_id
) from the combined dataset. Deletions only need to be sent once. |
Conventions
- Measurements differ from Observations in that their results are either categorical coded values or numbers.
Observations are anything else.
- Measurements are stored as attribute-value pairs, with the attribute as the Measurement Concept and the value representing the result.
The value can be a Concept (stored in
value_as_concept
), or a numerical value (value_as_number
) with a Unit (unit_concept_id
).
- Valid Concepts for the
value_as_concept
field belong to the “Meas Value” domain.
- If reference ranges for upper and lower limits of normal are provided (typically by a laboratory) these are stored in the
range_high
and range_low
fields.
Ranges have the same unit as the value_as_number
.
- The Visit during which the Measurement was made is recorded through a reference to the VISIT_OCCURRENCE table.
This information is optional.
Standard Mappings
Operator
Code |
Name |
4171756 |
< |
4171754 |
<= |
4172703 |
= |
4172704 |
> |
4171755 |
>= |