CCTOS Common : Item root class
Version 8.1,
- Objectives:
- The idea
is that a medical entity of information make sense only when a set of
essential attributes are available together.
- These essential informations are necessary nearly
everywhere in healthcare projects. This is why there are defined
once in a common root class and made available for all subsequent
derived classes.
- Centralized management of the most common generic
properties.
- Summary:
- The common properties expected to become
necessary in most
other classes. The basic building bloc of any medical
information
containing overall required information, typically as:
- Item unique ID:
- Of course unique in the current database.
- In order to share information in the scope of
networks of databases, maybe also the unique identifaication of the
dababase itself.
- version:
- For legal and for the possibility looking back,
update should never be authorized, but only the addition of new
versions. This apply to nearly all informations in the
following
chapters.
- Normally only the latest version is presented by
default, but previous
version must remain available on request.
- This
is necessary for all kinds of objects in a
healthcare system, including identifications of patients, medical data,
knowledge,
activities in progress, etc..., because any kind of information may
sometimes need to be updated, keeping the previous version. For example
in case of:
- Correction of the spelling of a patient name, a
critical issue
for the reliability of patient records. Any information implying
a responsibility need to be traceable.
- Followup of the understanding of problems.
- Correction of the result of a lab test.
- The insurance status of a patient or simply his
address may change on a given date eg the first of January, but a
little later in January it must remain possible to send correct
invoices for services provided a few weeks earlier in December.
- Validity range:
- Begin of the validity of a version.
- Optional end of validity, by default assumed to be
"up to now".
- Time stamp:
- Responsible agent:
- In a shared environment, medical information is
usable as far as the reader can identify the author and and as far as
he trust him.
- Subject of care:
- Since a high percentage of all items are dealing with
patient data, it seems safe to repeat the patient identification
explicitely inside every item.
- In most cases the "subject of care" is a patient, but
it should remain possible to support a few oher situations. For example
a lab must accept to perform a bacteriology test on a sample coming
from some surgical equipment or from an animal. Therefore it
should be perhaps necessary to indicate that the subject of care is a
patient.
- Type
of Item:
- The root class "item" will normally nrver be used
alone, but is inteded to be always extended with specific properties,
e.g. patient, doctor, medical data, prescription, knowledge, etc all
information assumed to have been created by a know author, at a known
time.
- The value of this field will be provided by the
derived class.
- Degree of certainty:
- Objective:
- To support medical practice, where the degree of
belief is a critical acpect of any information. Many decisions
have to be taken on basis of rought probabilities. For example:
- Seeing a possible risk of a serious disease but
yet without full confirmation, one may not wait to prescribe a
treatment, as far as non dangerous and not expensive.
- Remark about other objectives:
- Research projects dealing with classifications
for epidemiological statistics on large populations do not take account
of the degree of certainty of individual cases. An information
item is there simply reduced to true or false.
- Approach:
- The degree of certainty is here an evaluation about
the degree of belief of the author of the information. In a team
an other person could have a different degree of belief and require to
record an other instance of the item.
- Keep in mind that the overall goal of the project
is patient care and not pure academic discussion. Many thing are
no more than "very likely".
- A generic information, although not always
expressed. If nothing has
been said about the degree of certainty, the reader will usually assume
that the information has been considered as "obvious".
- The degree of certainty can appear nearly
everywhere:
- Mostly to qualify medical data, particularly
Health Issues, i.e. problems or diagnoses.
- But also in situations like uncertain
identification,
- .....
- A difficult question remains the representation of
the degree of belief in a standardized way, understood in the same way
by all the partners.
- Maybe a qualitative scale with about 10 possible
choices, from "certainly not", "not to exclude", "possible",
"probable", ... to "certainly well".
- Maybe an internal representation based on a score
from 0.0 to 1.0 . Altough subranges could be converted to the
above scale.
- Intensity:
- Like the degree of certainty, but here an other
dimension of qualification.
- Relevance, importantance ?
- Remark:
- The latest attributes are strongly dependent on the
evaluation of hte author. Diffenrent authors could have different
opinions.
- Integrity control:
- A kind of checksum could be added in other to verify
the integrity of the recod.
- etc...... (perhaps not yet fully defined at the current
stage)