Title: Protocol Guideline Systems
1Protocol / Guideline Systems
- And other bits and pieces...
2Guideline Types - 3 axes
- 1) stage of care process
- screening
- diagnostic workup
- treatment
- 2) medical domain
- 3) intended application
- disease management
- critical path / clinical pathways
- clinical trial protocol
- appropriateness determination
3Guidelines Modes of Use
- Educational
- Interactive and passive / active for
- DSS support
- workflow support
- As Benchmark for QA applications
- NOTE guideline expression should be independent
of mode of use.
4Protocol Projects
- Prestige (NHS) Colin Gordon
- Eon (Stanford)
- Intermed (Stanford, MGH, Columbia DSG)
- Protégé
- HELP (Stanford)
- Prompt (ICRF) John Fox
- Prodigy (Stanford/Britain)
5Guideline Languages/ Models
- EON EON Project
- GLIF Intermed Project
- ASBRU Asgaard Project (1980s)
- Prestige Prestige Project
- Arden Syntax / MLMs
6Guideline Language 1 ASBRU
7ASBRU
- Language for specifying intentions.
- Good for temporal expressions.
- Abstraction functions included.
- Hierarchically structured plan.
- Modified Backus Naur form.
8ASBRU - Plan States
A set of mutually exclusive plan states describes
the actual status of the plan instance during
execution Transition conditions specifiy
criteria for transition between neighboring
plan-instance states. If a plan has been
activated, it can only be completed, suspended,
or aborted depending on the corresponding
criteria.
9ASBRU Plan (guideline) Types
- The plan body is a set of plans to be executed
- Several types of plans sequential,
concurrent, and cyclical. - Only one type of
plan is allowed in a single plan body. 1)
Sequential plan specifies a set of plans that are
executed in sequence for continuation, all plans
included have to be completed successfully. 2)
Concurrent plan can be executed in parallel or in
any order. 3) Cyclical plan (an EVERY clause)
includes a plan that can be repeated. Start and
end parameters specify a starting and ending time
point. Time base determines the time interval
over which the plan is repeated and the start
time, end time, and duration of the particular
plan instance in each cycle
10ASBRU - Preferences
Preferences Preferences bias or constrain the
selection of a plan to achieve a given goal and
express a kind of behavior of the plan. Examples
include (1) Strategy a general strategy for
dealing with the problem (e.g., aggressive,
normal) (2) Utility a set of utility measures
(e.g., minimize the cost or the patient
inconvenience) (3) Select-method a matching
heuristic for the applicability of the whole plan
(e.g., exact-fit) (4) Resources a
specification of prohibited or obligatory
resources (e.g., in certain cases of treatment of
a pulmonary infection, surgery is prohibited and
antibiotics must be used) (5) Start-conditions
an indication whether transition from a ready
generic plan to the activated state of an actual
plan instance is automatic (after applying the
filter and setup preconditions-see below) or
requires approval of the user.
11ASBRU- Condition Types
- (1) Filter-preconditions, which need to hold
initially if the plan is applicable, but should
not be achieved (e.g., patient is a pregnant
female), and are necessary for a possible state - (2) Setup-preconditions, which need to be
achieved to enable a plan to start (e.g., patent
had a glucose-tolerance test) and allow a
transition from a possible plan to a ready plan - (3) Suspend-conditions, which determine when a
started plan has to be suspended (e.g., blood
glucose has been high for four days) these are
informally the inverse of protection conditions
in the planning literature, which have to hold
during certain time periods. - (4) Abort-conditions, which determine when a
started, suspended, or restarted plan has to be
aborted (e.g., there is an insulin-indicator
condition the patient cannot be controlled by
diet) - (5) Complete-conditions, which determine when a
started or restarted plan has to be completed
successfully (e.g., delivery has been performed)
- (6) Reactivate conditions, which determine when a
suspended plan can be reactivated (e.g., blood
glucose level is back to normal or is only
slightly high)
12ASBRU - Intentions
Intentions - high-level goals at various levels
of the plan, an annotation specified by the
designer that supports tasks such as critiquing
and modification. (1) Intermediate state the
patient state(s) that should be maintained,
achieved, or avoided during the applicability of
the plan (e.g., weight gain levels are slightly
low to slightly high). (2) Intermediate action
the provider action(s) that should take place
during the execution of the plan (e.g., monitor
blood glucose once a day). (3) Overall state
pattern the overall pattern of patient states
that should hold after finishing the plan (e.g.,
patient had less than one high glucose value per
week). (4) Overall action pattern the overall
pattern of provider actions that should hold
after finishing the plan (e.g., patient had
visited dietitian regularly for at least three
months).
13ASBRU The problem of time...
The upper part of the figure presents the generic
annotation. The lower part shows a particular
example representing the time annotation which
means "starts 24 to 26 weeks after conception,
ends 32 to 34 weeks after the conception, and
lasts 5 to 8 weeks." REFERENCE reference
annotation, ESS earliest starting shift, LSS
latest starting shift, EFS earliest finishing
shift, LFS latest finishing shift, MinDu
minimal duration, MaxDu maximal duration
14Guideline Language 2 ARDEN
15ARDEN MLM Functional Components
- context (evoke slot) - when is this MLM
pertinent? - data storage, another MLM,
application - logic (logic slot) - set of medical criteria or
algorithm - concludes true or false - action (action slot) - executed when logic
concludes true - store message, send e-mail,
return value. - mapping (data slot) - terms in MLM must be mapped
to institution's local database.
logic
Message Alert Interpretation Screen
context
action
mapping
data
16ARDEN Syntax
ASCII file of slots grouped into categories
maintenance title ... filename ...
... library purpose ...
explanation ... ... knowledge type
... data ... ... end
logic if hematocrit is not number then
conclude false endif if hematocrit lt
previous_hct - 5 or hematocrit lt30 then
conclude True endif action write "The
patient's hematocrit (" hematocrit ") is low
or falling rapidly." end
17Guideline Language 3 EON
18EON
- Temporal language for query evaluation
- Flow chart control.
- Abstraction is part of model.
19Guideline Language 4 GLIF
- Guideline interchange format
20GLIF - CORBA interchange format
GLIF consists of a number of object class
definitions, each of which carries some data. A
guideline is made up of a collection of data
elements, or instances, that are structured
according to these class definitions. At the
highest level, each guideline is described by the
Guideline class, which is represented as follows
interface Guideline attribute string
name attribute sequence ltstringgt authors
attribute string intention attribute
Criterion eligibility_criteria attribute
sequence ltGuideline_Stepgt steps attribute
Guideline_Step first_step attribute sequence
ltSupplemental_Materialgt didactics
21GLIF - guideline steps
The guideline consists of a collection of steps,
arranged in a graph structure that may be
traversed according to the nature of a specific
case. A number of step types are defined for
capturing the nature of decision making and
actions that take place during the patient care
process. Each step contains a name and a list of
supporting didactic material. The generic
guideline step is defined as follows interface
Guideline_Step attribute string name
attribute sequence ltSupplemental_Materialgt
didactics
22GLIF - Action steps
Action steps are used to record the actions that
are actually performed during the patient care
process that is being modeled by the guideline.
Each action step contains an action
specification, optionally a sub-guideline, which
details the action at a finer level of
granularity, and a pointer to the next step in
the guideline, that is reached once the action
has been performed. interface
Action_StepGuideline_Step attribute
Action_Spec action attribute Guideline
subguideline attribute Guideline_Step
next_step
23GLIF - Patient Data
- Action may contain 0 or more patient data
elements values collected as result of action.
Patient data contain, for each data element - a data element name,
- type,
- an optional list of acceptable values,
- a measure of how recent a value must be to be
considered valid, and - a list of supporting didactic materials.
- However, the formal specification for patient
data, given below, requires further refinement in
order for patient data to be sufficiently
structured for software manipulation and
interpretation of values. - interface Patient_Data
- attribute string name
- attribute string type
- attribute sequence ltstringgt possible_values
- attribute string temporal_constraint
- attribute sequence ltSupplemental_Materialgt
didactics
24GLIF step types
- Conditional steps direct flow to one of two other
guideline steps, depending on the truth value of
a conditional. - Branch steps direct flow to one or more of a
number of guideline steps, according to a
non-boolean selection method. Branches are
"traversed" either in parallel (simultaneously)
or one at a time. - Synchronization steps are used in conjunction
with branch steps to synchronize flow of control
through multiple, parallel paths.
25Language 4 PROforma
26PROForma
Task
Decision
Action
Enquiry (query)
Plan (sequencing)
27Systems
- System Project
- Proforma PROMPT
- HELP HELP
- MLMs ??
- Protégé 2000 Protégé, Intermed, EON
- GAUDI Prestige
- ALGO
- OncoDoc Paris
- GEODE CM GEODE CM
28GEODE-CM
A system that combines guidelines with structured
data entry and data retrieval from
databases. Passive system - suggests decisions to
be made etc. Gives a clinical summary of the
information that is known about the
patient Actions - diagnostic tests to be done on
the patient transitions clinical management
states to which the patient may go next. Criteria
for moving states. Didactics - supplemental
information and notes.
29EON
Pari