RAPID PROTOTYPING MODEL

Information

  • Patent Application
  • 20210174273
  • Publication Number
    20210174273
  • Date Filed
    November 19, 2020
    5 years ago
  • Date Published
    June 10, 2021
    4 years ago
Abstract
Rapid prototyping of a process in a business domain, such as a healthcare domain or the United States healthcare domain, is disclosed. A computer is programmed to perform discrete event simulation (DES) of a scenario in the business domain. The DES is defined by a plurality of resources having resource attributes, a plurality of events having event attributes, and a plurality of entities having entity attributes. The computer is programmed to implement a DES simulator configured to run the scenario including performing time steps per resource in which the entities experience events.
Description
BACKGROUND

The following relates to the discrete event simulator arts, healthcare policy development arts, healthcare cost management arts, and related arts.


BRIEF SUMMARY

In one illustrative embodiment, a rapid prototyping system is disclosed for prototyping a process in a business domain. The rapid prototyping model comprises a computer programmed to perform discrete event simulation (DES) of a scenario in the business domain, the DES being defined by a plurality of resources having resource attributes, a plurality of events having event attributes, and a plurality of entities having entity attributes, the computer programmed to implement a DES simulator configured to run the scenario including performing time steps per resource in which the entities experience events. In some embodiments, the DES simulator is implemented in AnyLogic or Python. The computer may be further programmed to generate a synthetic population of entities upon which the DES simulator runs the scenario, and may be further programmed to generate outcomes for the scenario based on the running of the scenario, which may for example be presented on a display (e.g., an LCD display, plasma display, OLED display, or so forth). The outcomes for the scenario may include aggregated outcomes for the population, and/or disaggregated outcomes for defined segments of the population. The computer in some embodiments is programmed to run a baseline scenario that does not include a proposed innovation to the business domain, and an innovation scenario that includes the proposed innovation to the business domain, and the generated outcomes then include at least one comparison of the outcomes for the innovation scenario versus the outcomes for the baseline scenario. The computer may be further programmed to perform uncertainty analysis on the generated outcomes for the scenario, such as a scenario-based uncertainty analysis in which predefined scenarios are run by the DES simulator to test limits of the innovation, or a Monte Carlo-based uncertainty analysis in which scenarios generated by Monte Carlo sampling are run by the DES simulator to generate distributions of the outcomes. In some illustrative embodiments, the business domain is a healthcare domain, or more specifically the United States healthcare domain.


In another illustrative embodiment, a rapid prototyping method is disclosed for prototyping a process in a business domain. The rapid prototyping method comprises: using a computer, running a discrete event simulation (DES) of a scenario in the business domain, the DES being defined by a plurality of resources having resource attributes, a plurality of events having event attributes, and a plurality of entities having entity attributes, the running of the DES of the scenario including performing time steps per resource in which the entities experience events; and generating outcomes for the scenario based on the DES of the scenario. In some embodiments, the DES is implemented in AnyLogic or Python. In some embodiments, the method further includes, using the computer, generating a synthetic population of entities upon which the computer runs the DES of the scenario. In some embodiments, the computer is programmed to run DES of (i) a baseline scenario that does not include a proposed innovation to the business domain, and (ii) an innovation scenario that includes the proposed innovation to the business domain, and the generated outcomes include at least one comparison of the outcomes for the innovation scenario versus the outcomes for the baseline scenario. Some embodiments further include, using the computer, performing uncertainty analysis on the generated outcomes for the scenario, such as scenario-based uncertainty analysis in which the computer runs DES of predefined scenarios to test limits of the innovation or Monte Carlo-based uncertainty analysis in which the computer runs DES of scenarios generated by Monte Carlo sampling to generate distributions of the outcomes. In some illustrative embodiments, the business domain is a healthcare domain, or more specifically the United States healthcare domain.


In another illustrative embodiment, a non-transitory storage medium stores instructions readable and executable by a computer to perform a rapid prototyping method as set forth in the immediately preceding paragraph.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 presents an illustrative decision-making process, per Center for Medicare and Medicaid Innovation (CMMI) Payment and Service Delivery Innovations, from review of policies and procedures.



FIG. 2 diagrammatically shows a rapid prototyping system for prototyping a process in a business domain.



FIGS. 3A, 3B, and 3C present an example diagram showing elements of key simulator definitions and associated classes/attributes.





DETAILED DESCRIPTION

Rapid Prototyping Models disclosed herein comprise simulators (e.g. Python-based) of a healthcare policy system that models individuals moving through the healthcare system as a series of discrete events. Each event has a set of probabilistic outcomes and each simulated person has a set of attributes modifying that probability distribution. For economically driven decisions, the decision-making agent utilizes a net present value approach for their expected costs and benefits to make a cost-benefit analysis within a given budget constraint. As healthcare services are utilized, they are recorded using actual Centers for Medicare & Medicaid Services (CMS) claim codes (or other claim codes, e.g. insurance payer claim codes, which may be specific to a particular insurer, or so forth) and other data is recorded in high fidelity to allow detailed drill-down into the cause and effect behavior within the system. This allows for analysis of policy changes (specified as a scenario) while incorporating realistic outcome likelihoods with the potential for emergent behavior. All discrete event specifications are drawn from peer-reviewed literature, with limited exceptions that utilize transparent and clearly documented assumptions.


Healthcare policy changes, particularly in the arena of alternative payment models, are difficult to assess before pilot testing and current approaches depend heavily on highly biased expert judgement. CMS has spent billions of dollars designing, testing, and evaluating alternative payment models since 2012, but has shown a demonstrable effect (positive or negative) in a small set of their 70+ pilots, which take 3-5 years, expose patients, providers, and the government to risk, and cost a lot. The disclosed tool successfully replicated one of these studies and would allow for rapid testing of alternative designs to find the version most likely to succeed. This will also pay dividends during evaluation of models to help understand the internal workings of pilots when data is not available, and to drive new data collection during evaluations. By reducing the likelihood of testing an alternative payment model that is likely to fail, and improving the data collection during pilot implementation, this will reduce the failure rate, and increase the likelihood of identifying a positive or negative effect from the pilot.


The illustrative discrete event simulation disclosed herein is applied in the U.S. healthcare space, and Discrete Event Simulation with economic decision-making and healthcare service delivery is incorporated. Illustrative embodiments of the Discrete Event Simulation are focused on alternative payment and service delivery models.


In a workflow of operations where the simulation is started during the alternative payment model design process, the parameters of the proposed innovation are provided early to the development team and simulations on alternative designs start immediately. A combination of expert-provided scenarios and Monte Carlo simulations identify differences in proposed designs and the design reports are provided to the designers with recommendations about the relative likelihood of success for each design concept. During evaluation, as data from the real-world is provided, increasingly precise simulation runs will help to identify gaps in data collection and drive additional analysis into the real-world results, with a final product where the simulation has been calibrated to real-world implementation data.


Disclosed herein are embodiments of a Healthcare Technology Innovation Laboratory (HTIL) Rapid-Prototyping Model (RPM) for Payment and Service Delivery Models. Innovations in healthcare policy (e.g. payment and service delivery models) are currently pilot tested with small-scale comparative evaluations that are costly to implement, take several years to complete, expose participants to risk of harm, lack statistical power, and often result in inconclusive findings regarding the impact of the pilot. RPM will be a high-fidelity simulation capability that allows rapid prototyping of policy decisions for our clients before putting human subjects at risk. It will reduce cost by focusing on high value activities, and risk of failure for effectiveness studies by reducing uncertainty in the selection of innovations to pilot. The overall guiding approach is to build a simulation framework that is object-oriented, enabling analysts to add new, detailed models to test a variety of specific policy innovations in a short cycle to inform decisionmakers of the expected impacts of design decisions. The three main use cases are evaluation (i.e. evaluating the expected impact of an intervention to support decision-making about approving pilot testing), evaluation support (i.e. informing evaluation design by identifying where in the body of evidence there are the most significant gaps), and program integrity (i.e. using probabilistic information to identify situations where a performer is greatly exceeding expectations).


The RPM Framework is a design specification that enables integration and re-use of detailed event models and supporting infrastructure to model outcomes across a variety of policy domains, particularly payment and service delivery innovations. By re-using the generalizable elements of the framework, like iteration logic, synthetic populations, common healthcare events, and standards for interconnecting specific event models, the cost and time involved in the initial RPM Framework development can be leveraged for future problems. This will reduce the time from start to finish of simulating and analyzing the policy innovation. Documentation of the process will allow for full replications by teams outside of the analysis team and interoperability will be maximized by storing outputs in accessible, well-documented data storage formats.


The framework relies primarily on discrete event simulation, where a problem is abstracted as a process of events where a set of actors conditions the outcome of the event. An actor may be a patient, a doctor, or even an organization. Each “discrete event” comprises a series of options drawn from an independent probability distribution. Accordingly, at each event, an actor's features modify the probability distribution and a random draw is utilized to estimate their outcome. Actor features for individuals may include race/ethnicity, insurance status, gender, etc., while features for an organization might include region, volume of care, specific capabilities, etc. While each event is independent (making parameterization easier), the full path through an iteration of the model (some period) contains dependencies because different paths include and exclude encountering some sets of events for a given actor.


A synthetic population of actors (i.e. entities or objects) is estimated based on known characteristics (drawn from surveys, census, and other sources of data) and then each individual in the synthetic population works through the model in defined timesteps. Because the probability distribution of each function is conditional upon the actors' features, stratification is possible at the most micro-level of detail defined for an actor in the synthetic population. This population itself is generalizable a part of the framework and can be re-used with appropriate modifications (if there are case-specific risk factors to incorporate, for example).


As outlined in Table 1, three types of typical use cases are: Evaluation; Evaluation Preparation; and Program Integrity. In the Evaluation use case, the HTIL RPM is used to evaluate the expected impact of a given intervention. In the Evaluation Preparation use case, the HTIL RPM is used to design data collection strategies targeting the areas of greatest uncertainty or sensitivity to implementation for an intervention by assessing the evidence base quantitatively to support post-pilot evaluation of actual impact. In the Program Integrity use case, the HTIL RPM is used to assess the likelihood of achieving a given real-life scenario and then working back to re-construct the steps leading to that outcome to validate claims and other data.









TABLE 1







General use cases describing HTIL RPM expected utilization









ID
Name
Description





1
Evaluation
HTIL RPM is used to evaluate the expected impact of a




given intervention


2
Evaluation
HTIL RPM is used to design data collection strategies



Prep
targeting the areas of greatest uncertainty or sensitivity to




implementation for an intervention by assessing the




evidence base quantitatively to support post-pilot




evaluation of actual impact


3
Program
HTIL RPM is used to assess the likelihood of achieving a



Integrity
given real-life scenario and then working back to re-




construct the steps leading to that outcome to validate




claims and other data









The DES is performed, in some illustrative applications, in the context of a development process that (for example) follows the Agile Scrum methodology, where key user stories are defined as performance requirements and developers work in parallel to build components of the model during time-bound development sprints (typically two weeks). Each sprint focuses on producing a “minimally viable product” that represents a fully functional prototype. All code and relevant datasets will be maintained in a version-controlled repository. JIRA (a proprietary issue tracking product developed by Atlassian that allows bug tracking and agile project management) is suitably utilized for tracking user stories, tasks, and sprints. This is merely an illustrative implementation.


The purpose of sprints, following the development of initial infrastructure development, is to reduce forecasting uncertainty or increase performance. Forecasting uncertainty is the quantitative assessment of unknown information and impacts the precision of estimates (forecasting uncertainty is typically envisioned as confidence intervals). Each development sprint should add detail to existing “black boxes” where large assumptions are made and process steps are lumped together for simplicity. The improvement in forecasting uncertainty may apply to the aggregated outcomes (i.e. full population level) or the disaggregated outcomes (i.e. for specific stratified populations, i.e. defined segments of the population). Performance is defined as the amount of time required to prepare data inputs, run the simulator, and export the results.


The Modeling Domain is further described in the following, for a nonlimiting illustrative context of the U.S. healthcare system, in which reimbursement claims are described using Centers for Medicare & Medicaid Services (CMS) claim codes. More generally, the disclosed RPM can be employed in other healthcare contexts (e.g., outside the U.S.), and/or employing other types of claim codes and/or other healthcare reimbursement frameworks and/or descriptors. Even more generally, the disclosed DES simulators may find application in a wide range of other business domains, such as transportation policy development, transportation system cost management, educational policy development, educational system cost management, and so forth. The following is to be understood to be a nonlimiting illustrative example.


The core modeling domain for the RPM Framework is healthcare payment and service delivery model innovations, and, for this nonlimiting illustrative example, assumes a context of U.S. healthcare in which reimbursement employs CMS claim codes. A brief history is provided of Medicare and Medicaid reimbursement models and their connection to service delivery, and the new role the Center for Medicare and Medicaid Innovation (CMMI) plays in developing innovations to address shortcomings in this reimbursement system. Some of the general characteristics of the payment and service delivery model innovations that CMMI has put forward are also described. Decision-making criteria that CMMI faces to start implementation of a new pilot or to continue the pilot are also described.


Since Medicare and Medicaid were established in the 1960s, payment has relied on the concept of a Fee-For-Service payment model, where reimbursement is based on inputs to the process rather than the most appropriate care over an episode of illness or over the course of a year. Fee-for-service incentivizes providers to provide a large volume of services, even when better, lower-cost methods exist to treat a condition. In 1988 Medicare was authorized by Congress to test a new reimbursement model, the Coronary Artery Bypass Graft (CABG) bundled payment. Another model was tested in 2005 looking at Physician Group Practice payment models. Both reforms tied reimbursement to performance against quality measures. In the 2009 Affordable Care Act, Section 3021 created the Center for Medicare and Medicaid Innovation (CMMI) and gave it broad authorization to test new models that tie pay to performance against quality measures or implement changes to service delivery models. CMMI is authorized to test models brought forward by legislation (i.e. from legislators) or other sources based on the judgment of the Secretary of Health and Human Services (HHS).


Since the passage of the Affordable Care Act, CMMI has planned pilots for more than 70 new payment and service delivery models and completed 12 (as of February 2017, by our count of status=“No Longer Active” from the CMMI website, excluding 2 entries that are just summaries of categories of pilot groups). These model innovations target a variety of possible innovations that must meet certain conditions. At its core, a model innovation must either (1) reduce costs without affecting quality; (2) improve quality without affecting costs; or (3) improve quality and reduce costs. A variety of other decision criteria are utilized for prioritizing these model innovations, including the types of people served, the overall scale of the innovation's impact, and other factors outlined in CMMI's authorizing legislation.


The model innovations utilize interventions that fall broadly into the categories Evaluation; Evaluation Preparation; and Program Integrity, as previously described (note, this is drawn from a sample of completed models and models that have not yet been implemented accounting for 30 of the 70+ models), with slight variations. The definitions and categories were assigned by analysts based on text descriptions available from the pilot website or corresponding Fact Sheet to categorize similar interventions. These interventions are often combined to incentivize certain behaviors.


Interventions target a range of groups, typically Hospitals (10), Providers (6), Physicians (5), Accountable Care Organizations (4), and Beneficiaries (4). When an intervention targets a more specific group, it is coded accordingly (for example, a physician is also a provider, so if no more specific target information is provided, then that physician will be counted as a provider, not a physician). The groups that benefit directly from these interventions (other than financially) are primarily Medicare beneficiaries (only 5 address Medicaid or CHIPS) that range from broad populations to more discrete sub-groups. One of the decision factors affecting approval of a pilot is its impact disadvantaged groups. Some interventions specifically target only a subset of health conditions.


Outputs (see Table 2) are generated by an intervention and contribute to an outcome. Detailed outputs are not available from the described overview analysis of the payment and service delivery models and in many cases had to be inferred from general pilot descriptions. In this discussion, we focus on outputs specified by the summary descriptions. Outputs will be produced at a varying rate depending on the intervention and level of effort (i.e. how much a participating organization contributes). These outputs theoretically will drive changes for outcomes, defined in Tables 3 and 4.









TABLE 2







Innovation types, descriptions, and


frequency from sample of CMMI models










# of




Innovations


Innovation
(not mutually


Category
exclusive)
Notes












Advance
5
Interventions that provide advance


Payment

payment for a block of services (also




called capitation), or for investment in




infrastructure or for investment in




infrastructure to support quality




improvement activities


Bundled
6
Reimbursement is based on an


Payment

episode of care, typically involving an




initial admission and ending with




rehabilitation activities (e.g., knee




surgery)


Commu-
1
Interventions targeted broadly around


nication

communications


Data Sharing
5
Interventions that explicitly include data




sharing between parties that normally




would not share data. Often this is cost




and quality data.


Directed
1
Interventions that specifically re-direct


Payments

traditional fee-for-service payments to




different parties


Learning and
5
Interventions that include an aspect of


Diffusion

education through a centralized


Program

learning and diffusion program


Patient
3
Education targeting the patients as an


Education

intervention


Patient
1
Interventions that aim to engage


Engagement

patients in communication and shared




decision-making, as opposed to




education


Pay for
16
Pay is specifically tied to performance


Performance

against a set of quality indicators


Population-
3
Payment is based on a global budget


Based

for a population based on its risk


Payment

factors, a slight variation on Advance




Payment


Practice
7
Specific approaches to treatment are


Change

taught or incentivized directly to




change cost or quality factors


Regulatory
2
Revisions in regulation necessary to


Revision

allow or incentivize new behaviors




(typically called a waiver)


Shared Savings
8
Interventions that share cost savings




due to reimbursement savings between




CMS and another entity, typically a




doctor, hospital, or patient


Technical
3
Training is provided directly to


Assistance

participating organizations, staff, etc.
















TABLE 3







Outcome types, frequency, and definitions


for sampled CMMI models










#Outputs



Category
Mapped
Definition












Money
15
Financial changes


Education
13
Learning or educational opportunities such as




trainings


Commu-
8
Outreach, etc. that is not labeled as education


nication


Service
7
Changes in the types or numbers of medical




services provided


Collab-
5
Changes in collaborative activities between


oration

disparate groups


Data
5
Changes in data access or provision


Policy
5
Changes in policy such as new statements of




support for a given approach


Risk
4
Changes in risk burden (i.e., who takes on




the risk for poor performance)


Legal
4
Changes in legal obligations, such as




contracts


Measurement
4
Changes in measurement approaches


Resources
3
Changes in availability of resources,




including human capital


Planning
2
Changes in planning approach


??
2
Undefined


Organization
1
Changes in organizational structure
















TABLE 4







Outcomes types, frequencies, and definitions


from sampled CMMI models










# Outcomes



Category
Mapped
Definition












Quality
41
Outcomes related to care quality or




patient outcomes


Cost
20
Outcomes related to financial




outcomes


Care Coordination
14
Outcomes related to coordinating




care across different caregivers


Patient Knowledge
6
Outcomes related to informing




patients or otherwise educating them


Efficiency
6
Outcomes focused on reducing




redundancy or linking cost and




quality explicitly


Practice
5
Outcomes related to long-term




change in practice


Education
2
Outcomes related to education for




providers


Patient Outcome
2
Outcomes for patient specific




achievement (e.g., weight loss,




cardiac fitness)


Infrastructure
1
Outcomes for changes in




infrastructure


??
1
Undetermined how to categorize:




“Decreased incentive for




hospitalization”


Coverage
1
Outcomes related to changes in




coverage.









Outcomes are the terminal goals of a given intervention. The outcomes may be presented on a display (e.g., an LCD display, plasma display, OLED display, or so forth), printed by a printer or other marking engine, stored in a file, and/or otherwise utilized, They are the things that an intervention aims to change, but cannot do directly. They depend on the outputs and a variety of other factors such as implementation fidelity and other intervening variables. For this modeling domain, the primary outcomes of interest are quality and cost.


In addition to understanding the types of activities and outcomes at a general level, it is helpful to understand the decision-making environment that works to approve these pilots. The key questions CMMI tends to grapple with (again, in this specific example directed to DES simulation of CMS) in decision-making are outlined as follows. First order issues (i.e. must do at all) include reducing costs as defined in CN: USG, 2012, 42 U.S.C. 1315a Section 1115a, or increasing quality of care, or both. These issues can be evaluated, and fit into the listing of allowed model types from CN: USG, 2012, 42 U.S.C. 1315a Section 1115a. Second order issues (i.e. it should do as much of this as possible, in no particular order) include giving providers flexibility to exercise judgment, furthering the aims of health equity (i.e. increasing care to the disadvantaged and not excluding anyone new), utilizing health information technology (IT), contributing to integration and care coordination among teams, enhancing patient decision-making and agency, and communicating more effectively with patients. As the pilot is underway, a contractor is responsible for implementing the innovation and a separate, independent contractor is responsible for evaluating the pilot. These evaluations rely heavily on quality measures representing outcomes and treat the model innovation as a black box without detailed process modeling (for the most part). The results of the pilot evaluation inform the decision to shut down, expand, or continue in its current state a given pilot.


To constrain the possible set of issues that the HTIL RPM will address, we have identified a set of key questions that it will answer. In each case, the question is framed as “Given the set of assumptions and modeling constraints selected,”. The list of questions includes the following.


What was the change in specified quality measures for the pilot groups, compared to the baseline/comparison group (fee for service)? In addressing this question, the HTIL RPM should provide the ability to stratify down to core groups (race, SES, gender, Medicare, Medicaid, rural, urban, etc.) depending on the focus of the pilot.


What was the change in cost for the pilot groups, compared to the baseline/comparison group (fee for service)? In addressing this question, the HTIL RPM should provide the ability to stratify down to core groups (Medicare, Medicaid, provider, hospital, provider group, patient, community of patients).


What specific aspects of variation in implementation of the model (both planned and unplanned) affect outputs and outcomes and how? That is, if the model works, why does it work? For evaluation design purposes, reframe as “what are the areas of greatest uncertainty to target data collection for?” For program integrity purposes, reframe as “What is the likelihood of accomplishing a given level of improvement?”


Under what set of scenarios (or in a robust uncertainty analysis) do these results change and how can the design be optimized to maximize the values for each question?


How was patient agency and decision-making affected?


How was care coordination between specified groups affected?


These key questions will drive development of the RPM framework.


Next, the overall workflow for the RPM Framework is described, as well as its envisioned fit into the decision-making framework for CMS.


The current decision-making framework for CMS relies heavily on a stakeholder-driven process and public comment periods. FIG. 1 shows the general steps in the life-cycle of a model innovation pilot. A pilot is proposed 10 and it goes to one of two reviewing bodies 12, 14. One, PTAC (Physician-Focused Payment Model Technical Advisory Committee) 12 reviews only applications that are for Physician-Focused Payment Models. All other reviews work through another, less defined mechanism 14, typically including staff and/or contractors for CMMI. In each case, stakeholder input and public comment are key decision inputs for decision 1a 16 of the PTAC review 12 and decision 1b 18 of the CMMI review. The PTAC review 12 also relies on a governing board review with a public meeting component where they review data submitted with a given proposal. A high-level overview of the types of questions considered during an application from CMMI suggests a similar process might be suitable.


Two different gate reviewing bodies 20, 22 filter opportunities to prepare for review 20 by the Secretary of HHS. This would support Use Case 1, Evaluation 24. At this point, it is not clear if there is a defined process that involves contracting analysis out, but we assume that the opportunity exists. As a contributor to the evidence-base of a proposed idea, the RPM Framework could be leveraged as evidence by either a proposer or the review panel. Hence, HTIL RPM can be used for Use Case 2—Evaluation Preparation. Finally, as it applies to pilots 26, Use Case 3—Program Integrity would likely apply to fully implemented (i.e. “expand”) innovations 28.


The disclosed process for employing the RPM Framework involves a series of steps to parameterize existing, reusable model components and build new model components. This concept of operations is written with terminology consistent with Use Case 1, but generally applies across all three use cases. Points of departure are explicitly noted. The general proposed process is as follows.


First, background research is performed. This entails working with proposer documentation to develop a logic model describing the intervention, its expected outputs, and the expected outcomes. Key aspects of the logic model will include linkages showing how resources are converted at the intervention into outputs and how those outputs convert into outcomes. An evidence basis for these causal linkages will support the parameterization of model components.


Next, parameterization of the baseline model is performed. The baseline model represents the expected outcomes under current standards (e.g. Fee-for-service) and provides a comparison baseline. The payment and service delivery models for the baseline model are all generalizable for future model runs, but may require expansion to meet the specific needs of a given model innovation. For example, if the model has only been run against a generic set of cardiac conditions, and a comparison against the Coronary Artery Bypass Graft (CABG) intervention is proposed, the black-box elements of the baseline models for cardiac conditions may require additional detail.


Next, parameterization of the innovation model is performed. This entails, using the logic model and evidence basis, determining the core generalized components of the RPM Framework to re-use, and any previously utilized sub-models that can be re-purposed. Relevant parameters and conditions are identified for those models and sub-models to tailor to this specific policy innovation. Utilizing the evidence basis and logic model, any new sub-models are identified and developed needed.


The uncertainty analysis approach is next determined. An uncertainty analysis facilitates understanding the potential impacts of changes in parameterization of the model. Two approaches are suitably considered. In a scenario-based analysis approach, the analyst defines a-priori cases to test the limits of the model based on their understanding of model function, the logic model, and data constraints. Each of these cases (or scenarios) will be run and compared against the primary performance case. This is true of both the Baseline Model and the Innovation Model case. Alternatively, in a Monto-Carlo-based analysis approach, the range of potential uncertainties in the model are identified and Monte-Carlo methods are used to simulate them at random to estimate the distribution of expectations. This approach is most desirable as it depends less on analyst judgment.


Model runs are next performed. Based on the uncertainty analysis approach, the model is run as needed and model outputs are generated for analysis.


The results are then analyzed. Results are suitably compared between the Baseline Model and the Innovation Model, and results from the uncertainty characterization are preferably considered to make robust analysis. If needed, new uncertainty scenarios may be developed to address any difficult to explain variation.


Finally, the results are presented. In one suitable approach, a briefing document summarizing the method, the scenarios, and the model results is prepared at a level sufficient for peer-reviewed publication. Additionally or alternatively, a policy-level briefing may be prepared to communicate the results to decisionmakers in a short format appropriate for the venue and submit.


Some further illustrative examples of the HTIL RPM are next described.


With reference to FIG. 2, the HTIL RPM utilizes Discrete Event Simulation (DES) as a primary modeling framework. The rapid prototyping system for prototyping a process in a business domain comprises a computer 40 programmed to perform discrete event simulation (DES) of a scenario 42 in the business domain. The DES is defined by a plurality of resources 44 having resource attributes, a plurality of events 46 having event attributes, and a plurality of entities 48 having entity attributes. The computer 40 is programmed to implement a DES simulator 50 configured to run the scenario 42 including performing time steps per resource 44 in which the entities 48 experience events. The computer 40 is preferably further programmed to generate a synthetic population 52 of the entities upon which the DES simulator 50 runs the scenario 42, and to generate outcomes 54 for the scenario 42 based on the running of the scenario 42. The outcomes 54 may be presented on a display 56 (e.g., an LCD display, plasma display, OLED display, or so forth), and/or printed by a printer or other marking engine, stored in a file, and/or otherwise utilized.


In some embodiments, the computer 40 is programmed to run a baseline scenario 62 that does not include a proposed innovation to the business domain, and an innovation scenario 64 that includes the proposed innovation to the business domain. The generated outcomes 54 then include at least one comparison of the outcomes for the innovation scenario 64 versus the outcomes for the baseline scenario 62. The computer 40 may then be further programmed to perform uncertainty analysis 66 on the generated outcomes for the scenario. For example, the uncertainty analysis 66 may comprise a scenario-based uncertainty analysis in which predefined scenarios are run by the DES simulator 50 to test limits of the innovation. In another approach, uncertainty analysis 66 may comprise a Monte Carlo-based uncertainty analysis in which scenarios generated by Monte Carlo sampling are run by the DES simulator 50 to generate distributions of the outcomes 54.


DES is best used when the focus of a problem is modeling a system in detail and attaining results at a micro-level (e.g. individuals with specific features/characteristics). Dynamics in DES are driven by discrete event occurrence. “Event occurrence” is defined by a specified probability distribution conditioned on the features of a given “person” in the synthetic population. Experiments are conducted by modifying process structure such as the pathways between events or the probabilities associated with a specific event outcome.


Factors driving this decision include the types of questions specified in Core Assumptions>Key Questions, the desired level of detail (microlevel), and development approach (iterative, focused on decreasing uncertainty from the top-down). Alternative modeling approaches that might be employed include Systems Dynamics (SD) models (but these do not allow for micro-level analysis) and Agent-Based Models (ABM) (but these are inherently more complex, because of the large number of variables within an agent model). Although ABM is more granular than DES and SD, it requires a detailed understanding of the model component characteristics and interactions and demands far more development and testing effort which is not feasible within the current constrains of this task. The level of abstraction using DES is optimal in that it will allow for development and analysis of a reasonably granular model within the task constraints.


Some key definitions of the DES simulator are presented as follows. Table 5 presents some vocabulary used in describing the DES simulator. FIGS. 3A, 3B, and 3C present an example diagram showing elements of key simulator definitions and associated classes/attributes. FIG. 3A depicts a timestep of the simulation, including a timestep path running from “Start” to “Event 1” to “Outcome 2” to “Event 3” to “Outcome 3” to “End”. An alternative timestep path would run from “Start” to “Event 1” to “Outcome 1” to “Event 2” to “Outcome 3” to “End”. FIG. 3B diagrammatically shows illustrative resources having resource attributes and illustrative events having event attributes. FIG. 3C shows a legend of symbols used in the diagrams of FIGS. 3A and 3B.









TABLE 5







key vocabulary










Name
Definition
Comments
Examples





Entities
Objects that have attributes,
Python Class
Patients, Doctors


(processes)
experience events, consume



resources, and enter queues



over time


Attributes
Features specific to an entity
Class attributes
Age, sex, race,



that allow it to carry

health status,



information.

past event


Events
Things that can happen to an
Initiated or
Clinical condition,



entity or an environment. A
captured by class
adverse drug



discrete element of the model
attributes, and
reaction, clinical



with at least one outcome
methods,
decision,



conditioned on a set of inputs.
simulation
treatment




Environment




(SimPy Yield




utilities)


Resource
An object that provides a
Python Class
Building,



service to an entity (may

Organizations,



require time). Attributes of

etc.



resource affect the probability



distribution of an event


Queue
If a resource is occupied when
SimPy



entity needs it, then that entity



must wait, forming a queue.



Queues can have a maximum



and alternative approaches to



calling entities from queues,



can be defined.


Time
An explicit simulation clock
SimPy
Hard to think of



keeps track of time.

examples, pretty



Referencing this clock makes

fundamental to



it possible to track interim

the universe.



periods. (Discrete handling of



time means that the model



can efficiently advance to the



next event time.)


Interaction
Entities competing over a
Specified with the
Patients waiting



resource.
class attributes,
for a service




and methods, and




simulation




Environment




(SimPy)


Outcome
The result of an event, may be

Patients



qualitative (i.e., a yes/no

diagnosed with



decision) or quantitative (i.e.,

flu, Time waiting



modeling the time to recovery

for doctor



for an illness once all care



decisions are completed.)


Path
The connection between two



events. Nothing happens on a



path, but it serves to connect



events.


Timestep
A period of time over which a

Episode of care



set of events are expected to



occur in a defined order.



Incorporates elements of time,



events, and paths.


Timestep
All of the events experienced

During my


Path
by a given entity in a timestep.

episode of care . . .


Synthetic
An estimated population

Population of


Population
constructed from known

FQHC patients,



features of a real population

based on



for the purposes of modeling

empirical



population dynamics.

distributions


Scenario
A specific set of starting

Assuming that x



conditions and assumptions

is set to 10 and y



reflecting the state of the

is set to 5 . . .



simulator parameterization.









There are two different approaches to developing the DES simulator. The first approach is to use off-the-shelf DES simulation software, and the alternative is to develop the simulation software using an open source software platform such as Python. The first option allows for developing a prototype model very quickly, with minimal software development work required, allowing more time for testing and model refinement. The latter approach allows for developing a more flexible and configurable simulation tool that can be modified more readily to solve problems that are too unique or specialized to be modeled using an off-the-shelf software tool easily. The approach employed in the illustrative embodiments is to build the tool in Python, after performing a short performance test and deciding that flexibility of data inputs and outputs in Python. In both cases, it is possible to specify a set of features desired in a simulation tool. The overall goal is to support rapid prototyping (i.e. limited compile times, simple interface, integrated documentation, etc.), research reproducibility (plain text, version controlled inputs, outputs, and code), and speed. The simulator is responsible for simulation runs (not data preparation or data analysis) and exporting data into a format suitable for archiving and entering into version control to support reproducibility. Accordingly, the simulator preferably utilizes software that: is object-oriented; modular, allowing for objects to be added and used selectively depending on modeling scenario; extensible, allowing new functionality to be added as needed; has utilities for unit testing, including a coverage checker (to assess the proportion of code that has associated tests); has utilities for system testing, allowing for discrete test cases demonstrating end-to-end functionality of the simulator; is platform independent (i.e. compiles and runs on any environment), or can be made platform independent (i.e. can be compiled, then deployed to run), specifically between a Linux and Windows environment; can run in parallel, allowing multiple scenario runs in parallel (for uncertainty testing); has utilities for data visualization; is suitable for quick prototyping; is free or open source; has developer tools designed to ease development, build dashboards, and perform other maintenance tasks; has an existing, broad library of open source libraries to ease development; and provides exception handling and a simple logging infrastructure.


One existing software tool is called AnyLogic which is a multimethod simulation tool supporting DES, ABM and SD simulation approaches. This software comes with a graphical user interface (GUI) modeling language and is extensible using Java code. The code software contains built in libraries, including the Process Modeling Library, the Pedestrian Library, the Rail Library, and the Fluid Library. It also supports 2D and 3D animation. The model can be exported as a Java application that be run separately or integrated with other software. Battelle currently has an active single license on a common computer (e.g. PC) accessible by team members for this project. The primary requirements to use this tool to develop a simulation tool is run it on a single common PC, which a Windows system.


In the following, some quality and cost/benefit considerations are discussed, as regards certain practical considerations in selecting a platform for implementing the DES. A suitable open-source toolset for this task is Python which can run on one or more computers having a Windows, Linux, and/or MacOS operating system. By way of illustration the Linux platform is assumed, e.g. with style checking by Pylint configured to match a chosen Style Guide defined in Python Style Guides and Best Practices. The unit testing and code coverage checking will be an integral part of the development phase using Python's unittest testing framework. By way of nonlimiting illustrative example, the Anaconda python distribution is suitable, with Python version 3.6. The choice of integrated development environment (IDE) suitably depends on personal preferences if the other requirements are met. Some options are PyCharm, and PyDev. Version control will be handled with Git. A ‘semi-agile’ development method for task management as defined in the Assumptions: Development Approach. Table 6 provides a comparison of AnyLogic and Python software based on specified characteristics.









TABLE 6







Comparison of AnyLogic and Python software









Requirement
AnyLogic
Python





Object-oriented
Yes, with pre-specified
Yes, no pre-specified



object types and ability
object types



to build new ones; Java


Modular
Yes
Yes


Extensible
Yes (using Java
Yes



integration)


Unit testing
Unknown
Yes, unit-testing library.




Coverage checks with




“Coverage” app


System testing
Unknown
Yes, same as unit testing


Platform
Yes, using native Java
Yes; Cannot be compiled


independence
implementation; Can
and run as standalone



compile models and
application



run as a standalone



application; As



currently deployed,



only on Windows


Can run in
Yes; As currently
Yes, with limitations


parallel
deployed, no
imposed by Global




interpreter Lock, other




C-implementation




libraries or a specific




job-dispatcher


Utilities
Yes, fully integrated
Libraries to support


for data

building data


visualization


Suitability
Yes, intuitive user
Yes, simple integrated


for quick
interface, intended for
documentation, no


prototyping
rapid prototyping
graphical user interface


Free or
No. Quite expensive with
Yes


open-source
restrictive licensing rules


Developer
Intuitive GUI for model
Great tools, no GUI


Tools
development and to



support analysis


Existing, broad
Yes, but undetermined
Yes, but mostly at a


library of open
appropriateness
basic level requiring


source libraries

development


Provides exception
Unknown
Yes, a key design


handling and

component of Python


simple logging









The primary trade-off between AnyLogic and Python relates to the availability of the Graphical User Interface (GUI) vs. an open-source approach. One comes with a real cost in terms of purchase price and limitations of portability (AnyLogic), and the other comes with cost related to staff development time. Over a long period, the in-house Python solution is likely to result in a new, innovative approach with great flexibility (while incurring maintenance and new development costs), while AnyLogic is likely to incur lower costs in terms of maintenance and new development, but higher actual costs for ownership. In the short term, the Python solution will be costlier to develop new models, but will gain economies of scale and a unique capability. In the short term, AnyLogic imposes constraints (although limited) on model design, but gains in economy of scale will be smaller (because many of those improvements to the libraries have already been made).


Another task in the development process is to cross check and test the simulation results with the ‘truth’ values. To that end, a set of specific use cases are suitably developed, some of which address edge cases and specific scenarios that can be used to check the veracity of the simulation results. The ‘truth’ values for the use cases may be developed using R or excel spread sheets.


Data requirements are next described. The illustrative modeling domain is primarily claims data, as it is commonly used for reporting pilot effectiveness and will map well to reports of impact from pilot evaluations (for reproducibility), the information processing needs of our potential clients, and available empirical data. Additionally, survey data may be utilized when necessary (if no claims-based outcome measures are available) and population-level data as needed (e.g. census, population risk factors, etc.).


The data needed to parameterize the models differs from the data needed to replicate real-world evaluation findings. In each case, it is not necessary to have raw data containing identifiable information. Instead, synthetic datasets drawn from the real-world probability distributions (but simulated) or information about the distribution of a given dataset or set of outcomes can be utilized.


Data for parameterization is suitably defined at the event level. For each event, there are several risk factors and a pre-defined probability distribution. If we treat each event initially as having a uniform probability across outcomes, that maximizes uncertainty. Any data analysis that can affect the assumption of uniform probability should serve to reduce uncertainty. Because each event is considered independent, it falls to the model developer to select the most appropriate dataset to build the probability distribution. Where data is not available, and information exists to improve upon the uniform probability distribution, then that information will be utilized. Potential sources of information include (in prioritized order): (1) Peer-reviewed summary data or coefficients with estimates of uncertainty (e.g. standard errors); (2) internal analysis of datasets (possibly replicating findings from sources that are not peer-reviewed); (3) Estimates of probability from a large, independent crowd of experts (using well-established estimation methods, such as Delphi, and maintaining extensive documentation); and (4) Estimates from a small group, or an individual expert (using well-established estimation methods, such as Delphi, and maintaining extensive documentation). The process for incorporating data for parameterization may suitably include at least one within-team peer review to validate assumptions, quality, and level of documentation.


Data for replication may be based on the specific outcomes identified in evaluation reports from pilot evaluators. These outcomes are preferably reported quantitatively, and allow for direct comparison with the outcomes modeled by the HTIL RPM. Outcomes that are qualitative may still be desirable if they are the only tool available.


Supporting infrastructure in the case of AnyLogic includes Common PC access and a software license. Supporting infrastructure in the case of python includes: Version Control (e.g. Git server); Machines for model runs; and Machine for cross checking and development work, in addition to HPC, include Oracle VM Virtual Box and Linux Virtual Machines and personal computers (used for R). Both Python and R are open source packages and are readily available for downloading. Furthermore, the rapid prototyping system software and associated parameters and other DES data are suitably stored on a non-transitory storage medium that is readable and executable by the computer to implement the DES simulator and associated outcomes analysis (e.g. aggregating outcomes for the population or generating disaggregated outcomes for defined segments of the population, performing uncertainty analysis, and so forth). The non-transitory storage medium may, for example, comprise a hard disk or other magnetic storage medium, a solid state drive (SSD) or other electronic storage medium, an optical disk or other optical storage medium, various combinations thereof, or so forth.


Table 7 presents some illustrative user stories for development, descriptions, priority and status.









TABLE 7







User Stories








Key
Summary





HTIL-597
change numberOfAnnualTrainings from constant to uniform



draw and include it in the json output file.


HTIL-595
updateRunTimeParameters.csv in rpm-scenarios repo


HTIL-593
Modify the implementation of the doctor capability multiplier


HTIL-585
As a user. I can “delete” my own scenarios or experiments,



but they are only hidden from view


HTIL-576
As a user. I can click on a parameter in the scenario builder



and see the distribution and


HTIL-575
As a user, I can download an HPC batch file for an



experiment


HTIL-574
As a user, I can download a zipped file of the experiment



design


HTIL-573
As a user, I can launch an experiment from the experiments



view page


HTIL-572
As a user, I can browse public and my private experiments



in a table view (experiments view)


HTIL-571
As a user, I can create an “experiment” from a set of



population and runtime scenarios


HTIL-570
As a user, I can create runtime scenario based on the current



version of RPM


HTIL-569
As a user, I can create a population scenario based on the



current version of RPM


HTIL-567
As a user, I can login to a web interface


HTIL-447
Parameterize Wellness Check Initial Conditions


HTIL-314
Plot of no show, go to ED, stay home vs. day


HTIL-313
Scatter plot of appointment time per day


HTIL-312
Plot number of appointments per day


HTIL-149
As a user, I should be able to specify a set of scenarios to



run a qualitative uncertainty characterization


HTIL-148
As a user, I should be able to specify and run uncertainty



characterization using a monte-carlo approach


HTIL-147
As a developer, I should be able to iterate though a series



of events, defined as a single Timestep path where state



information is passed through synthetic


HTIL-146
As a developer, I need a structured way of generation event



modules


HTIL-145
As a user, I should be able to get data out of the simulation



in a structured, ready to analyze format


HTIL-144
As a developer, I can specify ranges with specific likelihoods



for all inputs and outputs on events


HTIL-143
As a developer, I can specify an arbitrary number of events,



with linkages to other paths for a simulation model run


HTIL-142
As a user, I can pass a synthetic population to the simulator



and have a graceful failure


HTIL-141
As a developer, I can build a synthetic population from a set



of known distributions


HTIL-140
As a user, I should be able to input starting data from a



pre-computed scenario









For the purposes of replication, HTIL RPM may be judged against the reported metrics from the relevant pilot evaluation report. A scoring matrix consisting of a 0-1 score for each dimension may be utilized. The accuracy measure will be calculated by dividing the total score from the scoring matrix, by its maximum score. Over time, the objective of the modeling approach will be to improve this score. For the purposes of replication analysis, we are interested in how the scores were generated and better understanding differences. The following heuristics will be used for scoring: Qualitative outcomes (i.e. binary) will be scored using log loss, e.g. normalized onto a 0-1 scale, where 1 is better; and Quantitative results (i.e. continuous or count). The quantitative results may be compared qualitatively by assessing whether the simulated results and the actual results from the pilot evaluation overlaps using 95% confidence intervals.


While described with respect to the U.S. healthcare policy development and healthcare cost management domains, it will be appreciated that the disclosed DES simulators may find application in a wide range of other business domains, such as transportation policy development, transportation system cost management, educational policy development, educational system cost management, and so forth.


The preferred embodiments have been illustrated and described. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims
  • 1. A rapid prototyping system for prototyping a process in a business domain, the rapid prototyping model comprising: a computer programmed to perform discrete event simulation (DES) of a scenario in the business domain, the DES being defined by a plurality of resources having resource attributes, a plurality of events having event attributes, and a plurality of entities having entity attributes, the computer programmed to implement a DES simulator configured to run the scenario including performing time steps per resource in which the entities experience events.
  • 2. The rapid prototyping system of claim 1 wherein the computer is further programmed to generate a synthetic population of entities upon which the DES simulator runs the scenario.
  • 3. The rapid prototyping system of claim 2 wherein the computer is further programmed to generate outcomes for the scenario based on the running of the scenario.
  • 4. The rapid prototyping system of claim 3 wherein the computer is programmed to run: a baseline scenario that does not include a proposed innovation to the business domain, andan innovation scenario that includes the proposed innovation to the business domain;wherein the generated outcomes include at least one comparison of the outcomes for the innovation scenario versus the outcomes for the baseline scenario.
  • 5. The rapid prototyping system of claim 4 wherein the computer is further programmed to perform uncertainty analysis on the generated outcomes for the scenario.
  • 6. The rapid prototyping system of claim 5 wherein the uncertainty analysis comprises a scenario-based uncertainty analysis in which predefined scenarios are run by the DES simulator to test limits of the innovation.
  • 7. The rapid prototyping system of claim 5 wherein the uncertainty analysis comprises a Monte Carlo-based uncertainty analysis in which scenarios generated by Monte Carlo sampling are run by the DES simulator to generate distributions of the outcomes.
  • 8. The rapid prototyping system of claim 3 wherein the outcomes for the scenario include aggregated outcomes for the population and disaggregated outcomes for defined segments of the population.
  • 9. The rapid prototyping system of claim 3 wherein the computer includes a display on which the generated outcomes are presented.
  • 10. The rapid prototyping system of claim 1 wherein the DES simulator is implemented in Python.
  • 11. The rapid prototyping system of claim 1 wherein the business domain is a healthcare domain.
  • 12. The rapid prototyping system of claim 1 wherein the business domain is the United States healthcare domain.
  • 13. A rapid prototyping method for prototyping a process in a business domain, the rapid prototyping method comprising: using a computer, running a discrete event simulation (DES) of a scenario in the business domain, the DES being defined by a plurality of resources having resource attributes, a plurality of events having event attributes, and a plurality of entities having entity attributes, the running of the DES of the scenario including performing time steps per resource in which the entities experience events; andgenerating outcomes for the scenario based on the DES of the scenario.
  • 14. The rapid prototyping method of claim 13 further including: using the computer, generating a synthetic population of entities upon which the computer runs the DES of the scenario.
  • 15. The rapid prototyping method of claim 13 wherein the computer is programmed to run DES of: a baseline scenario that does not include a proposed innovation to the business domain, andan innovation scenario that includes the proposed innovation to the business domain;wherein the generated outcomes include at least one comparison of the outcomes for the innovation scenario versus the outcomes for the baseline scenario.
  • 16. The rapid prototyping method of claim 13 further comprising: using the computer, performing uncertainty analysis on the generated outcomes for the scenario.
  • 17. The rapid prototyping method of claim 16 wherein the uncertainty analysis comprises a scenario-based uncertainty analysis in which the computer runs DES of predefined scenarios to test limits of the innovation.
  • 18. The rapid prototyping method of claim 16 wherein the uncertainty analysis comprises a Monte Carlo-based uncertainty analysis in which the computer runs DES of scenarios generated by Monte Carlo sampling to generate distributions of the outcomes.
  • 19. The rapid prototyping method of claim 13 wherein the business domain is a healthcare domain.
  • 20. A non-transitory storage medium storing instructions readable and executable by a computer to perform a rapid prototyping method comprising: using a computer, running a discrete event simulation (DES) of a scenario in the business domain, the DES being defined by a plurality of resources having resource attributes, a plurality of events having event attributes, and a plurality of entities having entity attributes, the running of the DES of the scenario including performing time steps per resource in which the entities experience events; andgenerating outcomes for the scenario based on the DES of the scenario.
Parent Case Info

This application claims the benefit of U.S. Provisional Application No. 62/945,633 filed Dec. 9, 2019 and titled “RAPID PROTOTYPING MODEL”. U.S. Provisional Application No. 62/945,633 filed Dec. 9, 2019 and titled “RAPID PROTOTYPING MODEL” is incorporated herein by reference in its entirety.

Provisional Applications (1)
Number Date Country
62945633 Dec 2019 US