Knowledge Acquisition for Clinical-Trial Selection Savvas Nikiforou Eugene Fink Lawrence O. Hall Dmitry B. Goldgof Jeffrey P. Krischer

Expert System The system analyzes a patient’s data and determines whether the patient is eligible for clinical trials at the H. Lee Moffitt Cancer Center.

Expert System Guides a clinician through related questions Identifies appropriate medical tests Selects matching clinical trials Minimizes pain and cost of selection process

Outline Eligibility decisions Knowledge base Knowledge entry Experiments

Example: Eligibility Criteria Female, older than 30 No prior surgery Breast cancer, stage II or III

Example: Questions Sex: Age: Female Male 25

Example: Conclusion Patient is not eligible

Example: Questions Sex: Age: 35 Female Male

Example: Questions Cancer stage: Prior surgery? Yes No I II III IV

Example: Conclusion Patient is eligible

Full Functionality Orders and groups the questions Considers multiple clinical trials

Outline Eligibility decisions Knowledge base Knowledge entry Experiments

Main Objects Questions Medical tests Eligibility criteria

Types of Questions Yes / No Multiple choice Numeric

Tests A medical test answers several questions. It involves certain pain and cost.

Eligibility Criteria A logical expression that determines eligibility for a specific clinical trial

Example: Criteria AND Age > 30 Prior-surgery = NO OR Cancer-stage = II Cancer-stage = III

Outline Eligibility decisions Knowledge base Knowledge entry Experiments

Tests and Questions Adding tests Modifying a test Adding yes/no questions Adding multiple choice questions Adding numeric questions Deleting questions

Adding Tests Test name: Cost: Pain: Yes/NoM-ChoiceNumericDeleting Adding Modifying Mammogram

Adding Yes/No Questions Breast cancer? Text Yes/NoM-ChoiceNumeric Adding Modifying Deleting

Adding Multiple Choice Questions TextOptions Yes/NoM-ChoiceNumeric Adding Modifying Cancer stage I II III IV Deleting

Adding Numeric Questions TextMinMax Tumor size 250 Yes/NoM-ChoiceNumeric Adding Modifying Deleting

Eligibility Criteria Adding eligibility criteria Selecting tests Deleting expressions Editing questions Defining an expression Selecting questions

Example: Eligibility Criteria Female, older than 30 Breast cancer, stage II Post-menopausal or surgically sterilized

Adding Eligibility Criteria Adding criteria Selecting tests 001Clinical trial A Trial numberTrial name Deleting expressions Editing questions Defining an expression Selecting questions

Selecting Tests General questions Blood test Mammogram Biopsy Urine test Adding criteria Selecting tests Deleting expressions Editing questions Defining an expression Selecting questions

Selecting Questions I II III IV Cancer stage: Age:From:To: Post-menopausal? Yes Surgically sterilized? Yes Adding criteria Selecting tests Deleting expressions Editing questions Defining an expression Selecting questions Prior surgery? No Yes

Defining an Expression Cancer-stage = II Surgically-sterilized = YES Post-menopausal = YES Age > 30 Adding criteria Selecting tests Deleting expressions Editing questions Defining an expression Selecting questions

Defining an Expression AND Adding criteria Selecting tests Deleting expressions Editing questions Defining an expression Selecting questions Cancer-stage = II Surgically-sterilized = YES Post-menopausal = YES Age > 30

Defining an Expression Adding criteria Selecting tests Deleting expressions Editing questions Defining an expression Selecting questions Surgically-sterilized = YES Post-menopausal = YES AND Age > 30 Cancer-stage = II

Defining an Expression Adding criteria Selecting tests Deleting expressions Editing questions Defining an expression Selecting questions Surgically-sterilized = YES AND Age > 30 OR Post-menopausal = YES Cancer-stage = II

Defining an Expression Adding criteria Selecting tests Deleting expressions Editing questions Defining an expression Selecting questions AND Age > 30 OR Post-menopausal = YES Cancer-stage = II Surgically-sterilized = YES

Outline Eligibility decisions Knowledge base Knowledge entry Experiments

Performance of sixteen novice users Entering tests and questions Entering eligibility criteria

Entering Tests and Questions Learning curve

Entering Eligibility Criteria Learning curve

Summary Learning time: 1 hour Adding a test: 2 to 10 minutes Building a knowledge base for Moffitt breast-cancer trials: 8 to 10 hours Adding eligibility criteria: 30 to 60 minutes

Main Results Formal model of selection criteria Representation of related knowledge Friendly interface for knowledge entry