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Five checks on what a fitted model releases, each with its pass criterion. The first three ask whether the fingerprint holds anything about one patient that it should not: a per-patient table, an identifier, or a single patient's value. The fourth recounts the smallest group of patients behind each kind of released frequency – arm sizes, attendance, dose-change rates, categorical levels, carried values, and the levels the schema keeps for factor columns and binary or ordinal endpoints – on both sides of it, since "one patient missed this visit" discloses as much as "one patient came". The fifth asks how far any one patient moves a released estimate, from the individual random effects for the population model, from each subject's baseline for the PD shapes, and by leaving each patient out for the covariate summaries; by default estimation has already left out any patient who moved one by 15 or more.

Usage

model_privacy_checks(fitted_model)

Arguments

fitted_model

A pmx_fitted_model from synpmx_model_estimate(), or a fingerprint from model_fingerprint(). A fingerprint carries only the verdict of the fifth check; the full fit carries the table behind it.

Value

A pmx_privacy_checks data frame with columns check, question, result, criterion and verdict. On a full fit, the reading behind P5 is the influence attribute, one row per released estimate with the released value, the largest move one patient causes, its unit and its verdict; and the recount behind P4 is the frequencies attribute, one row per kind of released frequency with the smallest group behind it, its floor and how many values were changed to meet it. No row is about a patient.

Details

None of this is a formal privacy guarantee. The fifth check describes this study only, and an adversary who knows every other patient in it can detect a move smaller than any threshold. The article Privacy protections in the PMX model generator states what each check establishes and what it does not.