Skills

Detecting Pv Signals

Computes disproportionality signals, PRR, ROR, EBGM, and IC (BCPNN), over FAERS /...

Install

npx skills add maziyarpanahi/openmed --skill detecting-pv-signals -g -a claude-code -y
Repository
maziyarpanahi/openmed5.8k
Category
Engineering
Updated
4d ago
License
Apache-2.0
Context cost
Mediumabout 2,076 tokens
Runs scripts
No, instructions only

What it does

Computes disproportionality signals, PRR, ROR, EBGM, and IC (BCPNN), over FAERS / OpenFDA drug-event data to flag potential safety signals. Use when the user wants to mine spontaneous-report data for drug-reaction associations, build a 2x2 contingency table, compute a Proportional Reporting Ratio or Reporting Odds Ratio, run Empirical Bayes (EBGM/EB05) or Information Component shrinkage, or screen a drug for over-reported reactions. Trigger keywords: disproportionality, signal detection, PRR, ROR, EBGM, EB05, IC, BCPNN, MGPS, 2x2 table, signal of disproportionate reporting, SDR, OpenFDA, FAERS. Pairs adjacent to OpenMed: aggregate de-identified, coded cases (from reporting-adverse-events) then query the public OpenFDA /drug/event count API to build the contingency table. Reaction terms are MedDRA PTs (licensed, user-supplied).

Detecting pharmacovigilance signals (disproportionality)

Spontaneous-report databases like the FDA's FAERS are mined for signals of disproportionate reporting (SDR): drug-reaction pairs that occur together more than expected given the background of all reports. The core device is a 2x2 contingency table and a disproportionality metric computed from it, PRR, ROR, EBGM, or IC (BCPNN).

You can build the 2x2 table directly from the public, free OpenFDA /drug/event endpoint (no PHI, no MedDRA license to query; the reaction terms returned are already MedDRA PTs). This skill is statistical screening: a high PRR is a hypothesis, not a confirmed adverse drug reaction.

When to use

  • You have a drug of interest and want to see which reactions are over-reported.
  • You need a PRR / ROR with confidence interval, or an Empirical Bayes EBGM/EB05 / IC025 to control for the small-count noise PRR/ROR suffer from.
  • You are building a routine signal-screening run over OpenFDA or your own aggregated case counts.

The 2x2 table

For one drug D and one reaction R, classify every report:

Reaction RNot R
Drug Dab
Not Dcd
  • PRR = [a/(a+b)] / [c/(c+d)]
  • ROR = (a·d)/(b·c)
  • IC (BCPNN, log2 information component) ≈ log2( a·(a+b+c+d) / ((a+b)·(a+c)) )
  • EBGM = Empirical Bayes Geometric Mean, a gamma-Poisson shrinkage of the observed/expected ratio (the MGPS method) that pulls small-count estimates toward 1; report EB05 (the 5th percentile) as the conservative signal.

Common signal thresholds (screening only): PRR ≥ 2 with χ² ≥ 4 and a ≥ 3; ROR lower 95% CI > 1; IC025 > 0; EB05 ≥ 2.

Quick start (real OpenFDA count queries)

Read the whole SKILL.md on GitHub

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