ENCePP Guide on Methodological Standards in Pharmacoepidemiology

What it is

— The ENCePP Guide on Methodological Standards in Pharmacoepidemiology (commonly the "ENCePP Guide") is a living, web-published reference maintained by the European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCePP), a scientific network coordinated by the European Medicines Agency (EMA). First issued in 2010 and now at Revision 11 (July 2023), it is organized into chapters that point to authoritative methodological references across the full study lifecycle — research-question formulation, study design, data sources and their fitness, exposure/outcome/covariate definition, statistical analysis, bias and confounding control, and reporting. Critically, it is a curated standards-and-references guide, not an item-by-item checklist or scoring instrument: it tells you where the methodological consensus sits and which tools to use, but the operational fill-in artifacts are its companions — the ENCePP Checklist for Study Protocols (a protocol completeness aid) and the ENCePP Code of Conduct (governance, transparency, and independence). It sits alongside, and explicitly cross-references, reporting guidelines (STROBE, RECORD/RECORD-PE) and protocol templates (STaRT-RWE, HARPER) rather than replacing them.

When to use

— Reach for the ENCePP Guide whenever you are designing, conducting, or appraising a non-interventional or hybrid pharmacoepidemiology study intended for an EMA regulatory pathway, an HTA/payer dossier, or a peer-reviewed journal — especially studies on routinely collected data (claims, EHR, registries, linked/multi-database). It is the default European reference for post-authorisation safety studies (PASS), both imposed (a condition of marketing authorisation, governed by GVP Module VIII) and voluntary, and for drug-utilization, comparative-safety, and comparative-effectiveness work. Decision rule for which document to open: use the Guide to choose and justify methods; use the ENCePP Checklist for Study Protocols to confirm your protocol documents the required design choices; use STaRT-RWE or HARPER when you need a structured template to specify the study; and use STROBE / RECORD-PE when you reach the reporting stage. For systematic reviews/meta-analyses, the Guide is not the right home — use PRISMA-family guidance instead.

What it requires

— Although not a checklist, the Guide enforces a substantive set of methodological expectations that map directly onto real-world-data practice: (1) an explicit research question and PICOTS/estimand framing — target population, treatment strategies, intercurrent-event handling, and the causal contrast; (2) documented data fitness-for-purpose — provenance, capture, lag, completeness, and relevance of each source, with payer-specific caveats (e.g., Medicare fee-for-service vs Advantage capture); (3) validated phenotype/algorithm definitions for exposure, outcomes, and covariates, with reported operating characteristics (PPV/sensitivity); (4) time-zero alignment that emulates an eligibility-and-assignment moment and avoids immortal time; (5) rigorous confounding control (active-comparator/new-user design, high-dimensional propensity scores, negative controls); (6) transparent handling of attrition, missing data, and competing risks; and (7) pre-specified sensitivity and quantitative bias analyses (E-value, probabilistic bias analysis, empirical calibration) with versioned code lists and analysis specifications. Underlying all of it: transparency, registration (the EU PAS Register / HMA-EMA Catalogues), and scientific independence per the Code of Conduct.

When NOT to use — limitations and common misapplications

— The most frequent error is treating the Guide as a fill-in template or a quality score. It is neither. (a) It is not a reporting checklist — "we followed the ENCePP Guide" does not satisfy STROBE or RECORD-PE reporting requirements, and reviewers should ask for the actual reporting checklist. (b) It is not a risk-of-bias instrument — it does not yield a graded bias judgment the way ROBINS-I does; do not cite it as evidence that a study is low-bias. (c) Confusing the three ENCePP artifacts — the Guide (standards reference), the Checklist for Study Protocols (protocol completeness), and the Code of Conduct (governance) are distinct; submitting one when another is expected is a common regulatory friction point. (d) Checklist-as-theater — completing the protocol checklist or asserting Guide adherence does not make an observational study causal; the design and analysis still have to earn the causal interpretation. (e) Wrong tool for the job — using the Guide for systematic-review reporting (use PRISMA) or for interventional-trial reporting (use CONSORT) is a category error. (f) The Guide is maintained and versioned — citing a stale revision or a broken chapter link undermines an EMA submission; always confirm the current revision and the live URL.

How it maps to this catalog

— Each Guide expectation is implemented by a concept in this repository. Research question, estimand, and intercurrent events → `picots-framework-rwe` and `estimands-ate-att-intercurrent-events-rwe`; protocol/SAP structure → `study-protocol-or-sap-elements`. Data fitness → `fit-for-purpose-data-assessment-rwe`, with claims operational detail in `claims-analysis` and `continuous-enrollment-observable-time-rwe`. Phenotype/algorithm validation → `diagnosis-phenotype-algorithm-1ip-2op-time-window-rwe`, `claims-outcome-algorithm-ppv-sensitivity-rwe`, and `algorithm-validation`. Time-zero and immortal time → `time-zero-index-date-alignment-rwe`, `washout-clean-lookback-period-rwe`, and `immortal-time-bias-handling`. Design and confounding control → `active-comparator-new-user`, `high-dimensional-propensity-score-hdps-rwe`, `target-trial-emulation`, and `empirical-calibration-negative-controls-rwe`. Attrition, competing risks, and sensitivity → `attrition-and-loss-to-follow-up-rwe`, `competing-risks-cause-specific-fine-gray-rwe`, `e-value-sensitivity-analysis`, and `quantitative-bias-analysis-toolkit-rwe`. Regulatory packaging for PASS → `regulatory-readiness-rwe`, `pass-imposed`, and `pass-voluntary`. Applied note (claims/EHR/registry RWE): for a claims-based imposed PASS, treat the Guide as the spine of the protocol — pre-register on the EU PAS Register, specify the active-comparator new-user cohort with a 365-day continuous-enrollment washout, validate the outcome phenotype (report PPV), align time zero at first qualifying fill, build a high-dimensional propensity score from the baseline window, and pre-specify a CONSORT-style attrition flow plus E-value/negative-control sensitivity analyses — then report against RECORD-PE.