Clinical research glossary

The terms behind modern patient data collection

Short, citeable definitions of the concepts we work with every day — written for patient-advocacy leaders, academic PIs, and research operations teams. Use the anchor links to cite a specific entry.

Validated Surveys Also known as: Validated patient-reported outcome measures · Validated PRO instruments: Validated surveys are patient-reported questionnaires whose psychometric properties (reliability, validity, responsiveness) have been established in published research. They produce regulatory-grade endpoints but can suffer from survey fatigue and recall bias when administered repeatedly.; Common examples include PROMIS, SF-36, EQ-5D, QOLIE-31 (epilepsy), MIDAS and HIT-6 (migraine), and BPI (pain). Forma Health delivers validated surveys on protocol-defined schedules while capturing real-time ecological data in between.
ePRO Also known as: Electronic Patient-Reported Outcomes · Electronic PRO · Electronic patient-reported outcome measures: ePRO (electronic patient-reported outcomes) is the digital capture of a patient's own report of their health status — symptoms, function, quality of life — without clinician interpretation, typically via smartphone, tablet, or web form.; ePRO replaces paper diaries in clinical trials and is FDA-accepted when instruments are validated and audit trails meet 21 CFR Part 11. Forma Health is an ePRO platform that extends beyond scheduled assessments to capture continuous real-time patient data.
Survey Fatigue Also known as: Respondent fatigue · Questionnaire fatigue: Survey fatigue is the decline in response quality and completion rate that occurs when patients are asked to complete too many questionnaires over time. It is one of the largest drivers of missing data in long-running clinical studies and registries.; Symptoms of survey fatigue include straight-lining responses, dropout, and degraded signal-to-noise ratios in efficacy analyses. Forma Health mitigates survey fatigue with brief, context-aware event logging rather than repeated long-form questionnaires.
Patient Journal Also known as: Patient diary · Symptom diary · Health diary: A patient journal is a self-kept record of symptoms, events, medications, and triggers. Traditional paper journals suffer from recall bias and parking-lot completion; digital journals like Forma Health capture entries in the moment with timestamps, medication linkage, and structured fields suitable for research.
Real-World Evidence (RWE) Also known as: Real World Evidence: Real-world evidence (RWE) is clinical evidence derived from real-world data (RWD) about the usage and potential benefits or risks of a medical product. RWE supports regulatory decisions, label expansions, payer negotiations, and post-market surveillance.; The FDA's RWE framework (21st Century Cures Act) recognizes ePRO, patient registries, EHRs, and claims as RWD sources. Forma Health contributes prospectively collected, patient-reported RWD with full audit trails, making it suitable for RWE programs in rare disease, natural history, and label-expansion contexts.
Real-World Data (RWD) Also known as: Real World Data: Real-world data (RWD) is data relating to patient health status or the delivery of healthcare routinely collected from a variety of sources outside of traditional randomized controlled trials — including EHRs, claims, patient registries, patient-reported data, and wearable devices.; High-quality RWD is structured, longitudinal, and traceable. Forma Health produces prospectively collected, patient-reported RWD at high temporal resolution, complementing retrospective RWD sources like EHRs and claims.
Patient Registry Also known as: Disease registry · Clinical registry: A patient registry is an organized system that collects uniform data on a defined patient population (by disease, exposure, or procedure) for scientific, clinical, or policy purposes. Registries underpin natural history studies, real-world evidence generation, and rare disease research.; Effective registries require consistent data capture, long-term patient engagement, and structured outputs suitable for downstream analysis. Forma Health provides registry-grade data collection with condition-specific templates, longitudinal retention features, and research-ready data exports.
Natural History Study: A natural history study is a longitudinal observational study that describes the course of a disease — onset, progression, variability, and outcomes — in the absence of a specific intervention. Natural history studies are foundational for rare disease drug development and for designing future interventional trials.
Ecological Momentary Assessment (EMA) Also known as: Experience sampling · Ambulatory assessment: Ecological momentary assessment (EMA) is a research method that captures patient-reported data in the moment, in a patient's natural environment, multiple times per day. EMA reduces recall bias and reveals intra-day variability that weekly or monthly surveys miss.; Forma Health is built for EMA workflows: short, context-aware prompts (vs. long questionnaires) with timestamping, GPS/activity context where consented, and linkage to event logs and medication timing.
Decentralized Clinical Trial (DCT) Also known as: Virtual trial · Remote clinical trial · Hybrid trial: A decentralized clinical trial (DCT) conducts some or all trial activities remotely — outside traditional clinical sites — using digital technologies, telehealth, home visits, and ePRO. DCTs broaden access, improve retention, and enable real-world data capture at scale.

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The terms behind modern patient data collection

Validated Surveys

ePRO

Survey Fatigue

Patient Journal

Real-World Evidence (RWE)

Real-World Data (RWD)

Patient Registry

Natural History Study

Ecological Momentary Assessment (EMA)

Decentralized Clinical Trial (DCT)

See these concepts in a real study configuration