Utforsk vitenskapen etter metode, felt og evidens.

Prospective Dose-Response Analysis

Prospective dose-response analysis is an epidemiological approach that measures exposure levels in a defined population before outcomes occur, then quantifies how the risk or magnitude of an outcome changes systematically as exposure increases. By collecting exposure data prospectively, researchers can establish tempor

2 kilder1965

Prospective Ecological Study

A prospective ecological study is an observational epidemiological design in which groups — not individuals — serve as the unit of analysis, and exposure data are collected going forward in time before outcomes are measured. Investigators define geographically, politically, or socially bounded populations, characterise

Prospective Nested Case-Control

A prospective nested case-control study enrolls a cohort before disease onset, follows participants forward in time, and then — once cases develop — samples matched controls from those still at risk at the time each case occurs. By embedding the case-control comparison inside a prospective cohort, the design combines t

2 kilder1977

Prospective Phase IV Study

A prospective Phase IV study is a post-marketing investigation conducted after a drug, device, or intervention has received regulatory approval, following participants forward in real time to collect safety, effectiveness, and utilization data under routine clinical practice conditions. Unlike retrospective designs tha

2 kilder1970

Prospective Randomized Clinical Trial

A prospective randomized clinical trial (RCT) is an experimental study in which participants are assigned to intervention or control groups by chance before any outcomes are observed, then followed forward in time. Random allocation eliminates systematic selection bias, making this design the gold standard for establis

2 kilder1948

Prospective Screening Test Evaluation

A prospective screening test evaluation enrolls participants before the outcome is known, applies the screening test and the reference standard in temporal sequence, and measures how accurately the test identifies individuals with or without the target condition. This forward-looking design minimizes workup bias and sp

2 kilder1980

Prospective Survival Analysis

Prospective survival analysis is a longitudinal study design in which participants are enrolled before the event of interest occurs, followed forward in time under standardised conditions, and analysed using survival-analytic methods to estimate the time until a defined clinical endpoint — such as death, disease recurr

2 kilder1958

dermatology

Pruritus VAS

The Pruritus Visual Analog Scale (VAS) is a simple, single-item patient-administered tool measuring itch intensity on a continuous 0–10 (or 0–100) scale. Adapted from the original VAS for pain, it is one of the most frequently used outcome measures in dermatological research and clinical practice due to its simplicity,

2 kilder1983

health education

PSCS

The PSCS is a self-report instrument measuring healthcare students' and professionals' self-perceived competence in patient safety practices, safety awareness, and safety culture engagement. Developed by Lachman and informed by James Reason's theoretical framework of human error and systems thinking, the PSCS evaluates

2 kilder2012

PSUS

The PSUS is a self-report questionnaire measuring compulsive smartphone use, withdrawal symptoms, and loss of control related to mobile devices. Developed by Hussain, Griffiths, and Sheffield in 2017, it targets the growing phenomenon of smartphone addiction in the digital age. The PSUS captures how smartphone dependen

3 kilder2017

occupational health

Psychosocial Safety Climate Scale

The Psychosocial Safety Climate Scale (PSC-12) measures employees' perceptions of organizational commitment to protecting worker psychological health and preventing psychosocial hazards (stress, harassment, bullying). Developed by Dollard and Karasek, and refined by Bailey and colleagues, the PSC-12 captures four dimen

2 kilder2010

psychiatric rehabilitation

PTSD Checklist for DSM-5

The PTSD Checklist for DSM-5 (PCL-5) is a 20-item self-report measure of posttraumatic stress disorder (PTSD) symptoms aligned with DSM-5 diagnostic criteria. Developed by Weathers, Litz, and Keane, it is the gold standard screening and outcome measure for PTSD in military, veteran, and civilian trauma populations. The

2 kilder2013

pediatric medicine

QOLCE

The QOLCE is a comprehensive 76-item disease-specific instrument developed by Sabaz et al. in 2000 to assess quality of life in children with epilepsy aged 4–16 years. Measuring across 16 distinct domains including seizure worry, cognitive concerns, medication effects, school/peer functioning, and family impact, the QO

2 kilder2000

neurology

QOLIE-89

The QOLIE-89 is a comprehensive disease-specific quality-of-life instrument developed specifically for people with epilepsy. Introduced by Devinsky and colleagues in 1995, it captures the broad impact of epilepsy on physical, emotional, social, and cognitive functioning. With 89 items organized into 17 distinct domains

1 kilde1995

clinical assessment

qSOFA Score

The Quick Sequential Organ Failure Assessment (qSOFA) score, introduced by the Sepsis-3 taskforce in 2016, is a rapid 3-variable bedside screening tool for identifying non-ICU patients at high risk of sepsis-related mortality. It uses altered mentation, systolic hypotension, and tachypnea to quickly stratify patients w

2 kilder2016

addiction medicine

QSU-Brief

The QSU-Brief is a 10-item self-report instrument that rapidly assesses the intensity of craving for cigarettes and the intention to smoke. Developed by Cox, Tiffany, and Christen in 1996, it is a brief version of the longer Questionnaire on Smoking Urges (QSU) and is widely used in smoking cessation treatment and rese

1 kilde1996

health economics

Quality-Adjusted Life Year

A QALY measures health benefit as utility weight (0 = death, 1 = perfect health) multiplied by time lived. Developed by Alan Williams in 1985, QALYs enable comparison of disparate health interventions on a common metric. Used globally by health technology assessment bodies—NICE (UK), HAS (France), CADTH (Canada), WHO—t

3 kilder1985

Questionnaire about the Process of Recovery

The Questionnaire about the Process of Recovery (QPR), also called the 'Neil-QPR,' is a 22-item self-report measure assessing subjective recovery processes in individuals with serious mental illness, particularly schizophrenia and related disorders. Developed by Stephen T. Neil, Matthias Kilbride, Leonie Pitt, and coll

1 kilde2009

healthcare management

Queuing Theory in Healthcare

Queuing theory is a mathematical discipline that models waiting lines, service capacity, and customer (patient) flow. Developed initially by Agner Erlang for telecommunications in 1909, it has been extensively applied to healthcare to analyze and optimize emergency departments, outpatient clinics, surgical suites, and

3 kilder1909

Quick Inventory of Depressive Symptomatology

The Quick Inventory of Depressive Symptomatology is a 16-item assessment designed by A. John Rush and colleagues to efficiently measure the severity of depressive symptoms in adults. Published in Biological Psychiatry in 2003, the QIDS exists in both self-report (QIDS-SR) and clinician-rated (QIDS-C) versions. It was d

3 kilder2003

health outcomes

RA-QoL

The RA-QoL is a disease-specific quality of life measure for rheumatoid arthritis (RA). Developed by Stephen McKenna and colleagues in 1997, this 30-item questionnaire quantifies how RA affects daily activities, emotional well-being, functional independence, and social engagement. It is a standard outcome measure in RA

3 kilder1997

transcultural nursing

Racism and Life Experiences Scales

The Racism and Life Experiences Scales (RaLES) are a multidimensional assessment designed to measure the frequency and intensity of racism-related stress experienced by people of color. Developed by Harrell in 2000, the RaLES operationalize racism not as a single phenomenon but as a constellation of stressors across mu

1 kilde2000

veterinary medicine

Radiographic Assessment in Veterinary Medicine

Radiographic assessment is a systematic diagnostic imaging method using X-rays to create two-dimensional images of internal structures, facilitating detection of skeletal, thoracic, and abdominal pathology. Since the discovery of X-rays in 1896 and their early adoption in veterinary medicine, radiography has remained f

3 kilder1896

survival

Random Survival Forest

Random Survival Forest (RSF), introduced by Ishwaran, Kogalur, Blackstone, and Lauer in 2008, is an ensemble machine learning method that adapts the Random Forest algorithm to time-to-event (survival) data. Trees are grown using log-rank splitting to handle censored observations naturally, and the ensemble aggregates c

1 kilde2008

psychiatric rehabilitation

Randomized clinical trial

A randomized clinical trial (RCT) is an experimental study design in which participants are randomly assigned to an intervention group or a control group, then followed prospectively to compare outcomes. Random allocation is the defining feature: it distributes known and unknown confounders across groups by chance, mak

2 kilder1948

physical therapy

Range of Motion Goniometry

Goniometry is the standardized clinical measurement of joint angles using a goniometer (angle-measuring instrument) to quantify range of motion in degrees. Developed from orthopedic assessment traditions, goniometric measurement is a fundamental skill in physical therapy, occupational therapy, and orthopedic medicine f

2 kilder1960

addiction medicine

RCQ

The RCQ is a 12-item self-report instrument designed to assess an individual's stage of change motivation regarding substance use, particularly alcohol use. Developed by Rollnick and colleagues in 1992, it operationalizes the Transtheoretical Model of Change by measuring readiness across the precontemplation, contempla

1 kilde1992

implementation science

RE-AIM Framework

The RE-AIM framework (Reach, Effectiveness, Adoption, Implementation, Maintenance) is a five-dimension evaluation tool designed to assess the public health impact of evidence-based interventions in real-world settings. Developed by Glasgow et al. (1999) to address the gap between efficacy trials (controlled conditions)

3 kilder1999

clinical research

Real-World Evidence Studies

Real-World Evidence (RWE) is clinical evidence derived from Real-World Data (RWD)—data routinely collected in clinical practice from electronic health records, insurance claims, patient registries, and other healthcare sources. Formalized by the FDA in 2016 (Sherman et al.), RWE addresses a critical gap: while randomiz

3 kilder2010

Recovery Assessment Scale

The Recovery Assessment Scale (RAS) is a 41-item self-report measure designed to assess personal recovery in individuals with serious mental illness. Developed by Corrigan and colleagues in 2004, it captures the subjective and multidimensional nature of recovery, including hope, autonomy, goal achievement, and symptom

1 kilde2004

occupational health

Recovery Experience Questionnaire

The Recovery Experience Questionnaire (REQ) is an assessment tool measuring the quality and dimensions of off-work recovery from occupational stress. Developed by Sonnentag and Fritz in 2007, the REQ evaluates four key recovery experiences: psychological detachment from work, relaxation, mastery, and control. The instr

1 kilde2007

psychiatric rehabilitation

Recovery-Oriented Practices Index

The Recovery-Oriented Practices Index (ROPI) is a measure assessing the degree to which mental health services and programs embody recovery-oriented principles and practices. Developed by Sanja P. Barbic, Trevor Krupa, and Inge Armstrong in 2009, the ROPI evaluates whether services prioritize consumer choice, hope, aut

1 kilde2009

survival

Recurrent Event Model

A recurrent event model is a survival analysis extension, formalised through the landmark contributions of Prentice, Williams and Peterson (1981), Andersen and Gill (1982), and Wei, Lin and Weissfeld (1989), that models time-to-event data when the same event — such as a hospital readmission, disease relapse, or equipme

2 kilder1981

clinical research

Registry-Based Research

Registry-based research uses systematically collected clinical data from patient registries—organized databases of patients with a specific disease or condition—to conduct observational studies. Registries began in the mid-20th century but have proliferated since the 2000s as electronic health records expanded and fund

3 kilder2000

rehabilitation science

Reintegration to Normal Living Index

The Reintegration to Normal Living Index (RNLI) is a brief, patient-report measure designed to assess how completely a person has returned to 'normal' community living following a major health event (stroke, head injury, cardiac event, or other condition requiring significant recovery). Developed by Wood-Dauphinee and

2 kilder1988

Rejection Sensitivity Questionnaire

The RSQ is an 18-item self-report measure of rejection sensitivity—the disposition to anxiously expect, readily perceive, and intensely react to rejection from others. Developed by Downey and Feldman in 1996, it captures both anxiety about rejection and expectancy of rejection. Rejection sensitivity is recognized as tr

1 kilde1996

Reproduction Number

The basic reproduction number R0 is the expected number of secondary infections produced by a single infectious individual introduced into a fully susceptible population. Formally defined and computationally grounded by Diekmann, Heesterbeek, and Metz in 1990 using the next-generation matrix approach, R0 serves as the

1 kilde1990

Retrospective Case Report

A retrospective case report is a detailed, structured narrative of a single patient's clinical presentation, diagnosis, management, and outcome, assembled from existing medical records after the clinical events have occurred. It is the most granular and accessible observational design in clinical medicine, serving prim

2 kilder2013

Retrospective Case Series

A retrospective case series is an observational study that systematically describes the clinical features, treatments, and outcomes of a defined group of patients by examining pre-existing medical records or administrative data. It looks backward in time — data have already been recorded before the study begins. With n

2 kilder1990

Retrospective case-control study

A retrospective case-control study identifies individuals who already have an outcome of interest (cases) and a comparable group without it (controls), then looks backward in time using existing records to determine prior exposure to a suspected risk factor. The primary measure of association is the odds ratio. This de

Retrospective Cohort Study

A retrospective cohort study assembles a group of individuals who share a common starting point and reconstructs their exposure history and subsequent outcomes entirely from pre-existing records. Because the data have already been collected before the study begins, the design is far faster and cheaper than a prospectiv

Retrospective competing risks analysis

Retrospective competing risks analysis applies competing risks methodology to historical (already-collected) time-to-event data in which subjects can experience one of several mutually exclusive endpoints. It uses the cumulative incidence function and cause-specific or subdistribution hazard models to estimate the prob

2 kilder1978

Retrospective Cox proportional hazards

Retrospective Cox proportional hazards regression applies Cox's (1972) semi-parametric survival model to time-to-event data extracted from existing records — medical charts, administrative databases, registries, or biobanks. It estimates covariate-adjusted hazard ratios (HRs) without specifying the underlying baseline

2 kilder1972

Retrospective cross-sectional epidemiological study

A retrospective cross-sectional epidemiological study measures the prevalence of exposures and outcomes at a single analytical time point using data that were originally recorded in the past — such as medical records, administrative databases, or disease registries. It combines the snapshot logic of a cross-sectional d

2 kilder

Retrospective diagnostic accuracy study

A retrospective diagnostic accuracy study evaluates how well a diagnostic test (the index test) correctly identifies a target condition by applying it to previously collected data or archived specimens alongside a reference standard. Because both index test results and reference standard results are drawn from existing

2 kilder2000

Retrospective Ecological Study

A retrospective ecological study examines associations between exposures and outcomes using pre-existing aggregate data from defined populations or geographic units. Rather than following individual subjects, the unit of analysis is a group — a country, region, or time period — and all measurements come from historical

2 kilder1980

Retrospective Kaplan-Meier Analysis

Retrospective Kaplan-Meier analysis applies the Kaplan-Meier product-limit estimator to time-to-event data drawn from existing records — medical charts, registries, or administrative databases — rather than from a prospectively followed cohort. The method estimates the probability of surviving (or remaining event-free)

2 kilder1958

Retrospective nested case-control

A retrospective nested case-control study is an efficient observational design in which cases and matched controls are sampled from within an already-assembled retrospective cohort. Exposure data are retrieved from historical records only for selected participants, dramatically reducing data-collection costs while reta

2 kilder1973

Retrospective phase II clinical trial

A retrospective Phase II clinical trial evaluates a treatment's preliminary efficacy and safety signals using existing archival data — medical records, registries, or electronic health records — rather than prospectively enrolling new patients. It mirrors the objectives of a standard Phase II trial (estimating response

2 kilder1980

Retrospective phase III clinical trial

A retrospective Phase III clinical trial evaluates the comparative efficacy and safety of an intervention against a control using data that were collected before the study was designed. Rather than enrolling new patients prospectively, researchers analyze existing records — from registries, hospital databases, or histo

2 kilder1997

Retrospective survival analysis

Retrospective survival analysis applies time-to-event statistical methods — most commonly the Kaplan-Meier estimator and Cox proportional hazards regression — to data collected from past records rather than through prospective follow-up. The researcher looks back at medical records, disease registries, or administrativ

2 kilder1970

clinical assessment

Richmond Agitation-Sedation Scale

The Richmond Agitation-Sedation Scale (RASS), developed by Sessler et al. in 2002, is a 10-level ordinal scale for assessing level of consciousness, agitation, and sedation in critically ill patients. It ranges from +4 (combative/violent) through 0 (alert and calm) to -5 (unarousable), enabling precise titration of sed

2 kilder2002

health education

RIPLS

The RIPLS is a 19-item self-report questionnaire designed to measure healthcare students' attitudes and readiness toward interprofessional learning and collaboration. Developed by Parsell and Bligh in 1999, it assesses three core dimensions of interprofessional readiness: teamwork and collaboration, professional identi

1 kilde1999

Risk-adjusted case series

A risk-adjusted case series is an observational study design that reports outcomes for a consecutive or defined group of patients undergoing the same procedure or sharing a condition, while statistically correcting for differences in patient-level baseline risk. Rather than presenting raw complication or mortality rate

2 kilder1990

Risk-adjusted case-control study

A risk-adjusted case-control study is an observational design that identifies individuals with a disease outcome (cases) and comparable individuals without it (controls), then uses statistical adjustment — most commonly multivariable logistic regression — to estimate the association between an exposure and the outcome

Risk-adjusted case-crossover design

The risk-adjusted case-crossover design is a self-matched epidemiological method that compares a person's exposure during a brief hazard window immediately preceding an acute event to their exposure during one or more control windows from the same individual, while formally accounting for time-varying or time-fixed cov

2 kilder1991

Risk-adjusted cohort study

A risk-adjusted cohort study is an observational epidemiological design in which a defined group of individuals is followed over time to compare outcomes between exposed and unexposed subgroups, with statistical methods applied to control for measured confounders. Adjustment strategies — including multivariable regress

2 kilder1970

Risk-adjusted competing risks analysis

Risk-adjusted competing risks analysis extends classical survival analysis to settings where subjects can experience more than one type of terminal event, and where the occurrence of one event prevents the occurrence of another. By modelling cause-specific or subdistribution hazards while adjusting for measured confoun

2 kilder1999

Risk-adjusted Cox Proportional Hazards

Risk-adjusted Cox proportional hazards regression extends the classical Cox (1972) survival model by simultaneously entering known confounders — age, sex, comorbidities, disease severity — into the model alongside the exposure of primary interest. This adjustment isolates the independent effect of the exposure on the h

2 kilder1972