See suffering more clearly - and act where it may matter most

World Suffering Index transforms public data on diseases, disasters, displacement, and other documented harms into clear, comparable evidence about human suffering.

It is powered by Universal Suffering Units (USU) - a new measurement framework that combines how intense an experience is, how long it lasts, and how many people are affected. Each WSI series applies the same source, definitions, and USU method across eligible locations.

The goal is to help governments, funders, public-health agencies, and humanitarian organizations identify large burdens, compare priorities more consistently, and track whether action reduces suffering over time.

A common unitUSU combines intensity, duration, and people affected Harmonized evidenceThe same source and rules across eligible locations Built for actionTotal, per-capita, severity, and uncertainty

Why quantify suffering?

Governments, researchers, funders, and humanitarian organizations routinely compare very different harms. Yet disease outbreaks, disasters, displacement, and food insecurity are reported in different units - cases, people affected, severity categories, days displaced, or deaths.

WSI adds a common experiential perspective. It does not erase the original data; it helps show how the intensity and duration of an experience combine with the number of people affected.

01

See beyond counts

Distinguish between harms that affect many people briefly and harms that affect fewer people more intensely or for longer.

02

Compare places consistently

Apply one source, one reporting period, and one model across all eligible countries, territories, or events.

03

Support better priorities

Give public-health, humanitarian, and philanthropic decisions another evidence-based view of where burden is concentrated.

04

Build a growing evidence library

Create a growing collection of comparable series that can be updated and extended over time.

What is a Universal Suffering Unit?

A Universal Suffering Unit (USU) is a calibrated way to combine how intense a negative experience is, how long it lasts, and how many people experience it.

The scale is anchored so that one specified, stylized trajectory of renal-colic pain equals 1.0 USU. The anchor gives different modeled experiences a common reference while keeping the calibration and assumptions visible.

WSI uses USU as one additional perspective alongside case counts, mortality, DALYs, QALYs, and operational humanitarian indicators - not as a replacement for them.

IntensityHow bad is the experience?
DurationHow long does it last?
PeopleHow many are affected?
Modeled suffering burdenReported with uncertainty

Comparing reported dengue burden across the Americas

Official surveillance already reports dengue cases, severe cases, incidence, and deaths. Those figures are essential, but each tells only part of the story.

A WSI dengue series will apply the same illness profiles and uncertainty model to every eligible location in the same reporting system. It will then show both the total modeled suffering associated with reported cases and the burden relative to population size.

The country with the greatest total burden may not be the country with the greatest burden per 100,000 people. Severity composition can also change the comparison. WSI makes these distinctions easier to see while keeping the original surveillance data visible.

Long-term potential: As the series library grows, the same framework could support careful comparisons between different well-documented states - such as dengue, acute food insecurity, and disaster-related displacement - using the same common unit.

1
Official dengue dataCases, severe cases, population, and deaths
2
One common burden modelShared intensity, duration, and uncertainty assumptions
Total burdenWhere is the largest aggregate burden?
Per-capita burdenWhere is burden most concentrated?
Severity and uncertaintyHow robust is the comparison?

How a WSI Comparative Burden Series is built

WSI lets the availability of strong, harmonized data guide which comparisons are feasible. Each analysis then follows the same clear sequence.

  1. 1

    Choose one well-documented condition or event

    Define the research question, time period, geography, and eligible source universe before calculating results.

  2. 2

    Use a harmonized public data source

    Retain the original counts and classifications, reconcile units, and distinguish reported zero from missing or unavailable data.

  3. 3

    Add the experiential dimension

    Use Universal Suffering Units to represent how intensity, duration, and population scale combine for each documented state.

  4. 4

    Estimate burden and uncertainty

    Calculate total and per-capita burden, severity composition, uncertainty intervals, and the stability of comparative rankings.

  5. 5

    Publish a clearly documented release

    Present the scope, source references, assumptions, results, sensitivity analyses, and version information together.

A growing collection of focused global comparisons

WSI will begin with topics for which a common source and a defensible suffering-state model can support meaningful comparisons.

Planned research series

Acute food insecurity

A comparative series based on harmonized food-insecurity severity classifications, designed to show both the number of people affected and the distribution across severity phases.

Planned research series

Disaster-related displacement

A comparative series examining documented displacement associated with disasters, with attention to duration, living conditions, and the difference between movements and displaced populations.

Results designed to be clear and actionable

Every completed WSI series will pair an accessible comparison with clear documentation of the data sources, methods, assumptions, and uncertainty behind the results.

Total modeled burdenThe aggregate burden associated with the documented state.
Burden per 100,000A population-adjusted view of where burden is most concentrated.
Severity compositionHow much of the burden comes from different documented severity levels.
Uncertainty and ranking stabilityIntervals and probability-based views when exact ordering is uncertain.
Mortality shown separatelyDeaths remain visible rather than being silently folded into experienced suffering.
Methods and provenanceSource coverage, definitions, assumptions, methodology, and release version.

Understanding the purpose, method, and future of WSI

WSI turns existing public data into focused comparisons of documented suffering. USU supplies the common intensity-over-time framework; each WSI series supplies the specific data, scope, and evidence needed for a useful comparison.

Purpose and practical use

1. How could WSI be used in practice?

WSI can help public-health agencies, humanitarian organizations, researchers, and funders compare the scale and concentration of documented suffering within a well-defined topic.

It can support prioritization, track changes over time, highlight severe or under-recognized burdens, improve public communication, and reveal where better data are needed. WSI is designed to inform judgment - not replace it.

2. What are WSI and USU for?

WSI is the applied research project: it produces harmonized comparative burden series for specific diseases, humanitarian conditions, and events.

USU is the underlying measurement framework: it combines modeled intensity, duration, and the number of people affected on a common calibrated scale.

3. Why use a kidney-stone episode as the 1.0 USU anchor?

Renal colic is intense, time-bounded, commonly assessed on clinical pain scales, and supported by published pain and treatment-response data. A specified, stylized renal-colic trajectory is defined as 1.0 USU.

This is a calibration convention, not a claim that kidney-stone pain is the most important form of suffering. Because the calibration is explicit, alternative anchors can be tested and results can be rescaled.

4. Why not measure pain alone?

Physical pain is only one form of suffering. Severe negative experience can also involve breathlessness, nausea, fatigue, panic, fear, grief, humiliation, or disruption of basic life conditions.

USU therefore targets experienced suffering more broadly. Pain provides the initial calibration anchor, but each non-pain state requires its own clear definition, evidence, and uncertainty.

5. Why not rely only on cases, deaths, or DALYs?

Case counts show how many episodes were reported, but not how intense or prolonged they were. Death counts are essential and remain separate. DALYs and QALYs are established health measures with different purposes.

WSI adds an experiential burden perspective and is intended to be used alongside - not instead of - those measures.

6. Why focus on one condition or event at a time?

A focused series can hold the source, definitions, time period, and burden model constant across all eligible locations. That makes the comparison much cleaner than adding a different mixture of available harms for every country.

Over time, many focused series can form a useful global evidence library and support country dashboards without forcing them prematurely into one total score.

Method, data, and interpretation

7. What will each WSI series report?

A completed series will report the source universe, reporting period, inclusion criteria, affected population or episode counts, total modeled burden, burden per 100,000, severity composition, uncertainty intervals, mortality indicators separately, and sensitivity analyses.

It will also document the source coverage, definitions, assumptions, methods, and release version.

8. How are total and per-capita burden different?

Total burden shows where the largest aggregate amount of documented suffering occurred. Per-capita burden shows where that burden was most concentrated relative to population size.

Both are useful, and they can produce different rankings. WSI will present them separately rather than blend them into one weighted score.

9. How are intensity and duration estimated?

Each state is defined as precisely as possible and linked to published evidence, clinical or humanitarian descriptions, validated measures, and clearly documented assumptions.

Intensity and duration are represented as ranges or probability distributions when uncertainty is meaningful. Observed source data remain separate from the modeled USU mapping.

10. Where do the data come from?

WSI will primarily use official public-health surveillance, humanitarian and disaster datasets, demographic sources, and peer-reviewed research.

Each comparative series will use a common source or harmonized source family and will identify the exact data snapshot and reporting cutoff used.

11. What does it mean when a country is absent from a series?

Absence does not mean absence of suffering. A location may fall outside the source coverage, use an incompatible reporting definition, or lack enough data for the specified period.

Every series will state its eligible universe and explain exclusions.

12. How does WSI handle uncertainty?

WSI will use probability distributions and Monte Carlo simulation where appropriate, reporting median estimates and uncertainty intervals rather than a single precise-looking number.

Shared assumptions - such as the duration of a disease state - will be sampled jointly across locations, while location-specific data uncertainty will be handled separately. When rankings are unstable, WSI can show rank probabilities or broad tiers.

13. How is psychological suffering represented?

Psychological suffering can be included when the state is clearly defined and supported by credible evidence or validated measures. Physical and psychological suffering are not assumed to be identical; they are compared through the narrower question of how negatively the state is experienced over time.

Any mapping for anxiety, depression, grief, trauma, or fear will be treated as context-specific and will require explicit uncertainty and validation.

14. How are overlapping harms handled?

WSI will not simply add separate series into a country total when the same people and time periods may overlap. Within analyses where co-occurring states matter, the overlap rule will be explicit and sensitivity-tested.

This allows multiple harms to be acknowledged without automatically counting the same experienced distress more than once.

15. How subjective is the method?

Any attempt to quantify experienced suffering involves judgment. WSI's goal is not to pretend otherwise, but to make the important choices visible: the anchor, state definition, intensity range, duration, overlap rule, and uncertainty.

Because the major assumptions and methods will be documented, researchers can examine how alternative choices might affect the conclusions.

16. What does WSI measure - and what remains separate?

WSI estimates experienced suffering associated with the specific states included in each series. It does not measure a person's worth, dignity, rights, productivity, or overall value of life.

Deaths and other mortality measures remain visible as companion outcomes rather than being automatically converted into experienced-suffering units.

17. How does WSI relate to DALYs, QALYs, HDI, and other indices?

DALYs and QALYs summarize health loss or health-adjusted time. HDI summarizes dimensions of human development. Other indices may combine economic, political, or security indicators.

WSI addresses a different question: how much modeled adverse experience is associated with a clearly defined condition or event across the locations included in one series. These measures can be used together because each reveals a different aspect of reality.

Future development and participation

18. Will WSI eventually publish an overall country ranking?

Possibly, but only after a sufficiently broad set of condition-specific series has comparable coverage and the effects of overlap and missing domains can be evaluated responsibly.

The condition-specific series are the immediate foundation. As coverage grows, WSI can test whether a broader country-level view becomes sufficiently comparable, stable, and useful.

19. Could the framework be extended to non-human suffering?

The intensity-over-time structure may be relevant to animal-welfare research, but the present USU calibration and WSI programme are human-centered.

Any non-human application would require species-specific behavioral and physiological evidence, animal-welfare expertise, and separate validation. Human and non-human estimates would not be combined by default.

20. How can researchers and organizations contribute?

WSI welcomes collaboration on data sourcing, domain expertise, state mapping, uncertainty modeling, software, replication, visualization, and independent review.

Researchers can also apply USU to their own data, propose alternative mappings, scrutinize future WSI methods, and publish critiques or extensions.

Help build a reliable global evidence resource

WSI is an independently developed research initiative. It is currently independent of government, corporate, and political funding; future support and conflicts of interest will be disclosed.

Collaboration is especially welcome from specialists in disease surveillance, humanitarian data, measurement science, uncertainty modeling, reproducible research, and data visualization.