Research overview

Our approach

The pursuit of happiness as the goal of life is a very old idea, but it’s only in recent decades that academics have developed valid and reliable ways to measure wellbeing through self-reports.

Now, for the first time in human history, we can work out the best ways to improve global happiness in a scientifically rigorous way. But what are they? That is what the Happier Lives Institute was set up to find out.

We conduct foundational research on the nature and measurement of wellbeing and applied research where we synthesise the existing data on subjective wellbeing to discover what will have the biggest impact.  Our research draws on and develops previous work in the fields of philosophy, economics, and psychology.

To identify where additional resources can do the most good, we follow a three-stage process:

  1. Explore neglected global problems
  2. Identify cost-effective interventions for alleviating those problems
  3. Evaluate the best organisations that deliver those interventions

By focusing on happiness, we can compare these interventions and charities on a universal metric called wellbeing-adjusted life years (WELLBYs). One WELLBY is equivalent to a 1-point increase on a 0-10 life satisfaction scale for one year. Unlike measures of health or wealth, WELLBYs capture the overall benefit people receive from an intervention, which allows us to make apples-to-apples comparisons between interventions that impact different outcomes. 

The WELLBY approach is based on decades of research in social science, but we are the first to use this scientifically reliable tool to work out the best ways to help others.

What have we found so far?

Our search for funding opportunities starts with the expectation that money goes furthest in low-income countries. So far, we’ve evaluated four promising interventions in terms of happiness: ​cash transfers, psychotherapy, deworming pills, and antimalarial bednets.

We review our research on these interventions in detail below, but donors can find a brief overview of our top charity recommendations here.

Cash transfers

A large number of academic studies show that cash transfers are a very effective way to reduce poverty. The strength of this evidence led GiveWell (a charity evaluator) to recommend GiveDirectly as one of their top charities. But what impact do cash transfers have on subjective wellbeing? We conducted a systematic review and meta-analysis of 45 studies which found that cash transfers have a small, long-lasting and statistically significant positive effect on subjective wellbeing and mental health. This work was published in Nature Human Behaviour in 2022.


However, we suspected that treating people with depression in low-income countries could be even more cost-effective than cash. After a rigorous assessment of 76 mental health programmes, we identified StrongMinds as one of the best charities delivering psychotherapy in a low-income setting.

Then, drawing on evidence from over 80 studies and over 140,000 participants, we made a direct comparison of StrongMinds and Give Directly based on their effects on subjective wellbeing and mental health. We found that StrongMinds’ eight-week psychotherapy course has a similar effect to a $1,000 dollar cash transfer but it costs much less to provide, only $170 per person. To our knowledge, this is the first time that the cost-effectiveness of two different types of intervention has been compared in terms of subjective wellbeing. We also conducted additional analysis to estimate the spillover effects of cash transfers and psychotherapy on other household members. 

Bringing together this whole body of research, we estimate that StrongMinds is 7.5 times more cost-effective than GiveDirectly.

This finding presents a challenge to current thinking about the best ways to improve the lives of others and suggests that treating mental health conditions should be a much higher priority for philanthropists and policymakers.  

Note and future update to our analysis

Our current estimation for StrongMinds is that a donation of $1,000 produces 62 WELLBYs (or 7.5 times GiveDirectly cash transfers). See our changelog.

However, we have been working on an update to our analysis since July 2023 and expect to be ready by the end of 2023. This will include using new data and improving our methods. We expect our cost-effectiveness estimate will decrease by about 25% or more – although this is a prediction we are very uncertain about as the analysis is yet to be done.

While we expect the cost-effectiveness of StrongMinds will decrease, we think it is unlikely that the cost-effectiveness will be lower than GiveDirectly. Donors may want to wait to make funding decisions until the updated report is finished.


From 2011 until 2022, GiveWell recommended several deworming charities that treat large numbers of children for intestinal worms. The case for deworming is that it is very cheap (less than $1 per year of treatment per person) and there is suggestive evidence it might have large effects on later income (by improving educational outcomes which enable recipients to earn more in later life). 

GiveWell has claimed that deworming programmes are several times more cost-effective than cash transfers. But how does deworming compare to treating depression, particularly when we look for the effects on happiness instead of income?

The evidence of the long-term impacts of deworming comes primarily from one study, the Kenyan Life Panel Survey. Using this large data set, we conducted the first analysis of the impact of deworming on subjective wellbeing that we know of (report forthcoming). 

We find a very small, but statistically non-significant effect of deworming on happiness. Even if we take this non-significant effect at face value, deworming still looks about half as cost-effective as StrongMinds, with wide uncertainty.

Because the effect is so small and uncertain, and because the data come from a single study, we do not recommend any deworming charities over StrongMinds at this time.

Antimalarial bednets

The insecticide-treated nets distributed by the Against Malaria Foundation (AMF) have been considered a safe bet by the effective altruism community for many years: nets cost around $2 each and it costs, on average, a few thousand dollars to save a life. But how do we compare the relative value of interventions that improve lives against those that extend lives? Our report, The Elephant in the Bednet, explores this topic in detail. 

As the title suggests, this is a question that people (understandably) find discomforting, but the issue is important and unavoidable. The relative value of extending or improving life depends very heavily on your philosophical views about the badness of death and the point at which a person’s wellbeing changes from positive to negative. Although these issues are well-known in academic philosophy, they are almost entirely glossed over by charity evaluators. 

Using existing estimates, we examined how the cost-effectiveness of AMF changes under various philosophical views. We find that the cost-effectiveness changes dramatically as we shift from one extreme of (reasonable) opinion to the other. At one end, AMF is 1.6x better than StrongMinds. At the other, StrongMinds is 10x better than AMF. Ultimately, AMF is less cost-effective than StrongMinds under almost all assumptions. 

Because StrongMinds is more cost-effective under more views, and because the cost-effectiveness is potentially greater, our general recommendation to donors is StrongMinds. However, we recognise that some donors will hold views that lead them to conclude that AMF does more good, and we advise interested individuals to read the full report to inform their decision-making.


We show the cost-effectiveness of the interventions we have evaluated so far in the graph below. The graph shows our estimate of how many WELLBYs would be generated from a $1,000 donation.


Notes for reading the graph...

  • The diamonds represent the central estimate of cost-effectiveness.
  • The solid whiskers represent the 95% confidence intervals for StrongMinds, Deworm the World, and GiveDirectly.
    • Arrows on the end of the whiskers represent that the uncertainty extends beyond the limits of the x axis.
  • The vertical dashed line represents 0 WELLBYs.
  • The vertical dotted line is the point estimate of StrongMinds’ cost-effectiveness.
  • The lines for AMF (the Against Malaria Foundation) are different from the others. They represent the upper and lower bound of cost-effectiveness for different philosophical views (not 95% confidence intervals). Think of them as representing moral uncertainty, rather than empirical uncertainty. The upper bound represents the assumptions most generous to extending lives and the lower bound represents those most generous to improving lives.
  • The slogan version of the philosophical views are: 
    • Deprivationism: prioritise the youngest
    • Time-relative interest account (TRIA): prioritise older children over infants. 
    • Epicureanism: prioritise living well, not living long

Foundational research

In addition to our empirical research, we’ve also investigated a number of philosophical questions about the nature and measurement of wellbeing, including:

What’s next?

So far, we’ve looked at four well-evidence interventions in terms of their impact on subjective wellbeing. Our findings have revealed surprising results and suggest new priorities for doing the most good. However, it’s highly unlikely that we’ve found the best ways to improve happiness already. 

We have a pipeline of promising charities and interventions to analyse next year:

Charities we want to evaluate:

Interventions we want to evaluate:

  • Reducing air pollution 
  • Preventing childhood trauma 
  • Mental health apps 
  • Cataract surgery 
  • Fistula repair surgery

We have a long list of charities and interventions that we won’t get to in 2023 but plan to examine in future years. Eventually, we plan to consider systemic interventions and policy reforms that could affect the wellbeing of larger populations at all income levels.

Funders of different sizes have different priorities so we’ll continue to investigate where to spend the next dollar as well as developing a diversified portfolio of funding opportunities with varying levels of uncertainty.