Suicide is a very poor indicator of the dead/neutral point, for a host of reasons.

A few small, preliminary surveys I've seen place it around 2/10, though it ranges from about 0.5 to 6 depending on whom and how you ask.

(I share your concerns in parentheses, and am doing some work along these lines - it's been sidelined in part due to covid projects.)

Hah! I was working on them before getting sidelined with covid stuff.

I can send you the drafts if you send me a PM. The content is >80% done (I've decided to add more, so the % complete has dropped) but they need reorganising into ~10 manageable posts rather than 3 massive ones.

Thanks Aidan! Hope you're feeling better now.

Most of your comments sound about right.

On retention rates: Your general methods seem to make sense, since one would expect gradual tapering off of benefits, but your inputs seem even more optimistic than I originally thought.

I'm not sure Strong Minds is a great benchmark for retention rates, partly because of the stark differences in context (rural Uganda vs UK cities), and partly because IIRC there were a number of issues with SM's study, e.g. a non-randomised allocation and evidence of social desirability bias in outcome measurement, plus of course general concerns related to the fact it was a non-peer-reviewed self-evaluation. Perhaps retention rates of effects from UK psychotherapy courses of similar duration/intensity would be more relevant? But I haven't looked at the SM study for about a year, and I haven't looked into other potential benchmarks, so perhaps yours was a sensible choice.

Also not a great benchmark in a UK context, but Haushofer and colleagues recently did a study* of Problem Management+ in Uganda that found no benefits at the end of a year (paper forthcoming), even though it showed effectiveness at the 3 month mark in a previous study in Kenya.

*Haushofer, J., Mudida, R., & Shapiro, J. (2019). The Comparative Impact of Cash Transfers and Psychotherapy on Psychological and Economic Well-being. Working Paper. Available upon request.

Do you think GiveWell top charities are the best of all current giving opportunities? If so, what is the next best opportunity?

Do you think adopting subjective wellbeing as your primary focus would materially affect your recommendations?

In particular:

(a) Would using SWB as the primary outcome measure in your cost-effectiveness analysis change the rank ordering of your current top charities in terms of estimated cost-effectiveness?

(b) If it did, would that affect the ranking of your recommendations?

(c) Would it likely cause any of your current top charities to no longer be recommended?

(d) Would it likely cause the introduction of other charities (such as ones focused on mental health) into your top charity list?

How likely is it that GiveWell will ultimately (e.g. over a 100-year or 10,000-year period) do more harm than good? If that happens, what is the most likely explanation?

A recent post on this forum (one of the most upvoted of all time) argued that "randomista" development projects like GiveWell's top charities are probably less cost-effective than projects to promote economic growth. Do you have any thoughts on this?

I like your general approach to this evaluation, especially:

• the use of formal Bayesian updating from a prior derived in part from evidence for related programmes
• transparent manual discounting of the effect size based on particular concerns about the direct study
• acknowledgement of most of the important limitations of your analysis and of the RCT on which it was based
• careful consideration of factors beyond the cost-effectiveness estimate.

I'd like to see more of this kind of medium-depth evaluation in EA.

I don't have time at the moment for a close look at the CEA, but aside from limitations acknowledged in your text, 3 aspects stand out as potential concerns:

1. The "conservative" and "optimistic" results are quite extreme. This seems to be in part because "conservative" and "optimistic" values for several parameters are multiplied together (e.g. DALYs gained, yearly retention rate of benefits, % completing the course, discount rates...). As you'll know, it is highly improbable that even, say, three independent parameters would simultaneously obtain at, say, the 10th percentile: 0.1*0.1*0.1 = 0.001. Did you consider making a probabilistic model in Guesstimate, Causal, Excel (with macros for Monte Carlo simulation), R, etc in order to generate confidence intervals around the final results? (I appreciate there are major advantages to using Sheets, but it should be fairly straightforward to reproduce at least the "Main CEA" and "Subjective CEA inputs" tabs in, for example, Guesstimate. This would also enable a rudimentary sensitivity analysis.)

2. The inputs for "Yearly retention rate of benefits" (row 10) seem pretty high (0.30, 0.50, and 0.73 for conservative, best guess, and optimistic, respectively) and the results seem fairly sensitive to this parameter. IIRC the study this was based on only had an 8-week follow-up, which would be about half your "conservative" figure (8/52 = 0.15). Even their "extended" follow-up (without a control group) was only for another 2 months. It is certainly plausible that the benefits endure for several months, but I would say that estimates of about 0.1, 0.3, and 0.7 are more reasonable. With those inputs, the cost per DALY increases to about $47,000, $4,500, or $196. That central figure is roughly on a par with CBT for depression in high-income countries, i.e. pretty good but not comparable with developing-country interventions. (And I wouldn't take the "optimistic" figure seriously for the reasons given in (1) above.)

3. I haven't seen the "growth model" on which the cost estimates are based, but my guess is that it doesn't account for the opportunity cost of facilitators' (or participants') time. IIRC each course is led by two "skilled" volunteers who may otherwise do another pro-social activity.

There is also evidence that health problems have a much smaller effect on subjective well-being than one might imagine.

This is only the case for (some) physical health problems, especially those associated with reduced mobility. People tend to underestimate the SWB impact of (at least some) mental health problems. See e.g. Gilbert & Wilson, 2000; De Wit et al., 2000; Dolan & Kahneman, 2007; Dolan 2008; Pyne et al., 2009; Karimi et al., 2017

You might want to mention the publication date (1937)