Publications (Click on drop down menus for abstracts)

Singh, M. (2021). Heuristics in the delivery room. Science, 374(6565), 324-329. [LINK]

Press: Choiceology (podcast), Random Acts of Medicine (book), New York Times Upshot, Freakonomics MD, Tradeoffs Newsletter, LA Times, The Conversation, Quartz, Reuters Health, and 41 others 


Clinical decisions made in the delivery setting are often made under high pressure, great uncertainty, and have serious consequences for mother and baby. Theories of decision-making suggest that individuals in such settings may resort to using “heuristics”, or simplified decision-rules, to aid complex decision-making. This study investigates whether physicians’ delivery-mode decisions (i.e., when to perform a vaginal vs. a cesarean) are influenced by such a heuristic. Electronic health record data spanning 86,000 deliveries suggests that, if the prior patient had complications in one delivery-mode, the physician will be more likely to switch to the other -- and likely inappropriate -- delivery-mode on the subsequent patient, regardless of patient indication. There is evidence that this heuristic has small, suboptimal effects on patient health.

Results as a limerick

A patient has a bad reaction,

To the Doc’s deep dissatisfaction, 

Feeling unfit,

Doc cries out, "Oh sh*t!"

And switches her medical plan of action.

How Power Shapes Behaviors: Evidence from Physicians (with Stephen Schwab) (Forthcoming in Science)

Press: Tradeoffs Newsletter, Random Acts of Medicine (blog)


Power – the asymmetric control of valued resources — affects most human interactions. Though power is challenging to study using real-world data, a unique dataset lets us do so within the critical context of doctor-patient relationships. Using 1.5 million quasi-random assignments in US military emergency departments, we examine how power differentials between doctor and patient (measured using differences in military ranks) affect physician behavior. We find that power confers nontrivial advantages: “high-power” patients (who outrank their physician) receive more resources and have better outcomes than equivalently-ranked “low-power” patients. Patient promotions even increase physician effort. Furthermore, low-power patients suffer if their physician concurrently cares for a high-power patient. Doctor-patient concordance on race and sex also matters. Overall, power-driven variation in behavior can harm the most vulnerable in healthcare.

Results as a limerick

Is power too beckoning a call?

Since doctors are human after all,

We took the military's example,

Rank predicted care in our sample,

The mighty were heeded o'er the small.

Do Physicians Improve More from Positive or Negative Feedback? (with Jacob Zureich) (Forthcoming in Management Science)


We use clinical data on over 240,000 surgeries and quasi-experimental methods to examine how physicians respond to the surprise release of a performance "report card". Such feedback interventions are commonly used to encourage physicians to improve performance, yet show limited evidence of success. Our results show that these limited effects mask heterogeneous behavioral responses to feedback valence. In particular, physicians improve more from positive feedback than from negative feedback, with negative feedback even reducing performance for a non-trivial share of patients. Experiments with laypersons replicate these results and show that struggles with negative feedback can be mitigated by giving incentives directly tied to improvement and by adding qualitative information that helps individuals interpret past performance. These results are consistent with behavioral models that suggest cognitive and emotional difficulties limit how well individuals use negative feedback. Thus, feedback interventions in healthcare should be carefully designed to mitigate these counterproductive behavioral responses.

Results as a limerick

Are report cards a fad?

Or could they help just a tad?

We find feedback is tricky,

‘cuz priors are sticky

And the good helps more than the bad.

Working Papers

Rationing by Race (with Atheendar Venkataramani) [NBER WP LINK]

Press: Tradeoffs Newsletter


Discrimination may lead to rationing on the basis of group identity when resources become more scarce. We provide evidence of consequential rationing on the basis of an individual's race in a high-stakes setting: health care. Using detailed, time-stamped data on over 107,000 patient admissions from a large health system in the U.S., we find that in-hospital mortality increased for Black, but not White, patients as hospitals reached capacity, a state where biases in care provision are likely to emerge or be exacerbated. We identify rationing by wait times as a mechanism, also documenting that sick Black patients wait longer for care than healthy White patients, regardless of capacity levels. Applying text analysis techniques to clinical documentation, we provide suggestive evidence of disparities in provider effort as another mechanism.

Results as a limerick

On clinical capacity does care depend 

whether or not providers intend, 

Hospitals get busy,

all systems a-tizzy,

with disparities emerging in the end.