UCL School of Management

Research seminar

Lesley Meng, Wharton


Thursday, 24 January 2019
15:00 – 16:30

UCL School of Management is delighted to welcome Lesley Meng, Wharton, to host a seminar discussing ‘The Impact of Medication Delays on Patient Health in the ICU: Estimating Marginal Effects Under Endogenous Delays’


We study the hospital intensive care unit (ICU) to investigate the causal impact of medication delays on patient health. The ICU is an ideal setting to empirically study this question since patients are often in critical condition and require medications to remain in healthy states (as measured by vital signs). Since observed medication delays are endogenous, we use unit-level factors such as shift changes, physician rounding, and care coordination activities to identify the exogenous portion of medication delays using an instrumental variable approach. Using patient vital sign data electronically archived every few minutes, merged with the electronic medical record and the medication order database, we can quantify the impact of these exogenous delays in medication on novel and granular measures of patient health constructed using patient vital signs. We find that medications are delayed by an average of 88 minutes in the ICU, and delays in certain groups of medications in this setting cause an increase in the odds that the patient will enter an unhealthy state following the delay. Most importantly, the magnitudes of these effects vary by medication type, which suggests that different groups of medications in this setting have heterogeneous delay costs. Our data-driven insights can assist healthcare providers working in a complex and fast-paced ICU to make better medication prioritization decisions during busy times (such as shift changes). This work generalizes to services where delays can lead to undesirable outcomes and the prioritization of attention is important due to limited resources; examples of this include emergency services such as firetrucks, ambulances, and project management, among others.

Open to
PhD Programme
Last updated Wednesday, 16 January 2019