Office Visits Preventing Emergency Room Visits: Evidence from the Flint Water Switch

Emergency department visits are costly to our health care system and to patients in terms of time and emotional health. We use the Flint water crisis to test if an exogenous increase in office visits reduced preventable emergency room visits. In September, 2015, citizens in Flint became aware of increased lead levels in their drinking water, resulting from the switch from Lake Huron to the Flint River. Using Medicaid claims for 2013-2016, we find that following this information shock the share of enrollees with lead tests increase by 3.2 percentage points, and the share with any office visit increased by 1.1 percentage points (4.2%). This led to a reduction of 3.3 preventable, non-emergent, and primary care treatable emergency room visits per 1000 eligible children (5.4%), which suggests an elasticity of -1.3. However, total payments increased by $51 dollars per Medicaid recipient-month. So while office visits reduced inefficient ER visits, overall health care costs increased. Furthermore, this $51 per month corresponds to an additional $1.4 million per year, which is of the same order of magnitude as the entire projected savings from the water switch ($2.5 million per year). The results are potentially applicable to all cities with high lead levels (e.g., Providence, Philadelphia, Baltimore).