type="main" xml:id="irel12127-abs-0001">
Employer-provided health
insurance may restrict job mobility, resulting in “job lock.” Previous
research on job lock finds mixed results using several methodologies. We
take a new approach to examine job lock by exploiting the discontinuity
created at age 65 through the qualification for Medicare. Using a novel
procedure for identifying age in months from matched monthly Current
Population Survey data and a relatively unexplored administration measure
of job mobility, we compare job mobility among male workers in the months
just prior to turning age 65 to job mobility in the months just after
turning age 65. We find no evidence that job mobility increases at the age
65 threshold when Medicare eligibility starts. We also do not find
evidence that other factors such as retirement, reduction in hours worked,
Social Security eligibility, pension eligibility, and sample changes
confound the results on job mobility in the month individuals turn 65.