Does chiropractic utilization substitute for less available medical services?

In Muscatine, Iowa, a medically underserved rural area, a cohort study of health care utilization was made before and after a significant increase in medical manpower. There was a slight increase, rather than a decrease, in the use of chiropractic services associated with the growth in the physician manpower pool. The level of access to physician services was not a significant predictor of chiropractice utilization.