English classified his cases into three series—each 100 in number—according to the severity of the lesion.
Series 1. Fracture cases.
Series 2. Cases of concussion, contusion, and laceration.
Series 3. Miscellaneous cases.
The remote results as observed in the first and second series were as follows:—
| Series 1. | No effects | 31 |
| Slight effects | 50 | |
| Marked effects | 19 | |
| Series 2. | No effects | 48 |
| Slight effects | 42 | |
| Marked effects | 10 |
In the 200 cases, therefore, that come under Series 1 and 2, 79 experienced no ill effects from the injury, 92 developed slight effects, and definite defects were present in 29 cases.
Before alluding further to the mental and bodily condition of the patients subsequent to the accident, including their wage-earning capacity, it is necessary to enlarge on the fact that the depreciation in mental and physical faculties depends, not only on the severity of the injury, but also on the age, disposition, and status of the patient.
The effect of age.
All evidence tends to prove that head-injuries in the young and the old are more serious than when the accident occurs during middle life. In the old, the power of repair is impaired; in the young, the developing faculties are impeded in their progress.