RT Journal T1 INcidence and future expectancy of mental disease JF Journal of the American Medical Association JO Journal of the American Medical Association YR 1939 FD January 14 VO 112 IS 2 SP 146 OP 147 DO 10.1001/jama.1939.02800020052014 UL http://dx.doi.org/10.1001/jama.1939.02800020052014 AB Not only the present incidence of mental disease is a problem of major proportions but also that occasioned by the future expectancy of this condition. Modern civilization has led to an increasing urbanization of the population. The belief is prevalent that there has been an alarming increase in mental disease in recent years and that this increase is in a measure attributable to the stress and strain of urban environment.Dorn1 points out that the problem of measurement of the incidence of mental disease is complex, since there is no sharp line of demarcation between normality and abnormality. Even though there is a definite physical basis for many mental disorders, mental disease is fundamentally a cultural concept which varies with different groups. Many persons who might merely be considered eccentric in a rural district would be unable to cope with the exigencies of an urban environment and might even