Although during the past decade preventive measures have almost eliminated severe rickets, milder forms of this dyscrasia still persist. The desire to ascertain how prevalent rickets continues to be and, if possible, what its relationship is to climatic and certain other factors prompted the present fact-finding, cross-sectional survey. For this study two localities were chosen which differed markedly as to climate, one being in the cloudy northwestern part of the Pacific coast and the other in its sunny southwestern part, yet were of the same country and of the same altitude (sea level) and had inhabitants of similar habits of living and diet.
Portland had an average of 2,194 hours of sunshine per year, compared with 3,024 hours in San Diego—a difference of 38 per cent. In addition, for the years from 1930 to 1934 inclusive, the average annual temperature in Portland was 54.6 F., while that of San Diego
MOORE CU, BRODIE JL, THORNTON AJ, LESEM AM, CORDUA OB. FAILURE OF ABUNDANT SUNSHINE TO PROTECT AGAINST RICKETS. Am J Dis Child. 1937;54(6):1227-1238. doi:10.1001/archpedi.1937.01980060019002