1144 Table 2; cases are from the current reassessment, and populations from the 1981 Census of Population and Housing of the Australian Bureau of Statistics. Both crude rates and rates age-adjusted per 100,000 to the 1960 US population are presented. NSW at 42 crude and 32 adjusted was higher than those in other states but there was no signiﬁcant gradient. Similar data for MS for all Australians are NSW 36 crude and 35 adjusted, QLD 18 both crude and adjusted, SA 29 crude and 26 adjusted and WA 24 crude and 25 adjusted (data not presented). The prevalence rates are signiﬁcantly the highest for NSW and lowest for QLD for both crude and adjusted rates. There is a highly signiﬁcant gradient for the prevalence rates with NSW [ SA [ WA [ QLD. Exploring this gradient will be the topic of a later paper. J Neurol (2011) 258:1140–1149 General features of MS in two groups of UKI immigrants As noted in Methods, deﬁning the population at risk for age at immigration required that both numerator and denomi- nator be limited to the immigrants who entered Australia in 1947 or later. The total of 302 (207 female) MS cases in migrants from UKI into the four states were therefore divided into Group I for the earlier cases, the 44 (25 female) who had migrated before 1947, and Group II for the late or post-World War II cases, the 258 (182 female) who entered in 1947 or after. For each set and state their main features are summarized as mean values (Table 3). Within each group there were no signiﬁcant differences among the states in any of these factors. As expected, years Table 3 Characteristics of MS in UKI immigrants among the 44 Group I (early immigrant) cases who entered before 1947, and the 258 Group II (late or post-war immigrant) cases who entered in or after 1947, by state of residence in the Four States of Australia QLD 10(5) 1927.7 16.9 1952.2 41.2 70.2 1910.8 24.3 41 (28) 1959.8 23.0 1969.2 32.4 43.7 1937.3 9.4 51 (33) 1953.5 21.8 1965.9 34.1 48.9 1933.3 12.3 SA 5 (3) 1925.6 7.8 1963.0 45.2 63.2 1917.8 37.4 39 (27) 1962.7 25.3 1970.9 35.4 45.4 1935.6 10.1 44 (30) 1958.5 23.3 1970.0 36.5 47.4 1933.6 13.2 WA 10(6) 1927.8 8.5 1955.4 36.3 61.4 1919.6 27.8 56 (41) 1961.2 26.3 1970.4 35.6 46.2 1934.8 9.1 66 (47) 1956.1 23.6 1968.1 35.7 48.5 1932.5 11.9 Total four states 44 (25) 1927.8 9.5 1957.7 39.4 62.6 1918.4 29.9 258 (182) 1962.3 23.4 1971.6 33.0 42.3 1938.7 9.6 302 (207) 1957.2 21.4 1969.6 33.9 45.3 1935.9 12.5 State NSW Feature I. Early immigrants (before 1947) N(F) 19 (11) YOI 1928.5 AAI 6.6 YOO 1960.5 AAO 38.6 Age 81 59.1 YOB 1921.9 D O–I 31.9 II. Post war immigrants (1947?) N(F) 122 (86) YOI 1963.4 AAI 21.6 YOO 1973.2 AAO 31.3 Age 81 39.2 YOB 1941.8 D O–I 9.7 Both N(F) 141 (97) YOI 1958.7 AAI 19.6 YOO 1971.5 AAO 32.3 Age 81 41.8 YOB 1939.2 D O–I 12.7 123 N Number of cases, F females. YOI year of immigration, AAI age at immigration, YOO year of onset, AAO age at onset, age 81 age in 1981, YOB year of birth, D O–I years between immigration and onset. All values are means