Table 1

Boxing exposure from 1900 to 2002

Boxing era	Reference	Estimated era of fighters	N	Career length and boxing history	Average career length (years)	Average no of bouts	Range
NA, Data not available.
1900–1955	Spillane¹⁵	1900–1930s	5	15–22 years; professional	22.2	287.5	200–350
	Mawdsley & Ferguson¹⁰	1915–1930s	10	12–36 years; booth and professional	14.3	227	100–600
	Corsellis et al¹⁶	1900–1940	15	11–35 years; amateur and professional	20.7	495	300–700+
	Roberts³	1929–1955	224	3–10+ years; professional	NA	NA	<50– 150+
1950–1995	Ross et al¹⁷	1950s–1970s	27	Unknown; professional	NA	27.5	1–100
	Casson et al¹⁸	1950–1970	18	1–22 years; professional	9.6	29	1–128
	Drew et al¹⁹	1980s	19	Unknown; professional	NA	13.7	0–37
	Jordan et al²¹	1990–1995	42	4–20 years; professional	9.5	10	0–36
2000–	Ravdin et al²⁰	2002	18	Unknown; professional	5.3	15.4	1–56
2000–	Hogg⁹	2002	277	1–32 years; professional	4.7	11.2	1–138