A total of 113 articles were included.
Seven RCTs (6181 athletes), 2 prospective cohort studies (3558 athletes) and one retrospective cohort study (297 athletes) were included in the assessment of effectiveness.
The number of sprains in individual studies ranged from 8 to 224).
Shoes and taping (three RCTs and one prospective cohort).
One RCT (validity score 68) found high-tops with inflatable cuffs to be associated with a non-significant trend towards fewer sprains than low-tops or high-tops alone in basketball players (2.26 vs 4.06 vs 4.8 all 10 to the power to -4/player minute).
One RCT (validity score 23) found J-taped Flex was associated with fewer sprains than taping or untapped in basketball players (6.9 vs 14.7 vs 32.8/1000 participant games).
One RCT (validity score 40) found similar sprain rates for taped and cloth strapped ankles in football players (4 injuries over 1270 practice days vs 4 injuries over 1323 practice days).
One cohort study (validity score 11) found swivel shoes to be more effective in preventing sprains than soccer shoes, heel plates or cleats in football players (3% vs 5.6% vs 7.7% vs 8.5%).
Bracing (three RCTs and one retrospective cohort).
One RCT (validity score 60) found Air-Stirrup was associated with significantly fewer sprains than no intervention in basketball teams (1.6 vs 5.2 sprains/1000 athletes exposures.
One RCT (validity score 39) found Air-stirrup was associated with fewer sprains than no prevention in basketball players with a past history of ankle sprain (0.46 vs 1.16/1000 player hours) but no difference between groups in players without previous ankle injury (0.97 vs 0.92/ 1000 player hours).
One RCT (validity score 31) found that soccer players who used a cloth orthosis or those in an ankle disk training programme experienced significantly fewer sprains than the controls (3% vs 5% vs 17%).
One retrospective cohort (validity score 48) found orthosis to be more effective than taping in reducing sprains in football players (2.6 vs 4.9/1000 participant games).
Training (one RCT and one prospective cohort).
One RCT (validity score 45) found intensive sustained conditioning reduced sprain rates in soccer teams (2 vs 11 sprains).
One prospective cohort (validity score 32) reported a decrease in the incidence of sprains over years 1, 2, and 3 of an injury prevention programme for volleyball players (year 1: 0.9, year 2: 0.8, year 3: 0.5/1000 player hours.
Validity score: RCTs scored from 23 to 68 points and cohort studies scored from 11 to 48 points. Methodological flaws included: failure to report methods of randomisation and degree of blinding; lack of attention to possible confounding factors; information and selection bias; lack of attention to statistical methods; and failure to assess the effect of multiple interventions.