Table 1 Comparison of previous estimates and reported levels of adherence, completeness, and correctness of the THAR with national joint replacement registries. THA: Total hip arthroplasty; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index

THAR

Primary THA

97.91%

(n = 1100)

78.55%

99.54%

Revision THA

81.48%

(n = 54)

n/a

93.18%

New Zealand Joint Registry [12]

Primary THA

96.3% (n = 28,970)

n/a

n/a

Revision THA

92.5% (n = 4263)

n/a

n/a

UK National Joint Registry [1]

Revision THA

79.6% (n = 9411)

n/a

n/a

Norwegian Arthroplasty Register [2]

Primary THA

99.6% (n = 85,082)

n/a

n/a

Revision THA

97.8% (n = 14,359)

n/a

n/a

Finnish Arthroplasty Registry [15]

Primary THA

96.1% (n = 2820)

n/a

n/a