Table 5

Comparison of proportions of anonymous specimens before and after the intervention

Before interventionAfter intervention
Total kits (n)257 130175 947
Anonymous kits (n)2987840
Anonymous kits per 1 000 kits (95% CI)11.6 (11.2 to 12.0)4.8 (4.5 to 5.1)
Prevalence ratio (95% CI)Reference0.41 (0.38 to 0.44)
Prevalence difference per 1000 kits (95% CI)Reference−6.8 (−6.3 to −7.4)