When Does a Self-Assessment Carry Information? Regional Variation in the Corroboration of Reported Antimicrobial Resistance Surveillance Capacity Across 182 Countries

International antimicrobial resistance (AMR) monitoring relies on the unverified Tracking AMR Country Self-Assessment Survey (TrACSS). Whether its ratings provide equivalent information across settings remains unclear. This cross-sectional analysis examined correspondence between self-rated surveillance capacity and laboratory capabilities in the 2025 public dataset, by WHO region and income. For 182 countries answering surveillance item 3.5, a corroboration score (0–4) incorporated reference-laboratory susceptibility testing for 12 priority bacteria, standardized testing guidelines and external quality assurance beyond reference laboratories, and reporting a laboratory count. Associations were assessed using Spearman correlations. Mean corroboration increased from 1.50 at rating A to 3.43 at rating D (overall ρ = 0.43; 95% CI 0.29–0.55; p < 0.001). Regional correlations ranged from 0.67 in the Eastern Mediterranean to 0.20 in the Western Pacific; confidence intervals excluded zero in three regions but included zero in Europe and the Western Pacific. Mean corroboration did not differ significantly between regions (Kruskal–Wallis p = 0.80). Across six regions, correlation strength was inversely rank-ordered with corroboration among low self-raters (ρ = −1.00; exact p = 0.003), consistent with ceiling effects. Among 107 countries claiming standardized national surveillance, 68 (63.6%) reported action plans at best partially implemented. Laboratory-count non-reporting increased with income, from 7.4% to 27.8% (trend p = 0.035). Self-ratings showed moderate overall correspondence with laboratory capabilities reported by the same respondents, with regional variation. These findings support reporting corroboration alongside ratings and caution against assuming equivalent measurement performance across settings; they do not constitute independent validation of national capacity.