Regulators strengthened banking supervision in the aftermath of the Great Financial Crisis by stress testing banks intending to increase the amount of information available about the risks they face, improving their transparency and restoring market confidence. This study examines whether the results of stress tests conducted between 2009 and 2019 in the US and the EU have reduced the opacity of information about banks' credit risk. We study changes in banking sector opacity around the disclosure of stress test results in a panel data framework. We measure opacity by discrepancies in bank credit ratings issued by different agencies. The findings indicate a lower opacity level after disclosing the US test results. The most significant reduction occurs for systemic banks with higher leverage that fail the test. The European testing programme has specific disclosure features that could justify that the effect of disclosure of stress test results is more attenuated for EU banks. Some indirect evidence suggests that differences in stress test programmes and banking sector structure between the two regions may explain the result.

金融危机后，监管机构通过对银行进行压力测试来加强银行监管，旨在增加有关其所面临风险的信息量，提高透明度并恢复市场信心。本研究考察了美国和欧盟2009年至2019年间进行的压力测试结果是否降低了银行信用风险信息的不透明度。我们研究了银行业在面板数据框架中披露压力测试结果的不透明度变化。我们通过不同机构发布的银行信用评级的差异来衡量不透明度。研究结果表明，美国测试结果公布后，不透明度水平较低。最显着的减少发生在未通过测​​试、杠杆率较高的系统性银行。欧洲测试计划具有特定的披露特征，可以证明压力测试结果披露对欧盟银行的影响更为减弱。一些间接证据表明，两个地区之间压力测试计划和银行业结构的差异可能可以解释这一结果。