PFO closure also incurs a risk of persistent atrial fibrillation and device-related adverse events. Compared with alternatives, anticoagulation probably increases major bleeding.319 Each of these 6 trials had 1 methodological features with a high risk of bias identified, including lack of blinding of participants and personnel, lack of blinding of outcome assessments, incomplete outcome data, and selective reporting.318 324 See Tables LXXV through LXXVII in online Data Supplement 1. 6.3.1. Electrocardiographic Monitoring (Continued) COR LOE New, Revised, or Unchanged The effectiveness of routine echocardiography to guide treatment selection for prevention of recurrent stroke is uncertain. (See knowledge byte following 6.3.2, recommendation 1.) IIb B-NR New recommendation. 6.4. Glucose COR LOE New, Revised, or Unchanged After AIS, it is reasonable to screen all patients for diabetes mellitus with testing of fasting plasma glucose, hemoglobin A1c , or an oral glucose tolerance test. Choice of test and timing should be guided by clinical judgment and recognition that acute illness may temporarily perturb measures of plasma glucose. In general, hemoglobin A1c may be more accurate than other screening tests in the immediate postevent period. IIa C-EO Recommendation wording modified from 2014 Secondary Prevention to match COR IIa stratifications and reworded for clarity. COR unchanged. LOE amended to conform with ACC/AHA 2015 Recommendation Classification System. See Table XCV in online Data Supplement 1 for original wording. 6.5. Other Tests for Secondary Prevention 6.5. Other Tests for Secondary Prevention COR LOE New, Revised, or Unchanged The usefulness of screening for thrombophilic states in patients with ischemic stroke is unknown. IIb C-LD Recommendation reworded for clarity from 2014 Secondary Prevention. COR unchanged. LOE amended to conform with ACC/AHA 2015 Recommendation Classification System. See Table XCV in online Data Supplement 1 for original wording. 